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Silva Fennica 1926-1997
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1960-1969
Acta Forestalia Fennica
1953-1968
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1913-1932

Articles containing the keyword 'Pinus sylvestris'

Category : Article

article id 5635, category Article
Tommi Ruha, Martti Varmola. (1997). Precommercial thinning in naturally regenerated Scots pine stands in northern Finland. Silva Fennica vol. 31 no. 4 article id 5635. https://doi.org/10.14214/sf.a8537
Keywords: Pinus sylvestris; precommercial thinning; branch diameter; early development; external quality
Abstract | View details | Full text in PDF | Author Info

The effects of precommercial thinning on the quantity and external quality of young Scots pine (Pinus sylvestris L.) stands were examined over two 10-year periods in an experiment comprising five stands growing on sub-dry sites in Finnish Lapland, northern Finland. The thinning treatments applied resulted in stand densities of 625, 1111, 1600, 2500 and 4444 stems ha-1 and a no-treatment, unthinned plot with a randomised block lay-out of two or three replications in each stand. The dominant height of the stands varied between 4 and 8 m at the time of thinning.

The trees reacted only slightly to the increase in growing space during the first ten years following precommercial thinning. During the second 10-year period, increased growing space was reflected more clearly in diameter and volume increment. These reactions were more evident in stands thinned at an early stage. The increment of the thinnest 100–200 trees ha-1 in each treatment was poor. The results showed that when the main principle in precommercial thinning is to achieve even spacing, the remaining smallest trees fail to react positively to the increase in growing space. In other words, the target of precommercial thinning should be to concentrate the increment on the tallest trees, even though they are located in groups. The external quality of the trees in stands where precommercial thinning was carried out at a later stage was high, and the diameter of the thickest branch along the butt log remained under 20 mm. Branch diameter was greater in stands thinned at an early stage. The effect of precommercial thinning on branch diameter when comparing the extreme treatments averaged 5 mm. When the aim of stand management is to combine high quality and good yield in naturally regenerated Scots pine stands in northern Finland, precommercial thinning should not be carried out before the dominant height of 7–8 m. The intensity of precommercial thinning depends on the yield targets of the first commercial thinning. A spacing of 2,500 stems ha-1 satisfies the requirements of both high quality and adequate yield.

  • Ruha, E-mail: tr@mm.unknown (email)
  • Varmola, E-mail: mv@mm.unknown
article id 5634, category Article
Leena Finér, Mika Nieminen. (1997). Dry mass and the amounts of nutrients in understorey vegetation before and after fertilization on a drained pine bog. Silva Fennica vol. 31 no. 4 article id 5634. https://doi.org/10.14214/sf.a8536
Keywords: Pinus sylvestris; biomass; peatlands; ground vegetation; field layer; litter; root systems; bottom layer
Abstract | View details | Full text in PDF | Author Info

Dry mass and nutrient (N, P, K, Ca, Mg, B) contents of field layer vegetation and a combination of bottom layer vegetation and litter (referred to as bottom/litter layer in the text) were studied one year before and three years after fertilization (NPK and PK) on a drained low-shrub pine bog in eastern Finland. The results of an earlier study on the tree layer were combined with those of this study in order to estimate the changes caused by fertilization in the total plant biomass and litter. Before fertilization the average dry mass of the field and bottom/litter layers was 8,400 kg ha-1 and 7,650 kg ha-1, respectively. The above-ground parts accounted for 25% of the total field layer biomass. The dry mass of the field and bottom/litter layers together was < 20% of the dry mass accumulated in the total plant biomass and litter. The corresponding figures for N, P, K, Ca, Mg and B were 44%, 38%, 30%, 38%, 31% and 17%, respectively. Fertilization did not significantly affect the dry mass of either the field layer vegetation or the bottom/litter layer. 33% of the applied P was accumulated in the total plant biomass and litter on the PK-fertilized plots, and 25% on the NPK-fertilized plots. For the other elements, the proportions on the PK-fertilized plots were K 31%, Ca 6%, Mg 11% and B 13%. On the NPK-fertilized plots, the corresponding figures were N 62%, K 32%, Ca 6%, Mg 9% and B 13%. Except for B and K, the accumulation of fertilizer nutrients in the understorey vegetation and litter was of the same magnitude or greater than the uptake by the tree layer.

  • Finér, E-mail: lf@mm.unknown (email)
  • Nieminen, E-mail: mn@mm.unknown
article id 5632, category Article
Annikki Mäkelä, Veli-Pekka Ikonen, Petteri Vanninen. (1997). An application of process-based modelling to the development of branchiness in Scots pine. Silva Fennica vol. 31 no. 3 article id 5632. https://doi.org/10.14214/sf.a8534
Original keywords: puutavara; mänty; kasvu; hiili; läpimitta; biomassa; oksat; laatu; latvus; simulointi; kasvumallit; mallit; hiilitase; oksaisus
English keywords: Pinus sylvestris; carbon balance; simulation; pipe model; timber quality; growth model; branching; crown structure; whorl
Abstract | View details | Full text in PDF | Author Info

A process-oriented tree and stand growth model is extended to be applicable to the analysis of timber quality, and how it is influenced by silvicultural treatments. The tree-level model is based on the carbon balance and it incorporates the dynamics of five biomass variables as well as tree height, crown base, and breast height diameter. Allocation of carbon is based on the conservation of structural relationships, in particular, the pipe model. The pipe-model relationships are extended to the whorl level, but in order to avoid a 3-dimensional model of entire crown structure, the branch module is largely stochastic and aggregated. In model construction, a top-down hierarchy is used where at each step down, the upper level sets constraints for the lower level. Some advantages of this approach are model consistency and efficiency of calculations, but probably at the cost of reduced flexibility. The detailed structure related with the branching module is preliminary and will be improved when more data becomes available. Model parameters are identified for Scots pine (Pinus sylvestris L.) in Southern Finland, and example simulations are carried out to compare the development of quality characteristics in different stocking densities.

  • Mäkelä, E-mail: am@mm.unknown (email)
  • Ikonen, E-mail: vi@mm.unknown
  • Vanninen, E-mail: pv@mm.unknown
article id 5629, category Article
Risto Sievänen, Eero Nikinmaa, Jari Perttunen. (1997). Evaluation of importance of sapwood senescence on tree growth using the model Lignum. Silva Fennica vol. 31 no. 3 article id 5629. https://doi.org/10.14214/sf.a8531
Keywords: Pinus sylvestris; growth; growth model; pipe-model theory; sapwood senescence; open-grown trees
Abstract | View details | Full text in PDF | Author Info

The effects of two alternative formulations of sapwood senescence on the behaviour of model LIGNUM (with parameter values adjusted for Scots pine (Pinus sylvestris L.) growing southern Finland) were studied. The two alternatives were autonomous sapwood senescence assuming a maximum age for the tree ring, and sapwood senescence that is controlled by the mortality of foliage. For the latter alternative two hypothetical further mechanisms were stipulated. All the formulations were implemented in LIGNUM. Simulations were made with all model variants for fertile and poor soil conditions using high, normal and low rates of foliage mortality. The simulation results were compared against of a data set consisting of 11 open grown Scots pine trees from southern Finland. Observations of heartwood proportion were used in this study. They show that heartwood starts to increase in trees from age of approximately 20 years onwards. The simulation results showed no differences between fertile and poor soil conditions as regards heartwood formation. Of the variants of foliage-controlled sapwood senescence the one where death of sapwood in a tree segment induces sapwood senescence in the tree parts below only slightly was the best. This and the autonomous sapwood senescence corresponded equally well to the observations. In order to make more refined conclusions additional data and simulations are necessary.

  • Sievänen, E-mail: rs@mm.unknown (email)
  • Nikinmaa, E-mail: en@mm.unknown
  • Perttunen, E-mail: jp@mm.unknown
article id 5616, category Article
Hannu Hökkä, Virpi Alenius, Timo Penttilä. (1997). Individual-tree basal area growth models for Scots pine, pubescent birch and Norway spruce on drained peatlands in Finland. Silva Fennica vol. 31 no. 2 article id 5616. https://doi.org/10.14214/sf.a8517
Keywords: Pinus sylvestris; site quality; Picea abies; Betula pubescens; forest drainage; mixed models; peatlands; growth models
Abstract | View details | Full text in PDF | Author Info

Models for individual-tree basal area growth were constructed for Scots pine (Pinus sylvestris L.), pubescent birch (Betula pubescens Ehrh.) and Norway spruce (Picea abies (L.) Karst.) growing in drained peatland stands. The data consisted of two separate sets of permanent sample plots forming a large sample of drained peatland stands in Finland. The dependent variable in all models was the 5-year basal area growth of a tree. The independent tree-level variables were tree dbh, tree basal area, and the sum of the basal area of trees larger than the target tree. Independent stand-level variables were stand basal area, the diameter of the tree of median basal area, and temperature sum. Categorical variables describing the site quality, as well as the condition and age of drainage, were used. Differences in tree growth were used as criteria in reclassifying the a priori site types into new yield classes by tree species. All models were constructed as mixed linear models with a random stand effect. The models were tested against the modelling data and against independent data sets.

  • Hökkä, E-mail: hh@mm.unknown (email)
  • Alenius, E-mail: va@mm.unknown
  • Penttilä, E-mail: tp@mm.unknown
article id 5611, category Article
Arja Lilja, Timo Kurkela, Sakari Lilja, Risto Rikala.. (1997). Nursery practices and management of fungal diseases in forest nurseries in Finland. A review. Silva Fennica vol. 31 no. 1 article id 5611. https://doi.org/10.14214/sf.a8512
Keywords: Pinus sylvestris; Picea abies; forest nursery; Betula spp.; Finland; damping-off; grey mold; root dieback; scleroderris canker; pine twisting rust; seedlings; fungal diseases; Godronia multispora; Lophodermium needle cast; snow blights; birch rust; stem lesions of birch; leaf lesions of birch; Lophodermium pinastri; Botrytis cinerea; Melampsora pinitorqua; Melampsoridium betulinum
Abstract | View details | Full text in PDF | Author Info

The purpose of this article was to collate the literature on fungal diseases that occur on seedlings in forest nurseries. It describes the symptoms of the diseases, the infection pattern of each fungus and the possibilities of controlling the diseases. As background a short introduction is given on forests and nursery practices in Finland.

  • Lilja, E-mail: al@mm.unknown (email)
  • Kurkela, E-mail: tk@mm.unknown
  • Lilja, E-mail: sl@mm.unknown
  • Rikala., E-mail: rr@mm.unknown
article id 5609, category Article
Matti Maltamo. (1997). Comparing basal area diameter distributions estimated by tree species and for the entire growing stock in a mixed stand. Silva Fennica vol. 31 no. 1 article id 5609. https://doi.org/10.14214/sf.a8510
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; dbh distribution; parameter prediction; Weibull distributions
Abstract | View details | Full text in PDF | Author Info

The purpose of this study was to compare the Weibull distributions estimated for the entire growing stock of a stand and separately for Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) in describing the basal area diameter distributions in mixed stands. The material for this study was obtained by measuring 553 stands located in eastern Finland. The parameters of the Weibull distribution were estimated using the method of maximum likelihood. The models for these parameters were derived using regression analysis. Also, some parameter models from previous studies were compared with the measured distribution. The obtained distributions were compared using the diameter sums of the entire growing stock, diameter sums by tree species and of the sawtimber part of the growing stock. The results showed that far more accurate results were obtained when the distributions were formed using parameter models separately for the different tree species than when using parameter models for the entire growing stock. This was already true when considering the entire growing stock of the stand and especially when the results were examined by tree species. When the models for the entire growing stock were applied by tree species in relation to basal areas, the results obtained were overestimates for Norway spruce and underestimates for Scots pine. The models from earlier studies, where parameter models were estimated separately for tree species from the National Forest Inventory data, showed good fits also in regard to the data of this study.

  • Maltamo, E-mail: mm@mm.unknown (email)
article id 5608, category Article
Harri Mäkinen. (1997). Possibilities of competition indices to describe competitive differences between Scots pine families. Silva Fennica vol. 31 no. 1 article id 5608. https://doi.org/10.14214/sf.a8509
Keywords: Pinus sylvestris; Scots pine; tree breeding; stand density; tree improvement; competition indices
Abstract | View details | Full text in PDF | Author Info

Possibilities of distance-independent and -dependent competition indices to describe the competition stress of an individual tree was studied in Southern Finland. Five half-sib open-pollinated families and one check lot of Scots pine (Pinus sylvestris L.) was used as study material in order to analyse competitive interactions of crown form and stand density variation. Almost all competition indices correlated strongly with radial increment. Thus distance-independent indices were adequate to describe competition in young row plantations, where distance effects between trees were implicitly eliminated. Correlations between indices and height increment were not significant. Along with the increase in competition, the width and length of the crown and the diameter increment of the stem of some narrow-crowned families decreased slowly compared to wide-crowned families.

  • Mäkinen, E-mail: hm@mm.unknown (email)
article id 5605, category Article
Matti Haapanen, Marja-Leena Annala, Pirkko Velling. (1997). Progeny trial estimates of genetic parameters for growth and quality traits in Scots pine. Silva Fennica vol. 31 no. 1 article id 5605. https://doi.org/10.14214/sf.a8506
Keywords: Pinus sylvestris; Scots pine; wood quality; genetic correlation; heritability; progeny testing
Abstract | View details | Full text in PDF | Author Info

Estimates of individual heritability and genetic correlation are presented for a set of 10 growth and quality traits based on data from 16 Scots pine (Pinus sylvestris L.) progeny trials in Finland. Seven of the traits (tree height, stem diameter, crown width, Pilodyn value, branch diameter, branch angle and branch number) were objectively measured, whereas three traits (stem straightness, branching score and overall score) were assessed visually. The genetic correlations were mostly moderate or low, and favourable from the tree breeder's point of view. All variables related to tree size correlated relatively strongly and positively. Tree height exhibited a more favourable genetic relationship with the crown form traits than diameter, the latter showing positive correlation with branch diameter. Except for the slight negative correlation between branch angle and branch diameter, the branching traits were not notably correlated. The pilodyn value was positively correlated with stem diameter, reflecting negative correlation between diameter growth and wood density. The highest genetic correlations occurred among the two visually evaluated quality scores and branch diameter. All of the heritabilities were less than 0.4. Overall score, Pilodyn, branch angle, branching score and tree height showed the highest heritability.

  • Haapanen, E-mail: mh@mm.unknown (email)
  • Annala, E-mail: ma@mm.unknown
  • Velling, E-mail: pv@mm.unknown
article id 5565, category Article
Tytti Sarjala, Seppo Kaunisto. (1996). Effect of different potassium sources on the seasonal variation of potassium and free polyamines in Scots pine needles. Silva Fennica vol. 30 no. 4 article id 5565. https://doi.org/10.14214/sf.a8500
Keywords: Pinus sylvestris; needles; putrescine; potassium deficiency; seasonal fluctuation; spermidine; spermine
Abstract | View details | Full text in PDF | Author Info

Seasonal fluctuations in free polyamines, spermidine, spermine, putrescine and potassium concentrations were studied for two years (1992–1993) in three needle years of Scots pine (Pinus sylvestris L.) grown on a drained mire in western Finland. Seven different fertilizer treatments involving five different sources of potassium were used.

Putrescine concentrations were high in winter and in May but low in summer. High peaks in putrescine in March and May could be found in unrefertilized or rock phosphate treatments. Spermidine and spermine concentrations were high in March and May. In December spermine concentrations were low. Biotite increased the needle potassium concentrations less than the other potassium fertilizers but the putrescine concentrations or the putrescine/spermidine ratio to about the same level. This suggests that biotite, although very slowly soluble, can reasonably satisfy potassium nutrition of young pine trees.

The potassium concentrations of needles in all the fertilization treatments were higher in winter than in summer. The response of putrescine to the potassium concentration was strongly negative in all the needle years and sampling times. In March, May and December the response of putrescine to potassium was fairly similar in both years but not in June and August. The results suggest that the potassium concentrations during the growing season cannot be used for estimating the potassium nutrition of trees, because the variation between the years may be substantial, whereas the needle putrescine concentration or putrescine/spermidine ratio indicates the suboptimum potassium status of Scots pine fairly well. Needle putrescine concentrations over 500 nmol g-1FW quite regularly coincided with a unsatisfactory potassium nutrition and concentrations over 1,000 nmol g-1FW were a reliable indication of potassium deficiency. Putrescine/spermidine ratios below 5 indicated a satisfactory potassium nutrition in all needle years throughout the year.

  • Sarjala, E-mail: ts@mm.unknown (email)
  • Kaunisto, E-mail: sk@mm.unknown
article id 5599, category Article
Vadim V. Gorshkov, Irene J. Bakkal. (1996). Species richness and structure variations of Scots pine forest communities during the period from 5 to 210 years after fire. Silva Fennica vol. 30 no. 2–3 article id 5599. https://doi.org/10.14214/sf.a9244
Keywords: Pinus sylvestris; biodiversity; succession; Scots pine; forest ecology; Russian Federation; fire ecology; postfire recovery
Abstract | View details | Full text in PDF | Author Info

Postfire recovery of species diversity (including a number of species, entropy of species relative coverage (Shannon index of species diversity) was studied in lichen and green moss site types of Scots pine (Pinus sylvestris L.) forests in the central part of the Kola Peninsula. The results obtained indicate the difference in the dynamics of characteristics of biodiversity of forest components during postfire recovery. The stabilization of separate components of forest community varies in time from 5–15 to 120–140 years after the fire. Characteristics of the dwarf shrub and herb stratum recovered and stabilized 5–15 years after fire, while the complete stabilization of characteristics of moss-lichen cover is observed in community with fire ages of 90–140 years. Species richness of tree stratum recovered 120–140 years after fire. Time of complete stabilization of species richness of the community was estimated 120–140 years after fire. The size of the area over which characteristics of the biodiversity were estimated effected the mean values and, in most cases, the character of variation of studied characteristics. Over an area of 1 x 1 m dynamics of characteristics of species diversity coincide in forests of the studied types. Regardless of forest type within the area of 100 m2 species richness recovered 30 years after the fire (i.e. 3–5 times earlier than the establishment of the complete stabilization of the forest structure). That means that floristic composition of the forest remained unchanged from 30 to 210 years after the fire.

  • Gorshkov, E-mail: vg@mm.unknown (email)
  • Bakkal, E-mail: ib@mm.unknown
article id 5591, category Article
Egbert Beuker, Seppo Kellomäki, Marja Kolström. (1996). Changes in wood production of Picea abies and Pinus sylvestris under a warmer climate: comparison of field measurements and results of a mathematical model. Silva Fennica vol. 30 no. 2–3 article id 5591. https://doi.org/10.14214/sf.a9236
Keywords: Pinus sylvestris; climate change; Picea abies; simulation model; global warming; provenance trials
Abstract | View details | Full text in PDF | Author Info

To project the changes in wood production of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) in Finland as a result of climate change, two separate studies were made. The first study, at the Faculty of Forestry, University of Joensuu, based its projections on mathematical models; the second one, at the Finnish Forest Research Institute, based projections on measurements of wood production in two series of aged provenance experiments. The results of the two studies were similar for both species: after a 4°C increase of the annual mean temperature a drastic increase in wood production in northern Finland, but little effect, or even some decrease in the southern part of the country. However, the assumptions used in the two studies differed. One important difference was that in the models the temperature is assumed to be increasing gradually over the years, whereas in the provenance experiments, climate changed immediately when the seedlings were transferred to the planting sites. Another problem with the provenance experiments is that when material is moved in a north-south direction in Finland, not only temperature but also photoperiod changes markedly. To compare these two studies, site factors (e.g. soil type, temperature, precipitation) and silvicultural factors (e.g. plant spacing, survival, time of thinning, thinning intensity) from the provenance experiments were included a variable in the mathematical models.

  • Beuker, E-mail: eb@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Kolström, E-mail: mk@mm.unknown
article id 5590, category Article
Heikki Hänninen, Seppo Kellomäki, Ilkka Leinonen, Tapani Repo. (1996). Overwintering and productivity of Scots pine in a changing climate. Silva Fennica vol. 30 no. 2–3 article id 5590. https://doi.org/10.14214/sf.a9235
Keywords: Pinus sylvestris; climate change; ecosystems; frost damage; phenology; forest ecology; gap-type model; model accuracy; model realism; overvintering
Abstract | View details | Full text in PDF | Author Info

The productivity of Scots pine (Pinus sylvestris L.) under changing climatic conditions in the southern part of Finland was studied by scenario analysis with a gap-type forest ecosystem model. Standard simulations with the model predicted an increased rate of growth and hence increased productivity as a result of climatic warming. The gap-type model was refined by introducing an overwintering sub-model describing the annual growth cycle, frost hardiness, and frost damage of the trees. Simulations with the refined gap-type model produced results conflicting with those of the standard simulation, i.e., drastically decreased productivity caused by mortality and growth-reducing damage due to premature dehardening in the changing climate. The overwintering sub-model was tested with frost hardiness data from Scots pine saplings growing at their natural site 1) under natural conditions and 2) under elevated temperature condition, both in open-top chambers. The model predicted the frost hardiness dynamics quite accurately for the natural conditions while underestimating the frost hardiness of the saplings for the elevated temperature conditions. These findings show that 1) the overwintering sub-model requires further development, and 2) the possible reduction of productivity caused by frost damage in a changing climate is less drastic than predicted in the scenario analysis. The results as a whole demonstrated the need to consider the overwintering of trees in scenario analysis carried out with ecosystem model for boreal conditions. More generally, the results revealed a problem that exists in scenario analysis with ecological models: the accuracy of a model in predicting the ecosystem functioning under present climatic condition does not guarantee the realism of the model, nor for this reason the accuracy for predicting the ecosystem functioning under changing climatic conditions. This finding calls for the continuous rigorous experimental testing of ecological models used for assessing the ecological implications of climatic change.

  • Hänninen, E-mail: hh@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Leinonen, E-mail: il@mm.unknown
  • Repo, E-mail: tr@mm.unknown
article id 5588, category Article
Vadim V. Gorshkov, Irene J. Bakkal, Natalie I. Stavrova. (1996). Postfire recovery of forest litter in Scots pine forests in two different regions of boreal zone. Silva Fennica vol. 30 no. 2–3 article id 5588. https://doi.org/10.14214/sf.a9233
Keywords: Pinus sylvestris; boreal forests; Scots pine; Kola peninsula; Russian Federation; fire ecology; forest litter; Western Siberia; postfire recovery
Abstract | View details | Full text in PDF | Author Info

Investigations carried out in the Kola peninsula (northern taiga) and in the South-western part of Western Siberia (southern taiga and forest-steppe) revealed identical course of the postfire restoration process of forest litter thickness in Scots pine (Pinus sylvestris L.) forests. Despite the differences in mean annual temperature (2°C) and other climatic characteristics the recovery time for thickness of forest litter in both regions amounts to 90–100 years after fire in pine forests of lichen site type and 120–140 years – in green moss type; the thickness of forest litter therewith corresponds 3–4 cm and 7–8 cm respectively. That mean that within the natural borders of pine forests, communities of a specific type possess uniform characteristics of restoration. On the basis of empirical data, it appears that the predicted increase of mean annual temperature of earth surface by (2°C) will not bring changes into the character of postfire recovery of forest litter thickness. It was shown that during the period of the recovery, which spans about 90 years after fire in pine forests of lichen and green moss-lichen site types and 140 years in ones of green moss site types, the rate of increasing of carbon store in the forest litter averaged 0.6 t ha-1 year-1, 0.1 t ha-1 year-1 and 0.2 t ha-1 year-1, respectively.

  • Gorshkov, E-mail: vg@mm.unknown (email)
  • Bakkal, E-mail: ib@mm.unknown
  • Stavrova, E-mail: ns@mm.unknown
article id 5585, category Article
Päivi Lyytikäinen, Jarmo K. Holopainen, Pirjo Kainulainen, Anne Nerg, Seppo Neuvonen, Tarmo Virtanen. (1996). Performance of pine sawflies under elevated tropospheric ozone. Silva Fennica vol. 30 no. 2–3 article id 5585. https://doi.org/10.14214/sf.a9230
Keywords: Pinus sylvestris; Neodiprion sertifer; air pollution; ozone; Gilpinia pallida; resin acids
Abstract | View details | Full text in PDF | Author Info

Concentration of the phytotoxic air pollutant, ozone (O3) is continually increasing in the lower layer of the troposphere. The purpose of this study was to compare performance of pine sawflies on Scots pine (Pinus sylvestris L.) seedlings in ambient and future levels of ozone. Scots pine seedlings were grown in field fumigation system where the ozone doses in fumigated plots were 1.5–1.6 times the ambient level. Larvae of the European pine sawfly (Neodiprion sertifer Geoffroy and Gilpinia pallida Klug) were reared on the foliage of Scots pine. The levels of resin acids and monoterpenes in foliage were analysed. There were no significant effects of ozone fumigation on sawfly performance or levels of defence compounds in pine foliage. The results suggest that the elevated ozone concentrations do not strongly affect the needle quality of young Scots pine and the importance of these two diprionid sawfly species forest pests.

  • Lyytikäinen, E-mail: pl@mm.unknown (email)
  • Holopainen, E-mail: jh@mm.unknown
  • Kainulainen, E-mail: pk@mm.unknown
  • Nerg, E-mail: an@mm.unknown
  • Neuvonen, E-mail: sn@mm.unknown
  • Virtanen, E-mail: tv@mm.unknown
article id 5584, category Article
Tarmo Virtanen, Seppo Neuvonen, Pekka Niemelä, Ari Nikula, Martti Varama. (1996). Climate change and the risks of Neodiprion sertifer outbreaks on Scots pine. Silva Fennica vol. 30 no. 2–3 article id 5584. https://doi.org/10.14214/sf.a9229
Keywords: Pinus sylvestris; climate change; GIS; Neodiprion sertifer; cold tolerance; winter temperatures; insect outbreaks
Abstract | View details | Full text in PDF | Author Info

The European Pine Sawfly (Neodiprion sertifer Geoffroy) is one of the most serious defoliators of Scots pine (Pinus sylvestris L.) in northern Europe. We studied the pattern in the regional occurrence of the outbreaks of N. sertifer in Finland in years 1961-90, and made predictions about the outbreak pattern to the year 2050 after predicted winter warming. We tested whether minimum winter temperatures and forest type and soil properties could explain the observed outbreak pattern. We analysed outbreak patterns at two different spatial levels: forest board- and municipal-level.

The proportion of coniferous forests on damage-susceptible soils (dry and infertile sites) explained a significant part of the variation in outbreak frequency at small spatial scale (municipalities) but not at large spatial scale (forest boards). At the forest board level, the incidence of minimum temperatures below -36 °C (= the critical value for egg mortality) explains 33% of the variation in the outbreak pattern, and at the municipal level the incidence of cold winters was also the most significant explaining variable in northern Finland. Egg mortality due to cold winters seems to be the most parsimonious factor explaining why there have been so few N. sertifer outbreaks in northern and north-eastern Finland. We predict that climate change (increased winter temperatures) may increase the frequency of outbreaks in eastern and northern Finland in the future.

  • Virtanen, E-mail: tv@mm.unknown (email)
  • Neuvonen, E-mail: sn@mm.unknown
  • Niemelä, E-mail: pn@mm.unknown
  • Nikula, E-mail: an@mm.unknown
  • Varama, E-mail: mv@mm.unknown
article id 5583, category Article
Ilkka Leinonen, Heikki Hänninen, Tapani Repo. (1996). Testing of frost hardiness models for Pinus sylvestris in natural conditions and in elevated temperature. Silva Fennica vol. 30 no. 2–3 article id 5583. https://doi.org/10.14214/sf.a9228
Keywords: Pinus sylvestris; climate change; frost hardiness; Scots pine; temperature; dynamic models; photoperiod; climatic warming
Abstract | View details | Full text in PDF | Author Info

Two dynamic models predicting the development of frost hardiness of Finnish Scots pine (Pinus sylvestris L.) were tested with frost hardiness data obtained from trees growing in the natural conditions of Finland and from an experiment simulating the predicted climatic warming. The input variables were temperature in the first model, and temperature and night length in the second. The model parameters were fixed on the basis of previous independent studies. The results suggested that the model which included temperature and photoperiod as input variables was more accurate than the model using temperature as the only input variable to predict the development of frost hardiness in different environmental conditions. Further requirements for developing the frost hardiness models are discussed.

  • Leinonen, E-mail: il@mm.unknown (email)
  • Hänninen, E-mail: hh@mm.unknown
  • Repo, E-mail: tr@mm.unknown
article id 5580, category Article
Virpi Palomäki, Toini Holopainen, Seppo Kellomäki, Kaisa Laitinen. (1996). First-year results on the effects of elevated atmospheric CO2 and O3 concentrations on needle ultrastructure and gas exchange responses of Scots pine saplings. Silva Fennica vol. 30 no. 2–3 article id 5580. https://doi.org/10.14214/sf.a9225
Keywords: Pinus sylvestris; climate change; Scots pine; CO2; ozone; needle ultrastructure; gas exhange
Abstract | View details | Full text in PDF | Author Info

The effects of realistically elevated O3 and CO2 concentrations on the needle ultrastructure and photosynthesis of ca. 20-year-old Scots pine (Pinus sylvestris L.) saplings were studied during one growth period in open-top field chambers situated on a natural pine heath at Mekrijärvi, in eastern Finland. The experiment included six different treatments: chamberless control, filtered air, ambient air and elevated O3, CO2 and O3 + CO2. Significant increases in the size of chloroplast and starch grains were recorded in the current-year needles of the saplings exposed to elevated CO2 These responses were especially clear in the saplings exposed to elevated O3 + CO2 concentrations. These treatments also delayed the winter hardening process in cells. In the shoots treated with O3, CO2 and combined O3 + CO2 the Pmax was decreased on average by 50% (ambient CO2) and 40% (700 ppm CO2). Photosynthetic efficiency was decreased by 60% in all the treated shoots measured under ambient condition and by 30% in the CO2 and O3 + CO2 treated shoots under 700 ppm. The effect of all the treatments on photosynthesis was depressive which was probably related to evident accumulation of starch in the chloroplasts of the pines treated with CO2 and combined O3 + CO2. But in O3 treated pines, which did not accumulate starch in comparison to pines subjected to ambient air conditions, some injuries may be already present in the photosynthetic machinery.

  • Palomäki, E-mail: vp@mm.unknown (email)
  • Holopainen, E-mail: th@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
  • Laitinen, E-mail: kl@mm.unknown
article id 5578, category Article
Mika Aurela, Tuomas Laurila, Juha-Pekka Tuovinen. (1996). Measurements of O3, CO2 and H2O fluxes over a Scots pine stand in eastern Finland by the micrometeorological eddy covariance method. Silva Fennica vol. 30 no. 2–3 article id 5578. https://doi.org/10.14214/sf.a9223
Keywords: Pinus sylvestris; Scots pine; CO2; ecosystem; eddy covariance technique; net carbon balance; ozone deposition; rnicrometeorology
Abstract | View details | Full text in PDF | Author Info

The eddy covariance technique is a novel micrometeorological method that enables the determination of the atmosphere-biosphere exchange rate of gases such as ozone and carbon dioxide on an ecosystem scale. This paper describes the technique and presents results from the first direct measurements of turbulent fluxes of O3, CO2 and H2O above a forest in Finland. The measurements were performed during 15 July-5 August 1994 above a Scots pine (Pinus sylvestris L.) stand near the Mekrijärvi research station in Eastern Finland.

The expected diurnal cycles were observed in the atmospheric fluxes of O3, CO2 and H2O. The data analysis includes interpretation of the O3 flux in terms of the dry deposition velocity and evaluation the dependency of the net CO2 flux on radiation. The eddy covariance method and the established measurement system has proved suitable for providing high-resolution data for studying ozone deposition to a forest as well as the net carbon balance and related physiological processes of an ecosystem.

  • Aurela, E-mail: ma@mm.unknown (email)
  • Laurila, E-mail: tl@mm.unknown
  • Tuovinen, E-mail: jt@mm.unknown
article id 5574, category Article
Jouni Vettenranta. (1996). Effect of species composition on economic return in a mixed stand of Norway spruce and Scots pine. Silva Fennica vol. 30 no. 1 article id 5574. https://doi.org/10.14214/sf.a9219
Keywords: Pinus sylvestris; Picea abies; net present value; mixed forests; growth models; tree species composition; forest management practices; felling methods; valuation; soil expectation value; treatment programme
Abstract | View details | Full text in PDF | Author Info

The effect of species mixture was studied in a mixed stand of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) by simulating around 100 different treatment schedules during the rotation in a naturally regenerated even-aged stand located on a site of medium fertility in North Karelia, Finland. Both thinning from below and thinning from above were applied. Optimum rotations were determined by maximising the net present value calculated to infinity and different treatment schedules were compared with the net present value over one rotation as per rotation applied. In the optimum treatment programme, the proportion of pines was decreased by half of the basal area in the first thinning stage and by the end of the rotation to about one third. In thinning from above, the proportion of pines can be maintained at a slightly higher level. It is economically profitable to maintain the growing stock capital at approximately the level recommended by Forest Centre Tapio, a semi-governmental forestry authority. With non-optimum species composition, the loss in net present value over one rotation can be about 10 % in thinning from below and about 20 % in thinning from above.

  • Vettenranta, E-mail: jv@mm.unknown (email)
article id 5573, category Article
Ilkka Vanha-Majamaa, Raili Suominen, Tiina Tonteri, Eeva-Stiina Tuittila. (1996). Seedling establishment after prescribed burning of a clear-cut and a partially cut mesic boreal forest in southern Finland. Silva Fennica vol. 30 no. 1 article id 5573. https://doi.org/10.14214/sf.a9218
Keywords: Pinus sylvestris; Betula pendula; Picea abies; Betula pubescens; natural regeneration; seedling establishment; prescribed burning; controlled burning; Sorbus aucuparia; seed dispersal; mesic forest; seed rain; autoregression model; GLM
Abstract | View details | Full text in PDF | Author Info

The prescribed burning of a 7.3 ha clear-cut and a 1.7 ha partially cut forest (volume 150 m3/ha) was carried out in Evo (61 °12'N, 25°07'E) on 1 June 1992. The forest was a mesic Myrtillus site type forest dominated by Norway spruce (Picea abies (L.) H. Karst.). Practically all the trees and the above-ground parts of the understorey vegetation died in the fire, while the mor layer was thinned by an average of 1.5 cm.

A study was made on the change of germinated seedling population in time and their dependence on environmental factors. Seedlings of Norway spruce, Scots pine (Pinus sylvestris L.), silver birch (Betula pendula Roth), pubescent birch (B. pubescens Ehrh.) and rowan (Sorbus aucuparia L.) were inventoried in 1993 and in 1994 on permanent plots, four times per growing season. Autoregression models were used to compare regeneration of tree species in the burned forest with regeneration in the burnt clear-cut area, and to study the effect of distance from nearest seed source to regeneration.

The average number of seedlings germinating in 1993 was higher than in 1994, probably because of differences between these consecutive years in regard to the amount of seed rain and weather conditions. The number of Norway spruce and rowan seedling was higher inside the forest area than in the clear-cut area. The distance to the bordering forest and to the closest seed tree did not explain the result. It is suggested that the more stable microclimatic conditions under the shade of dead tree promote germination and seedling establishment in the forest area. As rowan is a bird-dispersed species, it is likely that dead trees help the dispersal of rowan seed by providing birds place to sit and defecate. The shade provided by dead trees may influence the further succession of the tree stand and vegetation composition and diversity.

  • Vanha-Majamaa, E-mail: iv@mm.unknown (email)
  • Suominen, E-mail: rs@mm.unknown
  • Tonteri, E-mail: tt@mm.unknown
  • Tuittila, E-mail: et@mm.unknown
article id 5571, category Article
Katarina Lindgren, Dag Lindgren. (1996). Germinability of Norway spruce and Scots pine pollen exposed to open air. Silva Fennica vol. 30 no. 1 article id 5571. https://doi.org/10.14214/sf.a9216
Keywords: Pinus sylvestris; Picea abies; gene flow; pollen; pollen viability; conifer pollen
Abstract | View details | Full text in PDF | Author Info

Germination of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) pollen decreased during exposure to open air conditions. Usually more than half of the pollen remained germinative after a few days outdoors, but following more than four days outdoors the germination became very low. This study supports the opinion that pollen in the atmosphere remains viable long enough to allow for long-distance gene flow by pollen migration, as an important factor in genetic management of conifers and in evolution, maintaining diversity and potential for adaptation.

  • Lindgren, E-mail: kl@mm.unknown (email)
  • Lindgren, E-mail: dl@mm.unknown
article id 5563, category Article
Margaret Penner, Hannu Hökkä, Timo Penttilä. (1995). A method for using random parameters in analyzing permanent sample plots. Silva Fennica vol. 29 no. 4 article id 5563. https://doi.org/10.14214/sf.a9214
Keywords: Pinus sylvestris; drained peatlands; drainage; competition; sampling; random parameters
Abstract | View details | Full text in PDF | Author Info

The use of random parameter models in forestry has been proposed as one method of incorporating different levels of information into prediction equations. By explicitly considering the variance-covariance structure of observations and considering some model parameters as random rather than fixed, one can incorporate more complex error structures in analysing data.

Competition indices and variance component techniques were applied to 92 Scots pine (Pinus sylvestris L.) -dominated permanent sample plots on drained peatlands in Northern Finland. By quantifying stand, plot, and tree level variation, it was possible to identify the level (stand, plot or tree) at which the explanatory variables contributed to the model. The replication of plots within stands revealed little variation among plots within a single stand but significant variation occurred at stand and tree levels. Positive and negative effects of inter-tree competition are identified by examining simple correlation statistics and the random parameter model.

  • Penner, E-mail: mp@mm.unknown (email)
  • Hökkä, E-mail: hh@mm.unknown
  • Penttilä, E-mail: tp@mm.unknown
article id 5561, category Article
Jari Liski. (1995). Variation in soil organic carbon and thickness of soil horizons within a boreal forest stand – effect of trees and implications for sampling. Silva Fennica vol. 29 no. 4 article id 5561. https://doi.org/10.14214/sf.a9212
Keywords: Pinus sylvestris; soil carbon; spatial variation; soil formation; soil morphology; tree effects; soil sampling; geostatics
Abstract | View details | Full text in PDF | Author Info

Spatial variation in the density of soil organic carbon (kg/m2) and the thickness of soil horizons (F/H, E) were investigated in a 6 m x 8 m area in Scots pine (Pinus sylvestris L.) stand in Southern Finland for designing an effective sampling for the C density and studying the effect of trees on the variation. The horizon thickness of the podzolized soil were measured on a total of 126 soil cores (50 cm deep) and the C density of the organic F/H and 0–10 cm, 10–20 cm and 20–40 cm mineral soil layers was analysed.

The C density varied 3–5 fold within the layers and the coefficients of variation ranged from 22 % to 40%. Considering the gain in confidence per sample, 8–10 samples were suggested for estimating the mean C density in the F/H and 0–40 cm layers, although about 30 samples are needed for 10% confidence in the mean. The C densities and horizon thicknesses were spatially dependent within the distances of 1–8 m, the spatial dependence accounting for 43–86% of the total variance. The F/H layer was thicker and contained more C within 1–3 m radius from trees. In the 10–20 cm and 20–40 cm layers (B horizon) the C density also increased towards the trees, but more pronouncedly in the immediate vicinity of the stems. Because the spatial patterning of the E horizon thickness was similar, the increase was attributed to stemflow and precipitation of organic compounds in the podzol B horizon.

  • Liski, E-mail: jl@mm.unknown (email)
article id 5559, category Article
Jari Hynynen. (1995). Predicting the growth response to thinning for Scots pine stands using individual-tree growth models. Silva Fennica vol. 29 no. 3 article id 5559. https://doi.org/10.14214/sf.a9210
Keywords: Pinus sylvestris; thinnings; height; diameter; stem form; growth models; individual-tree; distance-dependent
Abstract | View details | Full text in PDF | Author Info

Individual tree-growth models for diameter and height, and a model for the cylindrical stem form factor are presented. The aims of the study were to examine modelling methods in predicting growth response to thinning, and to develop individual-tree, distance-independent growth models for predicting the development of thinned and unthinned stands of Scots pine (Pinus sylvestris L.). The models were constructed to be applicable in simulation systems used in practical forest management planning. The models were based on data obtained from eleven permanent thinning experiments located in even-aged Scots pine stands in Southern and Central Finland.

Two alternative models were developed to predict tree diameter growth in thinned and unthinned stands. In the first model, the effect of stand density was described using stand basal area. In the alternative model, an explicit variable was incorporated referring to the relative growth response due to thinning. The magnitude of the growth response was expressed as a function of thinning intensity. The Weibull function was employed to describe the temporal distribution of the thinning response. Both models resulted in unbiased predictions in unthinned and in moderately thinned stands. An explicit thinning variable was needed for unbiased growth prediction in heavily thinned stands, and in order to correctly predict the dynamics of the growth response.

In the height growth model, no explicit thinnning variable referring thinning was necessary for growth prediction in thinned stands. The stem form factor was predicted using the model that included tree diameter and tree height as regressor variables. According to the results obtained, the information on the changes in the diameter/height ratio following the thinning is sufficient to predict the change in stem form.

  • Hynynen, E-mail: jh@mm.unknown (email)
article id 5557, category Article
Klaus Silfverberg. (1995). Forest regeneration on nutrient-poor peatlands: Effects of fertilization, mounding and sowing. Silva Fennica vol. 29 no. 3 article id 5557. https://doi.org/10.14214/sf.a9208
Keywords: Pinus sylvestris; Betula; soil preparation; natural regeneration; drained peatlands; mounding; ground vegetation; sowing; seedling number
Abstract | View details | Full text in PDF | Author Info

The effects of wood ash and PK fertilization on natural regeneration and sowing of Scots pine (Pinus sylvestris L.) were studied in field experiments on nitrogen-poor (Ntot 0.87–1.26%) peat substrates. The study material was derived from three drained, nutrient-poor pine mires (64°52’ N, 25°08’ E) at Muhos, near Oulu, Finland. The experimental fields were laid out in 1985 as a split-split-plot design including the following treatments; mounding, natural regeneration and sowing and fertilization; PK (400 kg ha-1) and wood ash (5,000 kg ha-1). The seedlings were inventoried in circles in July–August 1991.

Changes in the vegetation were small and there were no statistical differences due to the fertilization treatments in the ground vegetation. PK or ash fertilization did not cause vegetation changes harmful to Scots pine regeneration on nitrogen-poor peatlands. Both sowing and fertilization significantly increased the number of pine seedlings, but not their height. Wood ash increased seedling number more than PK fertilizer. The number of seedlings varied from 7,963 (control) to 42,781 ha-1 (mounding + sowing + ash). The seedling number was adequate for successful regeneration even on non-mounded, non-fertilized naturally regenerated plots.

The number of birch seedlings varied more than that of pine (370–25,927 ha-1). Mounding especially increased the number of birches. The difference between PK fertiliser and ash was less pronounced than that for pine. In addition, to the field studies the effects of ash and PK fertilizer on the germination of Scots pine seeds was studied in a greenhouse experiment. Soaking in ash solutions strongly reduced seed germination, while the PK solution was less harmful.

  • Silfverberg, E-mail: ks@mm.unknown (email)
article id 5556, category Article
Timo J. Hokkanen, Erkki Järvinen, Timo Kuuluvainen. (1995). Properties of top soil and the relationship between soil and trees in a boreal Scots pine stand. Silva Fennica vol. 29 no. 3 article id 5556. https://doi.org/10.14214/sf.a9207
Keywords: Pinus sylvestris; carbon; nitrogen; spatial patterns; respiration; organic matter; ecological field theory; soil characteristics
Abstract | View details | Full text in PDF | Author Info

One-hectare plot in a Scots pine (Pinus sylvestris L.) forest was systemically sampled for surface soil characteristics: humus layer thickness, soil carbon and nitrogen content, pH, electrical conductivity and respiration were determined from 106 samples. The effects of large trees on the plot were mapped and their joint influences at the locations of soil sampling were described as the influence potential, derived from the ecological field theory, and were calculated based on the locations and dimensions of trees.

The range of variation of soil characteristics was from three to sevenfold; no spatial autocorrelation was detected. The calculated influence potential of trees, as determined by their size and spatial distribution, was related to the spatial variation of top soil properties. Top soil properties were also related to thickness of the humus layer but they were poorly correlated with underlying mineral soil characteristics. Humus layer thickness, with the calculated influence potential of trees, may provide a means to predict top soil characteristics in specific microenvironments in the forest floor.

  • Hokkanen, E-mail: th@mm.unknown (email)
  • Järvinen, E-mail: ej@mm.unknown
  • Kuuluvainen, E-mail: tk@mm.unknown
article id 5552, category Article
Liisa Saarenmaa, Timo Leppälä. (1995). Fill-in seedlings in constituting the stocking of Scots pine stands in northern Finland. Silva Fennica vol. 29 no. 2 article id 5552. https://doi.org/10.14214/sf.a9203
Keywords: Pinus sylvestris; planting; spatial pattern; artificial regeneration; fill planting; survival of seedlings
Abstract | View details | Full text in PDF | Author Info

Fill planting is a common procedure following reforestation in Finland. In 1990, 13% of the total of seedlings planted was used for fill planting. The objective of this study is (i) to survey the survival of fill-in seedlings and (ii) to estimate the spatial pattern of stands to evaluate the importance of fill-in seedlings in constituting the stocking of Scots pine (Pinus sylvestris L.) stands in Central and Northern Finland.

A survey of 63 artificially regenerated Scots pine stands was conducted in 1990. Stand densities varied from 950 to 3,925 seedlings/ha. The mean densities of originally planted, fill planted and naturally regenerated seedlings were 863, 639 and 791/ha, respectively. The survival of originally planted seedlings was 36% and that of fill-in seedlings 48%. Death rate of fill-in seedlings of Scots pine increased with longer times between original and fill planting. The survival rate of Norway spruce (Picea abies) seedlings was correlated with temperature sum. Height of the fill-in seedlings was less than that of the originally planted ones. Most stands had an even spatial distribution with the exception of sparsely populated stands, which were somewhat clustered. This indicates that dying of seedlings is not randomly spread. Because of poor survival, fill planting seems to be a risky business in most cases.

  • Saarenmaa, E-mail: ls@mm.unknown (email)
  • Leppälä, E-mail: tl@mm.unknown
article id 5545, category Article
Jouni Siipilehto, Olavi Lyly. (1995). Weed control trials with fibre mulch, glyphosate and terbuthylazine in Scots pine plantations. Silva Fennica vol. 29 no. 1 article id 5545. https://doi.org/10.14214/sf.a9196
Keywords: Pinus sylvestris; herbicides; glyphosate; terbuthylazine; weed control; seedling stands; mulches
Abstract | View details | Full text in PDF | Author Info

The following treatments were compared in three Scots pine (Pinus sylvestris L.) reforestation areas on a scarified moist mineral-soil site in southern Finland, planted with 1+1 bareroot stock in spring 1987: (a) no weed control treatment; (b) mulching with a fibre slurry produced by mixing wastepaper with water and applied 1 cm deep to an area of 60 cm in diameter around the seedling soon after planting; (c) glyphosate (at 2 kg ha-1) sprayed on a 1 m2 spot around the seedling in early August 1987; (d) terbuthylazine (at 10 kg ha-1) applied as (c). Monitoring of the trials over a 4-year period between 1987–90 showed that none of the treatments reduced surface vegetation to an extent that would have benefited pine. The percentage cover development of the vegetation, dominated by Agrostis capillaris, Calamagrostis arundinaceae, Deschampsia flexuosa, Festuca ovina, Epilobioum angustifolium and Pteridium aquillinum, followed much the same pattern in all treatments, with (c) slightly favouring forbs. Survival of pine at the end of the study period was about 90%, with non-significant differences between treatments. Mulching and terbuthylazine treatment slightly reduced seedling height growth in the second year. Growth was better in glyphosate treatment than in terbuthylazine treatment in the lowest (<30%) and the highest (>60%) pre-treatment weed cover classes, and in the latter also better than in untreated control. Mulching gave variable results; at its best it provided also good control of weeds for several years, without, however, improving the initial development of pine in these trials.

  • Siipilehto, E-mail: js@mm.unknown (email)
  • Lyly, E-mail: ol@mm.unknown
article id 5543, category Article
Matti Haapanen. (1995). Within-plot subsampling of trees for assessment in progeny trials of Scots pine. Silva Fennica vol. 29 no. 1 article id 5543. https://doi.org/10.14214/sf.a9194
Keywords: Pinus sylvestris; efficiency; sampling; progeny testing; plot size; non-contiguous plots; statistical analysis
Abstract | View details | Full text in PDF | Author Info

Tree height data from 33 progeny trials of Scots pine (Pinus sylvestris L.) were used to determine the effect of within-plot subsampling on the magnitude of statistically detectable differences between families, family heritability and correlation of family means based on different sample sizes. The results indicated that in trials established with a standard plot configuration of 25 trees per plot, measuring only 10–15 trees gives nearly the same precision as with assessment of all the plot trees. Even as few as 4–6 trees assessed per plot may constitute a sufficient sample if families or parental trees of extreme performance are being selected. Trials established with non-contiguous plots were found to be more efficient than those established using multiple-tree contiguous plots.

  • Haapanen, E-mail: mh@mm.unknown (email)
article id 5540, category Article
Anders Persson. (1994). How genotype and silviculture interact in forming timber properties. Silva Fennica vol. 28 no. 4 article id 5540. https://doi.org/10.14214/sf.a9180
Keywords: Pinus sylvestris; Picea abies; silviculture; wood properties; spacing; genotypes
Abstract | View details | Full text in PDF | Author Info

Independent of genotype, increased spacing results in increased branch diameter of Scots pine (Pinus sylvestris L.), but on different levels for different genotypes. Frequency of defects like spike knots and crooked stems are under stronger genetic than silvicultural control. Simultaneous improvement of rate of growth and timber properties is feasible. Deteriorating of both factors can happen rapidly at a negative selection. A defect like stem cracking of Norway spruce (Picea abies (L.) H. Karst.) only manifests itself under drought stress when certain genetic and environmental prerequisites are present, like high fertility and wide spacing. This emphasize the fact that new silvicultural methods may reveal genetic weaknesses.

  • Persson, E-mail: ap@mm.unknown (email)
article id 5530, category Article
Anna Saarsalmi, Erkki Lipas, Jouni Mikola, Teijo Nikkanen, Eira-Maija Savonen. (1994). Effect of fertilization on flowering and seed crop in Scots pine seed orchards. Silva Fennica vol. 28 no. 3 article id 5530. https://doi.org/10.14214/sf.a9170
Keywords: Pinus sylvestris; fertilization; germination; flowering; seed orchards; clones; seed crop; weight
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to obtain information needed in preparing more precise fertilization recommendations for seed orchards. The fertilization requirement was estimated on basis of soil and needle analyses, and by investigating the effects of different fertilization treatments on male and female flowering, size of seed crop and seed quality.

The study was carried out in two Scots pine (Pinus sylvestris L.) seed orchards in Southern Finland, one established on forest soil in 1971 and 1972, and the other on a peat field in 1974. 10 clones and 39 grafts from each clone were selected randomly from both orchards in autumn 1985. The treatments consisted of N, P and K in various combinations, micronutrients, wood ash and grass control. The orchards were fertilized in spring 1986.

There were statistically significant differences between the clones in both orchards as regards amount of flowers, size of the seed crop and seed quality. The annual variation in flowering and the size of the seed crop was also large. In general, the seeds from cones collected in October matured well and their germination percentage was high. The effects of fertilization on flowering, the size of seed crop and seed quality were small. It would appear that the size of the crop can be affected to a much greater extent by favouring clones with a high seed-producing capacity than through fertilization. Fertilization is unnecessary if the nutrient status of the soil is satisfactory.

  • Saarsalmi, E-mail: as@mm.unknown (email)
  • Lipas, E-mail: el@mm.unknown
  • Mikola, E-mail: jm@mm.unknown
  • Nikkanen, E-mail: tn@mm.unknown
  • Savonen, E-mail: es@mm.unknown
article id 5529, category Article
Jukka Lippu. (1994). Patterns of dry matter partitioning and 14C-photosynthate allocation in 1.5-year-old Scots pine seedlings. Silva Fennica vol. 28 no. 3 article id 5529. https://doi.org/10.14214/sf.a9169
Keywords: Pinus sylvestris; carbon; photosynthesis; root growth; allocation; shoot growth; 14C-incorporation; dry matter partitioning
Abstract | View details | Full text in PDF | Author Info

Change in dry matter partitioning, 14C-incorporation, and sink 14C-activity of 1.5-year-old Scots pine (Pinus sylvestris L.) seedlings grown in growth chamber conditions were studied during a 91-day experiment. On five sampling dates, seedlings were labelled with 14CO2 and whole-plant allocation patterns were determined. Intensively growing shoots modified the dry matter partitioning: during shoot growth the proportion of roots decreased but after that it increased. Based on their large proportion of dry matter, the needles (excluding current needles) were the strongest sink of carbon containing 40% of the incorporated 14C. Despite their small initial sink size, the elongating shoots (current main shoot + current branch) and their needles were the second strongest sink (30–40% of the total 14C) which reflects their high physiological activity. The proportion of 14C in the current year’s main shoot increased during shoot growth but decreased as the growth began to decline after 70 days. 10–20% of the total assimilated 14C was translocated to the roots. Laterals above 2nd order were the strongest sink in the root system, containing twice as much 14C as the other roots together. Alternation between shoot and root growth can be seen clearly: carbon allocation to roots was relatively high before and after the period of intensive shoot growth. Changes in root sink strength resulted primarily from changes in root sink activity rather than sink size.

  • Lippu, E-mail: jl@mm.unknown (email)
article id 5402, category Article
Risto Jalkanen, Juha Kaitera. (1994). Gremmeniella abietina produces pycnidia in cankers of living shoots with green needles on Scots pine. Silva Fennica vol. 28 no. 2 article id 5402. https://doi.org/10.14214/sf.a9168
Keywords: Pinus sylvestris; Gremmeniella abietina; disease resistance; lifecycle; pycnidia
Abstract | View details | Full text in PDF | Author Info

A Gremmeniella abietina (Lagerb.) race of type A was found to produce pycnidia in cankers of previous year’s shoots (1991) on branches of Scots pine (Pinus sylvestris L.) bearing green needles and living buds in the current-year shoots (1992) with no apparent symptoms of infection by G. abietina. The restricted colonization of green shoots by G. abietina, with only restricted canker development, may indicate that older, slow-growing natural Scots pines of the northern boreal forests resists the fungus well. However, the ability of the fungus to survive and even sporulate in such cankers indicates one way of surviving over consecutive years otherwise unfavourable for it.

  • Jalkanen, E-mail: rj@mm.unknown (email)
  • Kaitera, E-mail: jk@mm.unknown
article id 5397, category Article
Juha Kaitera, Risto Jalkanen. (1984). Old and fresh Gremmeniella abietina damage on Scots pine in eastern Lapland in 1992. Silva Fennica vol. 28 no. 2 article id 5397. https://doi.org/10.14214/sf.a9166
Keywords: Pinus sylvestris; Gremmeniella abietina; shoots; fungal damage; assessment; plant diseases
Abstract | View details | Full text in PDF | Author Info

Damage on Scots pine (Pinus sylvestris L.) caused by Gremmeniella abietina (Lagerb.) Morelet was assessed in the summer of 1992 in 67 stands in eastern Lapland. The area and severity of damage were smaller and lighter than had earlier been estimated and occurred especially in stands in the first-thinning stage or in middle-age. Significant new infection of 1991 occurred in stands previously heavily infected by G. abietina near Kemihaara river, lake Naruska, the Naruska river, the Tuntsa river and lake Vilma. Fresh damage occurred mainly in the lower or middle parts of the Scots pine canopies.

  • Kaitera, E-mail: jk@mm.unknown (email)
  • Jalkanen, E-mail: rj@mm.unknown
article id 5525, category Article
Jari Miina. (1994). Spatial growth model for Scots pine on drained peatland. Silva Fennica vol. 28 no. 1 article id 5525. https://doi.org/10.14214/sf.a9159
Keywords: Pinus sylvestris; drained peatlands; growth models; linear models
Abstract | View details | Full text in PDF | Author Info

A spatial growth model is presented for Scots pine (Pinus sylvestris L.) on a dwarf-shrub pine mire drained 14 years earlier. The growth model accounts for the variation in tree diameter growth owing to the competition between trees, the distance between tree and ditch, and the time passed since drainage. The model was used to study the effect of tree arrangement on the post-drainage growth of a pine stand. Clustering of trees decreased the volume growth by 9–20% as compared to a regular spatial distribution. Stand volume growth, for a given number of stems, was at its maximum and variation in diameter growth at its minimum when the stand density on the ditch border was 1.5–5 higher than midway between two adjacent ditches.

  • Miina, E-mail: jm@mm.unknown (email)
article id 5521, category Article
Taneli Kolström, Seppo Kellomäki. (1993). Tree survival in wildfires. Silva Fennica vol. 27 no. 4 article id 5521. https://doi.org/10.14214/sf.a15682
Keywords: Pinus sylvestris; forest fires; Picea abies; Betula spp.; Finland; mortality
Abstract | View details | Full text in PDF | Author Info

The survival of forest tree species in wildfires was examined on two burned stands. Norway spruce (Picea abies (L.) H. Karst.) and birches (Betula spp.) proved to be sensitive to the effects of wildfire; almost all individuals of these tree species were killed by the fires. Scots pine (Pinus sylvestris L.) was more tolerable to the effects of wildfire; i.e. one out of five Scots pines survived. Fire tolerance increased as tree size increased.

The PDF includes an abstract in Finnish.

  • Kolström, E-mail: tk@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
article id 5520, category Article
Kari T. Korhonen. (1993). Mixed estimation in calibration of volume functions of Scots pine. Silva Fennica vol. 27 no. 4 article id 5520. https://doi.org/10.14214/sf.a15681
Keywords: Pinus sylvestris; models; forest inventories; volume; estimation
Abstract | View details | Full text in PDF | Author Info

Regression models for estimating stem volume of Scots pine (Pinus sylvestris L.) were constructed using sample tree data measured in the 7th and 8th National Forest Inventory of Finland. Stem volume were regressed on diameter, basal area of growing stock, and geographic location. The results of the study show that using second order trend surface to describe the geographic variation of the residuals gives satisfactory results. Using mixed estimation for combining old and new sample tree data improves the efficiency of an inventory. The weight of the prior information must be low, because remarkable differences in stem form was found in the two inventories.

The PDF includes an abstract in Finnish.

  • Korhonen, E-mail: kk@mm.unknown (email)
article id 5518, category Article
Heikki Hänninen, Seppo Kellomäki, Kaisa Laitinen, Brita Pajari, Tapani Repo. (1993). Effect of increased winter temperature on the onset of height growth of Scots pine: a field test of a phenological model. Silva Fennica vol. 27 no. 4 article id 5518. https://doi.org/10.14214/sf.a15679
Keywords: Pinus sylvestris; height growth; frost damage; bud burst; climatic change
Abstract | View details | Full text in PDF | Author Info

According to a recently presented hypothesis, the predicted climatic warming will cause height growth onset of trees during mild spells in winter and heavy frost damage during subsequent periods of frost in northern conditions. The hypothesis was based on computer simulations involving a model employing air temperature as the only environmental factor influencing height growth onset. In the present study, the model was tested in the case of eastern Finnish Scots pine (Pinus sylvestris L.) saplings. Four experimental saplings growing on their natural site were surrounded by transparent chambers in autumn 1990. The air temperature in the chambers was raised during the winter to present an extremely warm winter under the predicted conditions of a double level of atmospheric carbon dioxide. The temperature treatment hastened height growth onset by two months as compared to the control saplings, but not as much as expected on the basis of the previous simulation study. This finding suggests that 1) the model used in the simulation study needs to be developed further, either by modifying the modelled effect of air temperature or by introducing other environmental factors, and 2) the predicted climatic warming will not increase the risk of frost damage in trees as much as suggested by the previous simulation study.

The PDF includes an abstract in Finnish.

  • Hänninen, E-mail: hh@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Laitinen, E-mail: kl@mm.unknown
  • Pajari, E-mail: bp@mm.unknown
  • Repo, E-mail: tr@mm.unknown
article id 5513, category Article
Tapani Pöykkö, Pirkko Velling. (1993). Inheritance of the narrow-crowned Scots pine E 1101, "Kanerva pine". Silva Fennica vol. 27 no. 3 article id 5513. https://doi.org/10.14214/sf.a15674
Keywords: Pinus sylvestris; crown form; ideotypes; phenotypes; monogenic inheritance
Abstract | View details | Full text in PDF | Author Info

There is some evidence to support the hypothesis that crown form of Scots pine (Pinus sylvestris L.) can be inherited either mono- or polygenically. In Finland, a narrow, horizontal whorl-layer structure is striking in about one half of the offspring of a genotype E 1101, ”Kanerva pine”. The offspring are characterized by a narrow crown, short and thin branches at an angle of 90° to the stem, minimal tapering and by numerous long, lateral shoots, long needles and the common occurrence of three-needled fascicles among the dwarf shoots. These features are connected to a high growth rate, a high harvest index and to tortuosity of the stem. It is suggested that this complex of characters is determined by a single dominant gene.

In this study, several offspring of the E 1101 were classified into three form types in seven sets of progeny test data, including progenies of various ages having E 1101 as either maternal or paternal parent as well as open pollinated progenies of second-generation offspring. A segregation close to 1:1 was found both in the first and in the second-generation progenies when wilds and intermediates were combined and compared with Kanervas. The result indicates that the three types of Kanerva form can be due to a single dominant allele (K). Kanervas are heterozygous (Kk) for the allele and wilds are recessive homozygotes (kk) resulting 1:1 segregation in their progenies. However, there were also remarkable deviations from the expected distribution. The differences as well as the inheritance pattern are discussed.

The PDF includes an abstract in Finnish.

  • Pöykkö, E-mail: tp@mm.unknown (email)
  • Velling, E-mail: pv@mm.unknown
article id 5512, category Article
Christian Messier, Pasi Puttonen. (1993). Coniferous and non-coniferous fine-root and rhizome production in Scots pine stands using the ingrowth bag method. Silva Fennica vol. 27 no. 3 article id 5512. https://doi.org/10.14214/sf.a15673
Keywords: Pinus sylvestris; ground vegetation; undergrowth; roots; root systems; fine-root production; ingrowth bag; rhizomes; underwood
Abstract | View details | Full text in PDF | Author Info

Coniferous and non-coniferous fine root and rhizome production was measured after one growing season using the ingrowth bag method in Scots pine (Pinus sylvestris L.) stands differing in ages from 7 to 105 years in Southern Finland. Total fine-root production decreased from the 7-year to 20-year-old stands, and then increased slightly in the 85- to 105-year-old stands. Most of the total fine-root biomass in the youngest age groups came from non-conifer species, whereas most of the total fine-root biomass in the three older age groups came from conifer species. The maximum coniferous fine-root production was found to occur at crown closure in the 11- to 13-year-old stands. Rhizome production was the lowest and highest in the 20- and 85- to 105-year-old stands, respectively. The increase in rhizome production in the 85- to 105-year-old stands was associated with an abundant understory cover of Vaccinium myrtillus and V. vitis-idaea and an increase in light penetration. The ingrowth bag method was found to be useful in assessing the relative fine-root production among species-group and successional stages of Scots pine stands.

The PDF includes an abstract in Finnish.

  • Messier, E-mail: cm@mm.unknown (email)
  • Puttonen, E-mail: pp@mm.unknown
article id 5510, category Article
Esa Koistinen, Sauli Valkonen. (1993). Models for height development of Norway spruce and Scots pine advance growth after release in southern Finland. Silva Fennica vol. 27 no. 3 article id 5510. https://doi.org/10.14214/sf.a15671
Keywords: Pinus sylvestris; Picea abies; Finland; growth models; advance growth; release cut
Abstract | View details | Full text in PDF | Author Info

Mixed linear models were constructed to describe the height development of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) advance growth after release cutting. The models related density of the overstory, time elapsed since release cutting and tree size with annual height increment. Parameters of preliminary models were estimated from a limited data set to judge the feasibility of the approach for further studies.

The PDF includes an abstract in Finnish.

  • Koistinen, E-mail: ek@mm.unknown (email)
  • Valkonen, E-mail: sv@mm.unknown
article id 5506, category Article
Risto Heikkilä, Sauli Härkönen. (1993). Moose (Alces alces L.) browsing in young Scots pine stands in relation to the characteristics of their winter habitats. Silva Fennica vol. 27 no. 2 article id 5506. https://doi.org/10.14214/sf.a15667
Keywords: Pinus sylvestris; deciduous trees; Scots pine; Alces alces; mixed forests; landscape ecology; moose; feeding behaviour; carrying capacity; browsing
Abstract | View details | Full text in PDF | Author Info

Moose (Alces alces L.) browsing was studied in young Scots pine (Pinus sylvestris L.) stands mixed with deciduous trees in high-density winter ranges. The proportional use of twig biomass decreased as the availability increased. The total as well as proportional biomass consumption were higher on the moist than on the dry type of forest. The per tree consumption of pine was higher on the moist type, where the availability of pine was lower. Deciduous trees were more consumed on the moist type, where their availability was relatively high. The consumption of pine saplings increased as the availability of birch increased. Pine stem breakages were most numerous when birch occurred as overgrowth above pine and at high birch densities. The availability of other deciduous tree species did not correlate with browsing intensity of Scots pine. Moose browsing had seriously inhibited the development of Scots pines in 6% of the stands, over 60% of available biomass having been removed. Rowan and aspen were commonly over-browsed and their height growth was inhibited, which occurred rarely by birch. There was no difference in the proportion of young stands in forest areas with high and low moose density. A high proportion of peatland forests was found to indicate relatively good feeding habitats in the high-density areas.

The PDF includes an abstract in Finnish.

  • Heikkilä, E-mail: rh@mm.unknown (email)
  • Härkönen, E-mail: sh@mm.unknown
article id 5505, category Article
Heli Peltola, Jorma Aho, Alpo Hassinen, Seppo Kellomäki, Matti Lemettinen. (1993). Swaying of trees as caused by wind: analysis of field measurements. Silva Fennica vol. 27 no. 2 article id 5505. https://doi.org/10.14214/sf.a15666
Keywords: Pinus sylvestris; wind; windspeed; wind loads; dynamic load; bending
Abstract | View details | Full text in PDF | Author Info

Measurements of wind and subsequent swaying of two Scots pines (Pinus sylvestris L.) were made at stand edge conditions. The horizontal windspeed was measured ten meters outside of the stand edge for four heights using cup anemometers. The compass directions were determined using a directional vane placed above the canopy. Tree swaying was measured by accelerometers at xy-coordinates. The shape of the wind profile at the stand edge varied to some degree depending on windspeed, but the form was a logarithmic one. Swaying of trees increased along with increasing windspeed. Furthermore, swaying was more or less irregular in relation to xy-coordinates, but it occurred, however, mainly perpendicularly to the direction of mean windspeed. The maximum bending of trees to the direction of mean windspeed varied also only little for various gusting windspeeds (average windspeed of 20 seconds) and dynamic wind loads. The maximum bending of trees was also in most cases less or equal to those predicted on the basis of static wind loads, when the mean windspeed for static load is taken as equal to the gusting windspeed.

The PDF includes an abstract in Finnish.

  • Peltola, E-mail: hp@mm.unknown (email)
  • Aho, E-mail: ja@mm.unknown
  • Hassinen, E-mail: ah@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
  • Lemettinen, E-mail: ml@mm.unknown
article id 5504, category Article
Heli Peltola, Seppo Kellomäki. (1993). A mechanistic model for calculating windthrow and stem breakage of Scots pines at stand age. Silva Fennica vol. 27 no. 2 article id 5504. https://doi.org/10.14214/sf.a15665
Keywords: Pinus sylvestris; wind; stems; breakage; windspeed; breaking stress; bending models
Abstract | View details | Full text in PDF | Author Info

A model for the mechanism of windfall and stem breakage was constructed for single Scots pine (Pinus sylvestris L.) at the stand edge. The total turning moment arising from the wind drag and from the bending of stem and crown was calculated along with the breaking stress of the stem. Similarly, the support given by the root -soil plate anchorage was calculated. Windspeed variation within the crown and the vertical distribution of stem and crown weight were taken into account. Model computations showed that trees having a large height to diameter ratio were subjected to greater risk of falling down or breaking than trees with a small height to diameter ratio. The windspeed required to blow down a tree or break the stem of a tree decreased if the height to diameter ratio or the crown to stem ratio of trees increased.
The PDF includes an abstract in Finnish.

  • Peltola, E-mail: hp@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
article id 5495, category Article
Hannu Salminen, Martti Varmola. (1993). Influence of initial spacing and planting design on the development of young Scots pine (Pinus sylvestris L.) stands. Silva Fennica vol. 27 no. 1 article id 5495. https://doi.org/10.14214/sf.a15656
Keywords: Pinus sylvestris; yield; Scots pine; planting; spacing; quality
Abstract | View details | Full text in PDF | Author Info

Three Scots pine (Pinus sylvestris L.) plantations carrying 35 plots with initial spacings from 800 to 5,000 plants/ha were studied. Planting designs varied from a square to a rectangle with 5-metre row distance, the plant-to-plant distance being 0.8 metres. At current dominant height of 6 m, rectangularity had no effect on height, diameter, or volume growth of trees. Slight ovality of stems was observed in rectangular plots but the differences in the cross-wise mean diameters were very small, not over 1.1 mm in terms of plot-wise means. The diameter of the thickest living branch of a tree was linearly dependent of the dbh. The branches were clearly thicker between the planting rows at under 1,600 stems/ha stand density. A non-square planting pattern is a conceivable alternative when the line corridors suitable for mechanized silvicultural operations are preferred.
The PDF includes an abstract in Finnish.

  • Salminen, E-mail: hs@mm.unknown (email)
  • Varmola, E-mail: mv@mm.unknown
article id 5494, category Article
Jari Nieppola. (1993). Site classification in Pinus sylvestris L. forests in southern Finland. Silva Fennica vol. 27 no. 1 article id 5494. https://doi.org/10.14214/sf.a15655
Keywords: Pinus sylvestris; Scots pine; forest soils; Southern Finland; forest types; site classification; TWINSPAN
Abstract | View details | Full text in PDF | Author Info

It was examined whether the present site classification method, and especially its applicability to site productivity estimation, could be improved in upland Scots pine (Pinus sylvestris L.) forests in Southern Finland by developing a classification key based on Two-way Indicator Species Analysis (TWINSPAN), and/or by inclusion of soil texture, stoniness and the humus layer depth more closely in the classification method. TWINSPAN clusters (TW) explained 71%, and forest site types (FST) 64% of the variation in site index (SI) (H100). When soil texture (TEXT) was added to the regression model, the explanatory power increased to 82% (SI = TW + TW * TEXT) and to 80% (SI = FST + FST * TEXT), respectively. Soil texture alone explained 69% of the variation in site index. The influence of stoniness on site index was significant (P <0.05) on sorted medium sand soils and on medium and fine sand moraine soils. The thickness of the humus layer (2–6 cm) was not significantly (P=0.1) related to site index.

It is suggested that the proposed TWINSPAN classification cannot replace the present forest site type system in Scots pine stands in Southern Finland. However, the TWINSPAN key may be used to aid the identification of forest types. The observation of dominant soil texture within each forest type is recommended.

The PDF includes an abstract in Finnish.

  • Nieppola, E-mail: jn@mm.unknown (email)
article id 5490, category Article
Timo Pukkala, Jari Karsikko, Taneli Kolström. (1992). A spatial model for the diameter of thickest branch of Scots pine. Silva Fennica vol. 26 no. 4 article id 5490. https://doi.org/10.14214/sf.a15651
Keywords: Pinus sylvestris; simulation; timber quality; competition; stand density; spatial pattern
Abstract | View details | Full text in PDF | Author Info

The model predicts the base diameter of the thickest living branch of a tree growing in a planted or naturally regenerated even-aged stand. A mixed model type was used in which the residual variation was divided into within-stand and between-stand components. The study material consisted of 779 trees measured in 12 plots located in 20 to 35 years old Scots pine (Pinus sylvestris L.) stands (breast height age 10 to 20 years). Branch diameter was closely connected to the breast height diameter of the stem. In a stand of a certain age, competition by close neighbours slightly decreased branch diameter in a given diameter class. According to the model, the greatest difference is between trees subjected to very little competition and those subjected to normal competition. The model was used in simulated stands with varying age, density, and tree arrangement. The simulations showed that trees with rapid diameter growth at young age had thicker branches at a given breast height diameter than trees with slower diameter growth. However, a very slow growth rate did not produce trees with branches thinner than those possessing a medium growth rate.
The PDF includes an abstract in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
  • Karsikko, E-mail: jk@mm.unknown
  • Kolström, E-mail: tk@mm.unknown
article id 5488, category Article
Matti Haapanen. (1992). Effect of plot size and shape on the efficiency of progeny tests. Silva Fennica vol. 26 no. 4 article id 5488. https://doi.org/10.14214/sf.a15649
Keywords: Pinus sylvestris; efficiency; progeny testing; plot size; statistical methods; experimental design
Abstract | View details | Full text in PDF | Author Info

A simulation approach was applied to study the pattern of environmental variability and the relative statistical efficiency of 14 different plot types. The study material consisted of two nine-year-old field tests of Scots pine (Pinus sylvestris L.). The area of the test sites was 1.57 and 0.67 hectares. The efficiency was measured as the error variance attached to the estimate of family mean and the total size of a test needed to detect a given, least significant difference between two family means. The statistical efficiency tended to decline along with increasing plot size. The importance of plot shape was negligible compared to plot size. The highest efficiency was obtained with single-tree plots. Non-contiguous plots appeared to be considerably more efficient than block plots of equal size. The effects of intergenotypic competition on the choice of plot type are discussed.

The PDF includes an abstract in Finnish

  • Haapanen, E-mail: mh@mm.unknown (email)
article id 5487, category Article
Maarit Kytö. (1992). Lygus bugs as agents of growth disorders in permethrin-treated pine seedlings in regeneration areas. Silva Fennica vol. 26 no. 4 article id 5487. https://doi.org/10.14214/sf.a15648
Keywords: Pinus sylvestris; growth disorders; seedlings; Lygus; permethrin; bud disorders
Abstract | View details | Full text in PDF | Author Info

The ability of Lygus bugs to cause growth disorders in permethrin-treated Scots pine (Pinus sylvestris L.) seedlings after planting was studied in two regeneration areas. There were three treatments: exposure of the seedlings to Lygus, mechanical protection of the seedlings from insects, and control seedlings. There were no significant differences in the rate of growth disorders between the treatments. The permethrin application protected the seedlings against Lygus bugs in the early summer, as well as when the bug abundance was low. The development of these seedlings, as well as the multiple-leadered and bushy seedlings on a third regeneration area, was followed for two years. Multiple leaders reduced height growth and bud number of a seedling, but caused marked losses in growth only when the seedlings still had multiple leaders the following year, or when they formed several, equally developed stems.
The PDF includes an abstract in Finnish.

  • Kytö, E-mail: mk@mm.unknown (email)
article id 5486, category Article
Kari Löyttyniemi, Risto Heikkilä, Seppo Repo. (1992). Pine tar in preventing moose browsing. Silva Fennica vol. 26 no. 3 article id 5486. https://doi.org/10.14214/sf.a15647
Keywords: Pinus sylvestris; Scots pine; Alces alces; repellent; moose; browsing damage; control
Abstract | View details | Full text in PDF | Author Info

The efficacy of pine tar as a moose (Alces alces L.) contact repellent was tested in young Scots pine (Pinus sylvestris L.) stands suffering from moose damage in Southern Finland during the winter 1981–82. Application of tar to shoots by spraying protected the trees satisfactorily throughout the winter.

The PDF includes an abstract in Finnish.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
  • Heikkilä, E-mail: rh@mm.unknown
  • Repo, E-mail: sr@mm.unknown
article id 5483, category Article
Erkki Verkasalo. (1992). Relationships of the modulus of elasticity and the structure of Finnish Scots pine wood. Silva Fennica vol. 26 no. 3 article id 5483. https://doi.org/10.14214/sf.a15644
Keywords: Pinus sylvestris; wood properties; wood anatomy; wood structure; tracheids; modulus of elascticity; stereology
Abstract | View details | Full text in PDF | Author Info

The paper presents preliminary results on the relationships of the longitudinal modulus of elasticity (E) in bending, based on ISO Standard 3349 tests on small, clear specimens, and some basic characteristics of Finnish Scots pine (Pinus sylvestris L.) wood. A manual image analysis method – quantitative stereological counting – was introduced and applied for the investigations of wood structure.

The main results were consistent with those from the prior research. The range of E was 9.7 to 19.1 GPa. Increase in especially fibre density index (R2 = 0.95), weight density and specific gravity (R2 = 0.90), Runkel’s ratio, coefficient of cell rigidity and number of growth rings per cross-sectional unit area, but also in latewood percentage (R2 = 0.58) resulted in an increase in E. Increase in growth ring width, particularly in the width of the late wood section within a ring (R2 = 0.63 to 0.90) had a reverse effect. Cell wall thickness did not show any clear effect. Except for tracheid diameter, the relationships were stronger for the variables determined in the tangential than in the radial wood direction.

Quantitative stereological counting has been used to some degree in the Finnish wood research. The procedure is technically feasible and easy to use. A large sample of counting areas is frequently needed to obtain accurate mean results for the size and distribution of the features. Because the actual analysis points are located at a fixed distance from each other, the method is not in principle well suited for wood with a regular and simple structure, as Scots pine. However, the good correlations between E and some characteristics obtained with stereological counting did not support this misgiving.

The PDF includes an abstract in Finnish.

  • Verkasalo, E-mail: ev@mm.unknown (email)
article id 5482, category Article
Heljä-Sisko Helmisaari. (1992). Spatial and age-related variation in nutrient concentrations of Pinus sylvestris needles. Silva Fennica vol. 26 no. 3 article id 5482. https://doi.org/10.14214/sf.a15643
Keywords: Pinus sylvestris; spatial variation; nutrients; sampling; nutrient concentration; conifer needles
Abstract | View details | Full text in PDF | Author Info

Spatial and age-related variation in nutrient concentrations of Scots pine (Pinus sylvestris L.) needles was studied during 1984–86 in three stands of different stages of development. The dry weight of current needles was significantly (p < 0.05) higher in the tree top than in a composite sample representing the whole crown. However, there were no significant differences in the concentrations of nutrients in needles between upper and lower crown levels. The concentrations of mobile nutrients N, P, K and Mg decreased with increasing needle age whereas the concentrations of poorly mobile nutrients Ca, Mn and Fe increased during needle ageing. The coefficient of variation for nutrient concentrations varied irregularly when only a few trees were sampled but stabilized when tree number was ten or more.
The PDF includes an abstract in Finnish.

  • Helmisaari, E-mail: hh@mm.unknown (email)
article id 5481, category Article
Pekka Nygren, Pertti Hari. (1992). Effect of foliar application with acid mist on the photosynthesis of potassium-deficient Scots pine seedlings. Silva Fennica vol. 26 no. 3 article id 5481. https://doi.org/10.14214/sf.a15642
Keywords: Pinus sylvestris; photosynthesis; nutrient deficiency; seedlings; acid deposition; potassium concentration
Abstract | View details | Full text in PDF | Author Info

The interactive effects of potassium deficit and foliar application with acid water (pH 5.5, 4.5, 4.0 and 3.0 given consecutively) on CO2 exchange rate of Pinus sylvestris L. seedlings was investigated in field conditions. No reduction of the CO2 exchange rate was observed in the seedlings supplied with sufficient potassium. Only the seedlings having the lowest needle K concentration (2.4 mgg-1) had an apparently low CO2 exchange rate before the applications with acid water. The CO2 exchange rate of most of the seedlings with low needle K concentration (3.9–6.0 mgg-1) decreased after the acid water application. The threshold acidity for the reduction varied between pH 4,0 and 3.0 depending on the needle K concentration. The reduction was more apparent at high irradiance. It was concluded that acid precipitation disturbs the CO2 exchange only in conditions of mineral nutrient deficit.

The PDF includes an abstract in Finnish.

  • Nygren, E-mail: pn@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
article id 5478, category Article
Seppo Kellomäki, Marja Kolström. (1992). Computations on the management of seedling stands of Scots pine under the influence of changing climate in southern Finland. Silva Fennica vol. 26 no. 2 article id 5478. https://doi.org/10.14214/sf.a15639
Keywords: Pinus sylvestris; forest management; models; Betula pendula; Scots pine; silver birch; simulation; climatic change; seedling stands
Abstract | View details | Full text in PDF | Author Info

Model computations on the management of Scots pine (Pinus sylvestris L.) at the seedling stage showed that a rising temperature due to the suggested climate change could increase the competition capacity of birch species (Betula pendula) more than Scots pine, whose growth could even decline during the course of a rise in temperature. A temperature rise could, thus, bring the time of removal of birches forward when aiming at Scots pine timber stands composed of these tree species. The increasing proportion of birches makes the removal of birches even more urgent and emphasizes the need for careful management of Scots pine stands under rising temperatures. The first thinning of Scots pine is generally brought forward; this is particularly the case when wide spacing is applied in planting. A furthrer rise in temperature magnifies the above patterns by reducing further the competitive capacity of Scots pine in relation to birches.
The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Kolström, E-mail: mk@mm.unknown
article id 5476, category Article
Jukka Selander, Auli Immonen. (1992). Effect of fertilization and watering of Scots pine seedlings on the feeding preference of the pine weevil (Hylobius abietis L.). Silva Fennica vol. 26 no. 2 article id 5476. https://doi.org/10.14214/sf.a15637
Keywords: Pinus sylvestris; fertilization; pine weevil; water stress; Hylobius abietis; seedlings; feeding preference
Abstract | View details | Full text in PDF | Author Info

Two-year-old containerized Scots pine (Pinus sylvestris L.) seedlings, raised under different fertilization and watering regimes, were subjected to feeding preference tests with pine weevils (Hylobius abietis L.) in a bioassay. In the tests carried out with pairs of seedlings, the weevil preferred water-stressed seedlings to well-watered ones. In the case of well-watered seedlings, the weevil caused significantly more damage to NPK-fertilized seedlings than those given pure PK fertilization, or no fertilization at all. It is apparent that PK fertilization reduces, and water stress increases seedling susceptibility to weevil damage. The results support findings from field trials that water stress (planting shock) predisposes seedlings to weevil damage. Weevil resistance is discussed with respect to fertilization and water stress as determinants of seedling quality.

The PDF includes an abstract in Finnish.

  • Selander, E-mail: js@mm.unknown (email)
  • Immonen, E-mail: ai@mm.unknown
article id 5475, category Article
Jyrki Hytönen. (1992). Allelopathic potential of peatland plant species on germination and early seedling growth of Scots pine, silver birch and downy birch. Silva Fennica vol. 26 no. 2 article id 5475. https://doi.org/10.14214/sf.a15636
Keywords: Pinus sylvestris; Betula; seedling growth; seed germination; alleopathy
Abstract | View details | Full text in PDF | Author Info

The potential alleopathic inhibitive effects of aqueous extracts of 13 peatland plant species on germination, radicle and seedling growth of Scots pine (Pinus sylvestris L.), silver and downy birch (Betula pendula Roth., B. pubescens Ehrh.) were studied. Freshly cut plant parts were finely ground, mixed with distilled water and agitated. The proportions of fresh plant mass in the mass-based extracts varied within the range of 1, 5, 10 and 20% (w/w). The seeds were germinated in petri dishes moistened with the plant extracts. In a separate experiment growth of birch seedlings irrigated with the extracts was studied.

Ledum palustre, Vaccinium uliginosum and Empetrum nigrum extracts, and in certain experiments extracts of other species, inhibited the germination of Scots pine and birch seeds. Results from the different experiments were not, however, fully consistent. None of the low (1% w/w) extract concentrations had any effect on germination. Strong extract concentrations (20% w/w) inhibited germination of pine seedlings significantly. The extracts affected only slightly the growth of potted birch seedlings.

The PDF includes an abstract in Finnish.

  • Hytönen, E-mail: jh@mm.unknown (email)
article id 5469, category Article
Risto Heikkilä, Kari Löyttyniemi. (1992). Growth response of young Scots pines to artificial shoot breaking simulating moose damage. Silva Fennica vol. 26 no. 1 article id 5469. https://doi.org/10.14214/sf.a15627
Keywords: Pinus sylvestris; height growth; timber quality; Alces alces; stems; diameter growth; breakage; moose damage
Abstract | View details | Full text in PDF | Author Info

The main stem of young Scots pine (Pinus sylvestris L.) trees was cut off halfway along the current leading shoot and the two previous years’ leading shoots to simulate moose (Alces alces) damage. Trees of the same size were chosen as controls before treatments. The experiment was inspected ten years after artificial stem breakage. Removing the current leading shoot and the second shoot did not essentially affect the height and diameter growth of the trees. Removal down to the third shoot reduced the height as well as diameter growth. The average loss in growth was equivalent to less than one year’s growth. When the stem was cut off at the second or third shoot, stem crookedness and the presence of knots resulted in stem defects that will subsequently reduce the sawtimber quality. A high proportion of the stem defects will obviously still be visible at the first thinning cutting. Removing injured trees as pulpwood and pruning the remaining parts of cut stems evidently improves the quality of pine stand with moose damage.

The PDF includes an abstract in Finnish.

  • Heikkilä, E-mail: rh@mm.unknown (email)
  • Löyttyniemi, E-mail: kl@mm.unknown
article id 5463, category Article
Öje Danell. (1991). Survey of past, current and future Swedish forest tree breeding. Silva Fennica vol. 25 no. 4 article id 5463. https://doi.org/10.14214/sf.a15621
Keywords: Pinus sylvestris; Betula pendula; Picea abies; Sweden; Pinus contorta; seed orchards; forest tree breeding; breeding programmes
Abstract | View details | Full text in PDF | Author Info

The paper gives an introduction of the tree breeding program of Sweden that started in 1936 by the establishment of an association for the tree breeding. In 1967 the Institute of Forest Improvement was founded and it replaced the earlier association. The main species in the programme have been Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.), lately also birch (mainly Betula pendula Roth.) and lodgepole pine (Pinus contorta). In addition, limited breeding has been done also with hybrid aspen (Populus tremula x P. tremuloides), oak (Quercus), larch (Larix), black spruce (Picea mariana) and a few other native and exotic species. The dominating initial effort has been to select plustrees in natural stands and use them for production of reforestation material. In addition, a considerable body of tests was built. The paper lists the status of breeding material of the different tree species and introduces the medium and short-term breeding programmes.

  • Danell, E-mail:
article id 5446, category Article
Hannu Ilvesniemi. (1991). Spatial and temporal variation of soil chemical characteristics in pine sites in Southern Finland. Silva Fennica vol. 25 no. 2 article id 5446. https://doi.org/10.14214/sf.a15600
Keywords: Pinus sylvestris; sampling; soil properties; soil acidity; exchangeable cations; soil acidification
Abstract | View details | Full text in PDF | Author Info

In producing time series of soil properties, there are many technical and statistical problems which need to be taken into account when sampling and analysing the measurement data. In field the reliable localization of sample plots and the precise distinction of different soil layers are important to reduce the variance caused by the sampling procedure. In laboratory the use of same extraction salt, sample pretreatment procedure and filter paper throughout a measurement series is important. The remarkable small-scale variation within a sampling plot leads to a need of a large number of samples to be collected.

In this study, no trends attributable to soil acidification in the contents of exchangeable base cations could be found among the years 1982, 1985 and 1988. However, in eluvial and illuvial layers the pH decreased and the content of extractable H+ increased during this period. In illuvial layer also the content of extractable aluminium increased.

The PDF includes an abstract in Finnish.

  • Ilvesniemi, E-mail: hi@mm.unknown (email)
article id 5443, category Article
Raimo Silvennoinen, Rauno Hämäläinen, Kaarlo Nygrén, Kim von Weissenberg. (1991). Spectroradiometric characteristics of Scots pine and intensity of moose browsing. Silva Fennica vol. 25 no. 2 article id 5443. https://doi.org/10.14214/sf.a15597
Keywords: Pinus sylvestris; Scots pine; Alces alces; aerial photography; moose; spectral analysis; reflectance; multispectral photography; browsing
Abstract | View details | Full text in PDF | Author Info

The light reflected from the crowns of Scots pine (Pinus sylvestris L.) clones was measured spectroradiometrically during and after growing season. Standard deviations of the spectra of pine clones showing differences in moose browsing intensity were compared. A new algorithm was developed for predicting the browsing intensity of moose (Alces alces).

The PDF includes an abstract in Finnish.

  • Silvennoinen, E-mail: rs@mm.unknown (email)
  • Hämäläinen, E-mail: rh@mm.unknown
  • Nygrén, E-mail: kn@mm.unknown
  • Weissenberg, E-mail: kw@mm.unknown
article id 5438, category Article
Juha Heiskanen, Hannu Raitio. (1991). Maan vesipotentiaali paljasjuuristen männyntaimien taimitarhakasvatuksessa. Silva Fennica vol. 25 no. 1 article id 5438. https://doi.org/10.14214/sf.a15592
English title: Soil water potential during the production of bare-rooted Scots pine seedlings.
Original keywords: mänty; taimitarhat; maavesi; vesipotentiaali; maan ilmatila; harsokate
English keywords: Pinus sylvestris; water retention; nurseries; tensiometer; air space; matric potential
Abstract | View details | Full text in PDF | Author Info

The matrix potential, measured with tensiometers, and its effect on the soil air-water ratio were examined during the production of bare-rooted Scots pine (Pinus sylvestris L.) seedlings in nursery fields. Soil water potential was monitored during the growing season of 1983 at three nurseries in Finland, and from fields growing various seedling types at depths of 10 and 20 cm. In 1986, soil core samples were collected in order to assess the water desorption characteristics of the soil. In addition, the effect of polypropylene gauze covering (Agryl P 17) on the soil water potential was examined during the growing season of 1985 at two nurseries in Finland at depths of 5, 10 and 15 cm.

The soil water potential was relatively high in all the fields studied. In fields growing one- and two-year-old seedlings, the median potential was higher than -10 kPa. The potential did not fall below the limit of the measured scale (ca. -85 kPa) of the tensiometers. Soil aeriation may have been periodically insufficient in the rooting zone, as a result of high water content. The favourable water potential is below -5 to – 6 kPa. The gauze covering slightly (1–4 kPa) increased the soil water potential, an effect which could be harmful if the soil air space is low. During the second growing season, the soil water potential was lower in the fields covered by the gauze during the first year than in the fields without the covering.

The PDF includes an abstract in English.

  • Heiskanen, E-mail: jh@mm.unknown (email)
  • Raitio, E-mail: hr@mm.unknown
article id 5437, category Article
Tapani Repo. (1991). Rehardening potential of Scots pine seedlings during dehardening. Silva Fennica vol. 25 no. 1 article id 5437. https://doi.org/10.14214/sf.a15591
Keywords: Pinus sylvestris; frost resistance; acclimatization; quiescence; impedance
Abstract | View details | Full text in PDF | Author Info

The ability of one-year old Scots pine (Pinus sylvestris L.) seedlings to reharden during the dehardening period was studied. Naturally hardened quiescent seedlings were preconditioned at 0°C for ten days and then placed in chambers at different forcing temperatures with different light regimes. The forcing periods were followed by cool periods. Changes in frost hardiness were monitored at intervals using freeze tests of whole plants. Frost hardiness was assessed by three methods: impedance, survival and growth retardation. Dehardening seemed to be a partially reversible process, i.e. in some growing conditions slight rehardening was found.

The PDF includes an abstract in Finnish.

  • Repo, E-mail: tr@mm.unknown (email)
article id 5436, category Article
Leena Finér. (1991). Root biomass on an ombrotrophic pine bog and the effects of PK and NPK fertilization. Silva Fennica vol. 25 no. 1 article id 5436. https://doi.org/10.14214/sf.a15590
Keywords: Pinus sylvestris; fertilization; peatlands; ground vegetation; root biomass
Abstract | View details | Full text in PDF | Author Info

Scots pine (Pinus sylvestris L.) living root biomass (ø≤ 10 mm) was 640 g/m2 on the studied low-shrub pine bog before fertilization, and that of the ground vegetation almost the same. The total root necromass was 23% of the biomass of living roots. The length of the pine roots was 2,440 m/m2. The biomass of living roots and root necromass were mostly located in the top 20 cm layer of the soil. The ø < 1 mm pine root fraction accounted for almost 90% of the pine root length; in contrast, over 50% of the biomass was in the 1–10 mm thick root biomass, pine root length and PK (MgB) fertilization did not affect total living root biomass, pine root length, nor the root necromass during the three-year observation period.

The PDF includes an abstract in Finnish.

  • Finér, E-mail: lf@mm.unknown (email)
article id 5434, category Article
Risto Heikkilä. (1990). Effect of plantation characteristics on moose browsing on Scots pine. Silva Fennica vol. 24 no. 4 article id 5434. https://doi.org/10.14214/sf.a15588
Keywords: Pinus sylvestris; Alces alces; moose; feeding behaviour; browsing damages; plantation characteristics
Abstract | View details | Full text in PDF | Author Info

The effects of plantation characteristics on moose (Alces alces) browsing intensity was studied in 82 Scots pine (Pinus sylvestris L.) plantations in Southern Finland. Moose browsing occurred most commonly in plantations established on relatively fertile soil, and the degree of damage was at highest in plantations with openings. A high amount of brush, especially aspen, increased the risk of damage. Furthermore, damage was intensified in plantations situated on hills, slopes or at a long distance from main roads or settlements.

The PDF includes an abstract in Finnish.

  • Heikkilä, E-mail: rh@mm.unknown (email)
article id 5433, category Article
Marja-Leena Valkonen, Heikki Hänninen, Paavo Pelkonen, Tapani Repo. (1990). Frost hardiness of Scots pine seedlings during dormancy. Silva Fennica vol. 24 no. 4 article id 5433. https://doi.org/10.14214/sf.a15587
Keywords: Pinus sylvestris; frost hardiness; cold hardiness; annual cycle; chilling requirements; bud dormancy; rest
Abstract | View details | Full text in PDF | Author Info

The relationships between bud dormancy and frost hardiness were examined using two-year-old Pinus sylvestris L. seedlings. The chilling temperatures used were +4 and -2°C. To examine the dormancy release of the seedlings, a forcing technique was used. Frost hardiness was determined by artificial freezing treatments and measurements of electrical impedance. At the start of the experiment, the frost hardiness of the seedlings was about -25°C. After the rest break, the seedlings kept at +4°C dehardened until after eight weeks their frost hardiness reached -5°C. At the lower chilling temperature (-2°C) the frost hardiness remained at the original level. When moved from +4 to -2°C, seedlings were able to reharden only after the time required for bud burst in the forcing conditions had reached the minimum.

The PDF includes an abstract in Finnish

  • Valkonen, E-mail: mv@mm.unknown (email)
  • Hänninen, E-mail: hh@mm.unknown
  • Pelkonen, E-mail: pp@mm.unknown
  • Repo, E-mail: tr@mm.unknown
article id 5432, category Article
Risto Rikala, Helen J. Jozefek. (1990). Effect of dolomite lime and wood ash on peat substrate and development of tree seedlings. Silva Fennica vol. 24 no. 4 article id 5432. https://doi.org/10.14214/sf.a15586
Keywords: Pinus sylvestris; Betula pendula; Picea abies; germination; height; nutrients; pH; dry weight; electrical conductivity; Sphagnum peat
Abstract | View details | Full text in PDF | Author Info

Effect of dolomite lime and wood ash (0, 0.5, 1, 2, 4, 8 and 16 kg m-3) on the chemical composition of low humified Sphagnum peat was studied. Germination of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) and silver birch (Betula pendula Roth) and the subsequent growth of these seedlings were investigated in a greenhouse experiment. Nutrient concentrations in shoots and roots of pine seedlings were also analysed. The pH of peat increased asymptotically from 3.8 to about 7.0 with increasing lime regimen and to about 8.0 with increasing ash regimen. Wood ash linearly increased electrical conductivity and P, K, and Ca concentrations of peat. Rate of germination, within 7 days, of pine and spruce was best at low pH (<5) while birch seeds had a slightly higher pH optimum (4–6). Germination capacity, within 21 days, was not affected by pH or application regimen of either lime or ash. Pine and spruce seedlings grew best with lime and ash doses of 0.5–2.0 kg m-3, the pH of peat being 4–5. Lime and ash treatments did not affect the growth of birch seedlings, but wood ash increased nutrient concentration of pine seedlings.

The PDF includes an abstract in Finnish.

  • Rikala, E-mail: rr@mm.unknown (email)
  • Jozefek, E-mail: hj@mm.unknown
article id 5420, category Article
Toyohiro Miyazava, Jukka Laine. (1990). Effect of macroclimate on the development of Scots pine seedling stands on drained oligotrophic pine mires. Silva Fennica vol. 24 no. 2 article id 5420. https://doi.org/10.14214/sf.a15574
Keywords: Pinus sylvestris; fertilization; regeneration; drained peatlands; plantations; ditch spacing; effective temperature sum; microtopography
Abstract | View details | Full text in PDF | Author Info

The influence of different fertilization treatments and ditch spacings on the height growth of young Scots pine (Pinus sylvestris L.) seedling stands growing under various climatic regimes were determined. Comparisons were made between naturally regenerated and planted seedling stands. The effective temperature sum had a stronger effect on the height growth of planted seedlings, and in Northern Finland the planted seedlings seemed to be influenced to a greater degree by the adverse climatic conditions. The heavier the dose of fertilizer that had been applied, the greater the difference in growth caused by macroclimate. A considerably larger proportion of natural seedlings were located on hummocks compared with that of planted seedlings, irrespective of the region. On plots with wider ditch spacings, seedlings growing on hummocks were superior in height growth to those on flat surfaces.

The PDF includes an abstract in Finnish.

  • Miyazava, E-mail: tm@mm.unknown (email)
  • Laine, E-mail: jl@mm.unknown
article id 5414, category Article
Heikki Smolander, Seppo Kellomäki, Pauline Oker-Blom. (1990). Typpipitoisuuden vaikutus männyn neulasten fotosynteesiin ja verson itsevarjostukseen. Silva Fennica vol. 24 no. 1 article id 5414. https://doi.org/10.14214/sf.a15566
English title: The effect of nitrogen concentration on needle photosynthesis and within shoot shading in Scots pine.
Original keywords: mänty; ravinteisuus; fotosynteesi; kasvupaikkatekijät; verson rakenne; säteilyn sitomistehokkuus
English keywords: Pinus sylvestris; photosynthesis; shading; fertility; site factors; shoot structure; light interception efficiency
Abstract | View details | Full text in PDF | Author Info

A close relationship between photosynthetic capacity and nitrogen concentration of leaves is known to exist. In conifers, nitrogen also affects the pattern of mutual shading within a shoot, which is a basic unit used in studying photosynthesis of coniferous trees. These effects of needle nitrogen concentration on photosynthetic capacity and mutual shading of needles were analysed for Scots pine (Pinus sylvestris L.) shoots taken from five young stands growing on sites of different fertility. The effect of nitrogen concentration on needle photosynthesis was studied based on measurements of the photosynthetic radiation response of shoots from which two thirds of the needles were removed in order to eliminate the effect of within shading.

An increase of one percentage unit in nitrogen concentration of needles increased the photosynthetic capacity of needles by 25 mg CO2 dm-2h-1. The effect of nitrogen on within-shoot shading was quantified in terms of the silhouette area to total needle area ratio of a shoot (STAR), which determines the relative interception rate per unit of needle area on the shoot. Although nitrogen promoted needle growth, an increase in nitrogen concentration decreased the within-shoot shading. This effect resulted from a decrease in needle density on the shoot and an increased needle angle with increasing nitrogen content.

The PDF includes an abstract in Finnish.

  • Smolander, E-mail: hs@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Oker-Blom, E-mail: po@mm.unknown
article id 5411, category Article
Eero Paavilainen. (1990). Effect of refertilization of pine and birch stands on a drained fertile mire. Silva Fennica vol. 24 no. 1 article id 5411. https://doi.org/10.14214/sf.a15563
Original keywords: mänty; koivu; turvemaat; ojitetut suot; hieskoivu; jatkolannoitus; hivenravinteet
English keywords: Pinus sylvestris; Betula; fertilization; Betula pubescens; drained peatlands; tree litter; micronutrients
Abstract | View details | Full text in PDF | Author Info

Refertilization with PK, about 15 years after the first fertilizer application, increased tree growth and the amount of nutrients in tree litter in Scots pine (Pinus sylvestris L.) and birch (mainly Betula pubescens Erhr.) stands on a drained fertile mire in Northern Finland (65°34 N’, 25°42’ E). The increase in growth and nutrient contents after refertilization was greatest in the mature pine stand where the application of nitrogen and micronutrients gave an additional response compared to the PK-application.

The PDF includes an abstract in Finnish.

  • Paavilainen, E-mail: ep@mm.unknown (email)
article id 5410, category Article
Markku Nygren. (1990). Männyn ja kuusen siementen massan vaihtelusta. Silva Fennica vol. 24 no. 1 article id 5410. https://doi.org/10.14214/sf.a15562
English title: Variation in the seed mass of Scots pine and Norway spruce.
Original keywords: kuusi; mänty; lämpötila; sademäärä; siementen paino; siementen kypsyminen
English keywords: Pinus sylvestris; Picea abies; precipitation; temperature; seed mass; seed ripening
Abstract | View details | Full text in PDF | Author Info

Seed mass within any plant species is one of the least plastic components of plant structure. The aim of this study was to analyse the variation in the seed mass of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) in relation to three environmental factors: soil fertility, mean temperature and precipitation during seed filling period. Data published earlier on seed mass of these species on different sites and different years was used in the study.

The seed mass of both species was independent of soil fertility (forest type) but did vary between different years. It is hypothesized that if the seed-ripening summer is warmer than average, Scots pine seed mass tends to be smaller. In this study, seed mass varied independently of the amount of precipitation during the ripening summer. However, generalization of the results requires further study.

The PDF includes an abstract in English.

  • Nygren, E-mail: mn@mm.unknown (email)
article id 5406, category Article
Olavi Huuri. (1990). Leikattu paakkutaimi. Silva Fennica vol. 24 no. 1 article id 5406. https://doi.org/10.14214/sf.a15558
English title: The cut-block method for seedling production: birth of an idea.
Original keywords: kuusi; mänty; taimitarhat; leikattu paakkutaimi; paakkutaimet
English keywords: Pinus sylvestris; Picea abies; nurseries; cut-block seedling; container grown plants
Abstract | View details | Full text in PDF | Author Info

The author first introduced the cut-block seedling production method to Finland in 1969. The aim is to raise seedlings whose lateral roots do not become deformed as a result of a restricting container or other external pressure. The seedlings are raised in a large, fairly compact substrate block where the roots can freely develop in a normal fashion. The blocks are then cut up into individual cubes, each containing a seedling. The precise positioning of the sowing point permits mechanization of the work.

The PDF includes an abstract in English.

  • Huuri, E-mail: oh@mm.unknown (email)
article id 5395, category Article
Mirja Kortesharju, Jouko Kortesharju. (1989). Studies on epiphytic lichens and pine bark in the vicinity of a cement works in northern Finland. Silva Fennica vol. 23 no. 4 article id 5395. https://doi.org/10.14214/sf.a15553
Keywords: Pinus sylvestris; bark; lichens; air pollution; heavy metals; calcium; Bryoria; Parmeliopsis; cement; elements
Abstract | View details | Full text in PDF | Author Info

The element content (Ca, Mg, K, Na, Fe, Mn, Zn, Cu, Pb, S) of Scots pine (Pinus sylvestris L.) bark and Bryoria lichens, as well as the occurrence and coverage of epiphytic lichens and the length of Bryoria species, were studied in the vicinity of Kolari cement works, NW Finland. Fruticose Bryoria species had the highest coverage on pine trunks at a distance of 2 km or more from the cement works. At a distance of 1 km the foliose – or even crustose – Parmeliopsis species were most abundant, while nearer to the works lichens were almost completely absent. The length of Bryoria was reduced at distances of less than 2 km from the cement works. The calcium content in Bryoria species increased very steeply close to the works; by a factor of 60 at a distance of 1 km compared to 16 km. No corresponding increase in other elements was observed near the cement works. All the elements studied in pine bark showed a significant negative correlation with distance, and a significant positive correlation with the calculated dust deposition levels. There were only minor differences between the north and south of the pine trunks, or the side facing or away from the works. Pine bark analysis is recommended for element accumulation studies.

The PDF includes an abstract in English.

  • Kortesharju, E-mail: mk@mm.unknown (email)
  • Kortesharju, E-mail: jk@mm.unknown
article id 5391, category Article
Jukka Pietilä. (1989). Shape of Scots pine knots close to the stem pith. Silva Fennica vol. 23 no. 4 article id 5391. https://doi.org/10.14214/sf.a15549
Keywords: Pinus sylvestris; Scots pine; branch diameter; branch angle; knot diameter; knot shape
Abstract | View details | Full text in PDF | Author Info

The shape of Scots pine (Pinus sylvestris L.) knots close to the pith of butt logs was investigated. 1,100 knots were split in a vertical direction, and their shape was measured. Knot diameter and branch angle were calculated at a distance of 40 mm from the pith of the stem. The mean diameter of all the knots in the material was 14 mm, and the branch angle 70°. Regression analysis was used to devise a formula for predicting branch angle on the basis of knot diameter. Knot size and branch angle were negatively correlated. Especially the shape of larger knots was curved. Knots achieved their maximum diameter at distance of 4–5 cm from the stem pith. The branch wood was almost completely situated above the formation point of the branch.

The PDF includes an abstract in Finnish.

  • Pietilä, E-mail: jp@mm.unknown (email)
article id 5390, category Article
Kari Heliövaara, Kari Löyttyniemi. (1989). Effect of forest fertilization on pine needle-feeding Coleoptera. Silva Fennica vol. 23 no. 4 article id 5390. https://doi.org/10.14214/sf.a15548
Keywords: Pinus sylvestris; herbivores; Chrysomelidae; Curculionidae; fertlization
Abstract | View details | Full text in PDF | Author Info

The effects of forest fertilizers on the intensity of damage caused by two curculionid (Brachyderes incanus L., Brachonyx pineti Paykull) and two chrysomelid (Calomicrus pinicola Duft., Cryptocephalus pini L.) species feeding as adults on Scots pine (Pinus sylvestris L.) needles were investigated in two pine stands growing on dry (Calluna type) sites in South-West Finland. There was much variation in the abundance of the insect species both between the trials and the sample plots. Nitrogen fertilization increased both the height and radial growth of the pines. The curculinids were slightly more abundant on the nitrogen-treated plots. Potassium application seemed to decrease the feeding intensity of the chrysomelids especially. The overall effects were so small that forest fertilization cannot be considered as an effective control method against needle-feeding beetles.

The PDF includes an abstract in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
  • Löyttyniemi, E-mail: kl@mm.unknown
article id 5389, category Article
Jyrki Tomminen, Matti Nuorteva, Markku Pulkkinen, Jouni Väkevä. (1989). Occurrence of the nematode Bursaphelenchus mucronatus Mamiya & Enda 1979 (Nematoda: Aphelenchoididae) in Finland. Silva Fennica vol. 23 no. 4 article id 5389. https://doi.org/10.14214/sf.a15547
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; Finland; wood; Bursaphelenchua xylophilus; Bursaphelenchus mucronatus; nematodes; Monochamus galloprovincialis; Monochamus sutor
Abstract | View details | Full text in PDF | Author Info

A survey was conducted in Finland in 1988 to determine whether the pine wood nematode Bursaphelenchus mucronatus Mamiya & Enda 1979 (Nematoda: Aphelenchoididae) or the closely related species B. mucronatus would occur in Finnish forests. Dead or dying standing trees and timber of two conicer species, Pinus sylvestris L. (Scots pine) and Picea abies (L.) H. Karst. (Norway spruce) were analysed for the presence of these nematodes. Monochamus spp. pine sawyers (Coleoptera: Cerambycidae) were also collected and inspected for the presence of dispersal fourth juvenile stages (dauerlarva) of the nematodes. The species B. xylophilus was not found, but B. mucronatus appeared to be widespread in the country. Individuals of this nematode were found both from Scots pine and Norway spruce. Adults of two Monochamus species were found, M. galloprovincialis and M. sutor. Only two of the examined beetles of the former species had dauerlarvae in their body.

The PDF includes an abstract in Finnish.

  • Tomminen, E-mail: jt@mm.unknown (email)
  • Nuorteva, E-mail: mn@mm.unknown
  • Pulkkinen, E-mail: mp@mm.unknown
  • Väkevä, E-mail: jv@mm.unknown
article id 5388, category Article
Martti Varmola. (1989). Männyn istutustaimikoiden lustonleveysmalli. Silva Fennica vol. 23 no. 4 article id 5388. https://doi.org/10.14214/sf.a15546
English title: A model for ring width of planted Scots pine.
Original keywords: mänty; taimikot; lustonleveys; kasvumallit; puuaineen laatu
English keywords: Pinus sylvestris; wood quality; spacing; ring width; growth models
Abstract | View details | Full text in PDF | Author Info

Ring width at breast height is presented as a function of stem radius at breast height, the ratio between the diameter of a tree and the basal area median diameter, site index, and density of stand. By means of a conversion model ring width at stump height can be estimated as a function of ring width at breast height.

According to previous studies substantially better wood quality can be expected if mean width near the pith at stump height decreases from 3 to 2 mm. According to the present study only on the poorest sites suitable for Scots pine (Pinus sylvestris L.) planting (poor Vaccinium type) the ring width is less than 3 mm at stump height even in the thickest trees. On more fertile sites a substantial increase in the recommended planting density is required, if the mean ring width is aimed to be less than 3 mm. On the best sites it is impossible to reach mean ring width of less than 2 mm, when the density is less than 4,000 stems/ha. Only the thinnest trees on the poorest sites can have a mean ring width less than 2mm.

The PDF includes an abstract in English.

  • Varmola, E-mail: mv@mm.unknown (email)
article id 5385, category Article
Timo Kuuluvainen. (1989). Branching dynamics in young Scots pine. Silva Fennica vol. 23 no. 3 article id 5385. https://doi.org/10.14214/sf.a15542
Keywords: Pinus sylvestris; biomass production; branching; tree architecture; bifuraction; modular construction; shoot demography
Abstract | View details | Full text in PDF | Author Info

The development of shoot number and shoot properties was examined in successive shoot cohorts of young widely-spaced Scots pine trees (Pinus sylvestris L.) growing in a progeny trial. This was accomplished by reconstructing the branching process of the trees over a period of five years, from tree age 4 to 8. During this time the number of shoots in successive shoot cohorts increased rapidly, while at the same time the mean shoot length decreased. The decrease in shoot lengths from older to younger shoots was accompanied by a decline in the bifuraction frequency of the shoots. In general, rapid changes occurred in the branching characteristics during the yearly development of the trees. The variation in the branching characteristics was reflected in the development of the architecture and biomass production of the trees.

The PDF includes an abstract in Finnish.

  • Kuuluvainen, E-mail: tk@mm.unknown (email)
article id 5384, category Article
Raija-Liisa Petäistö. (1989). Syyskoulinnan ajankohdan vaikutus männyn taimien kuiva-ainepitoisuuteen, neulasten pitolujuuteen ja juurten uudistumiskykyyn. Silva Fennica vol. 23 no. 3 article id 5384. https://doi.org/10.14214/sf.a15541
English title: The influence of autumn transplanting date on the dry matter content, needle retention values and root regeneration of Scots pine (Pinus sylvestris) seedlings.
Original keywords: mänty; taimitarhat; koulinta; kuiva-ainepitoisuus; juurten kasvu
English keywords: Pinus sylvestris; root growth; nurseries; transplanting; dry matter content
Abstract | View details | Full text in PDF | Author Info

The experiment was performed in 1982–85 at the forest tree nursery in Suonenjoki, Central Finland. There were four to five transplanting dates ranging from the beginning of August to the end of September. The dry matter content, root regeneration and needle retention value of Scots pine (Pinus sylvestris L.) seedlings were examined. Development of the needle retention value in autumn was followed in nurseries at Suonenjoki, Rantasalmi, Mäntyharju and Taavetti in 1982.

Root regeneration was usually the worse, the later the seedlings were transplanted in the autumn. The dry matter content was generally lowest in the seedlings transplanted later in the autumn, and also to some extent in the seedlings transplanted at the beginning of August. The needle retention value increased as autumn advanced. Early transplanting in autumn had an adverse effect on the development of needle retention, and the values were highest in the seedlings transplanted later in the autumn.

The PDF includes an abstract English.

  • Petäistö, E-mail: rp@mm.unknown (email)
article id 5382, category Article
Seppo Kellomäki, Taneli Kolström, Hannu Väisänen, Esko Valtonen. (1989). Simulations on the occurrence of dead trees in natural pine stands. Silva Fennica vol. 23 no. 3 article id 5382. https://doi.org/10.14214/sf.a15539
Keywords: Pinus sylvestris; succession; time series; mortality
Abstract | View details | Full text in PDF | Author Info

The study aimed at recognizing the phases of forest succession where dead trees most probably occur. The model simulations showed that the increasing occurrence of dead trees culminated after the canopy closure. Thereafter the occurrence of dead trees decreased representing a pattern where high frequency of dead trees was followed by low frequency of dead trees, the intervals between the peaks in the number of dead trees being in Southern Finland about 15–30 years. Around this long-term variation there was a short-term variation, the interval between the peaks in the number of dead trees being 2–4 years. This pattern was associated with the exhausting and release of resources controlled by the growth and death of trees.

The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Kolström, E-mail: tk@mm.unknown
  • Väisänen, E-mail: hv@mm.unknown
  • Valtonen, E-mail: ev@mm.unknown
article id 5379, category Article
Timo Kuuluvainen, Timo Pukkala. (1989). Effect of Scots pine seed trees on the density of ground vegetation and tree seedlings. Silva Fennica vol. 23 no. 2 article id 5379. https://doi.org/10.14214/sf.a15536
Keywords: Pinus sylvestris; natural regeneration; spatial variation; ground vegetation; seedlings; seed trees; regeneration models; ecological fields; resource consumption; competitive interface
Abstract | View details | Full text in PDF | Author Info

The study uses the methodology of ecological field theory to model the effect of Scots pine (Pinus sylvestris L.) seed trees on the density of tree seedlings and other plants in the field layer. The seed trees had a clear effect on the expected value of the amount and distribution of the ground vegetation. The vicinity of seed trees had an adverse effect on the growth of grasses, herbs and seedlings, while mosses were most abundant near the trees. Models based on the ecological field approach were derived to describe the effect of seed trees on the ground vegetation.

The PDF includes an abstract in Finnish.

  • Kuuluvainen, E-mail: tk@mm.unknown (email)
  • Pukkala, E-mail: tp@mm.unknown
article id 5378, category Article
Jukka Pietilä. (1989). Factors affecting the healing-over of pruned Scots pine knots. Silva Fennica vol. 23 no. 2 article id 5378. https://doi.org/10.14214/sf.a15535
Keywords: Pinus sylvestris; Scots pine; pruning; knots; healing-over; resin tap length
Abstract | View details | Full text in PDF | Author Info

The material of the study consisted of 21 Scots pine (Pinus sylvestris L.) trees that had been pruned in the 1930’s and 1940’s. The butt log of the pruned stems was peeled into veneer from which the length and shape of the resin taps were determined. The length of the resin tap was affected in the first place by the knot diameter and the height of the knot along the stem. The length of the resin tap was about 1.5-fold that of the knot diameter. With an increase in the height above the ground of a knot, its length decreases. The resin taps were particularly long on poor sites and in the butt end of the stems, however, the variation in tap length was large both within and between the individual tree stands. The shape of the resin taps is presented in this study by diameter classes. The resin taps studied in the work were longer than those measured in other works. This may be due to the fact that the knots were uncovered by peeling instead of sawing.

The PDF includes an abstract in Finnish.

  • Pietilä, E-mail: jp@mm.unknown (email)
article id 5376, category Article
Timo Pukkala. (1989). Predicting diameter growth in even-aged Scots pine stands with a spatial and non-spatial model. Silva Fennica vol. 23 no. 2 article id 5376. https://doi.org/10.14214/sf.a15533
Keywords: Pinus sylvestris; growth prediction; spatial distribution; growth models; tree models
Abstract | View details | Full text in PDF | Author Info

The single tree growth models presented in this study were based on about 4,000 trees measured in 50 even-aged Scots pine (Pinus sylvestris L.) sample plots with varying density, spatial pattern of trees and stand age. Predictors that used information about tree locations decreased the relative standard error of estimate by 10 percentage points (15%), if past growth was not used as a predictor, and about 15 percentage points (30%) when past growth was one of the predictors. When ranked according to the degree of determination, the best growth models were obtained for the basal area increment, the next best for relative growth, and the poorest for diameter increment. The past growth decreased the relative standard error of estimate by 15–20 percentage points, but did not make the spatial predictors unnecessary. The degree of determination of the spatial basal area growth model was almost 80% if the past growth was unknown and almost 90% if the past growth was known. Variables that described the amount of removed competition did not improve the growth models.

The PDF includes an abstract in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5375, category Article
Timo Pukkala. (1989). Prediction of tree diameter and height in a Scots pine stand as a function of the spatial pattern of trees. Silva Fennica vol. 23 no. 2 article id 5375. https://doi.org/10.14214/sf.a15532
Keywords: Pinus sylvestris; diameter distribution; competition; spatial distribution; simulations studies; tree models
Abstract | View details | Full text in PDF | Author Info

The study presents two methods of predicting tree dimensions in a Scots pine (Pinus sylvestris L.) stand if only the location of trees is known. The first method predicts the tree diameter from the spatial location of neighbours. In the second method the diameter distribution of a subarea is estimated from the local stand density. This distribution is then sampled to obtain diameters. In both methods the tree height is predicted with a spatial model on the basis of diameters and locations of trees. The main purpose of the presented models is to generate realistic stands for simulation studies.

The PDF includes an abstract in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5371, category Article
Riitta Laurila. (1989). Pieniläpimittaisen männyn kuituominaisuudet. Silva Fennica vol. 23 no. 1 article id 5371. https://doi.org/10.14214/sf.a15530
English title: Fibre properties in Pinus sylvestris pulpwood.
Original keywords: kuitupuu; pienpuu; mänty; trakeidit; puuaineen ominaisuudet; kuitujen pituus; soluseinän paksuus
English keywords: Pinus sylvestris; cell wall thickness; wood properties; pulpwood; small-sized stems; tracheid length; smallwood
Abstract | View details | Full text in PDF | Author Info

Properties of fibres in pulpwood, especially length, width and the thickness of walls in tracheids, are essential for strength properties of pulp and paper. Length and width of tracheids increase from pith to surface in radial direction. Young and small-sized stems have also smaller fibres. Small-sized Pinus sylvestris L. test trees had tracheids that were shorter both in stems and knot wood than those in normal sized trees. However, cell walls in test trees were as thick as in normal sized trees. It seems that especially the L/T -ratio (length/thickness) in small stems is worse than in normal sized pulp wood.

The PDF includes an abstract in English.

  • Laurila, E-mail: rl@mm.unknown (email)
article id 5368, category Article
Kari Heliövaara, Rauno Väisänen. (1989). Invertebrates of young Scots pine stands near the industrial town of Harjavalta, Finland. Silva Fennica vol. 23 no. 1 article id 5368. https://doi.org/10.14214/sf.a15527
Keywords: Pinus sylvestris; Finland; Harjavalta; mites; air pollution; invertebrates; aphids; Arthropoda
Abstract | View details | Full text in PDF | Author Info

Invertebrates of young Scots pine (Pinus sylvestris L.) stands were preliminarily studied along a gradient of industrial air pollutants in Harjavalta, south-western Finland. Bark samples and net samples on pine branches and needles were taken in May–June, 1987. The number of aphids on needles was highest near the industrial plants. The number of mites in bark was positively correlated with the increasing distance from the pollutant source. Detrended correspondence analysis ordination calculated according to the bark invertebrates showed that the sampling sites of the zones far from the emission source formed a distinct group while those of the zones near the source were relatively widely dispersed indicating disturbances in faunal structure.

The PDF includes an abstract in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
  • Väisänen, E-mail: rv@mm.unknown
article id 5367, category Article
Kari Heliövaara, Rauno Väisänen. (1989). Quantitative variation in the elemental composition of Scots pine needles along a pollutant gradient. Silva Fennica vol. 23 no. 1 article id 5367. https://doi.org/10.14214/sf.a15526
Keywords: Pinus sylvestris; needles; Finland; nutrients; Harjavalta; air pollution; heavy metals; herbivores
Abstract | View details | Full text in PDF | Author Info

Quantitative variation in the elemental composition of living Scots pine needles was studied along an atmospheric pollutant gradient in the surroundings of the industrial town Harjavalta, south-western Finland. Two 9-km-long transects, each with nine sample plots, running to the S and SW from factory complex were delimited in a homogenous Scots pine (Pinus sylvestris L.) forest. Needle samples were taken from 10 trees at each site, and from two separate sites in Tuusula near Helsinki. There was considerable spatial variation in the elemental composition of the needles. Heavy metals (Cu, Fe, Zn) showed a clear pattern of exponentially decreasing concentration with increasing distance from the emission source. Sodium and potassium concentrations, as well as the ash weight and air-dry weight, also decreased. Magnesium, manganese and calcium concentrations increased with increasing distance.

The PDF includes an abstract in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
  • Väisänen, E-mail: rv@mm.unknown
article id 5364, category Article
Urban Bergsten. (1988). Invigoration and IDS-sedimentation of Pinus sylvestris seeds from northern Finland. Silva Fennica vol. 22 no. 4 article id 5364. https://doi.org/10.14214/sf.a15521
Keywords: Pinus sylvestris; germination; Scots pine; northern Finland; seed quality; elimination of non-productive seeds; invigoration of seeds
Abstract | View details | Full text in PDF | Author Info

In Northern Finland as well as in Northern Sweden there is a shortage of high-quality Scots pine (Pinus sylvestris L.) seeds, mostly due to unsuitable temperatures during the development and maturation of cones and seeds. Methods have been developed for elimination of non-productive seeds and for invigoration of seeds. In the present work, these methods were tested on poorly developed seed lot from Rovaniemi, Northern Finland (66°15’–66°30’; 180 m a.s.l.). The seeds were conditioned using the following treatments:

1. PREVAC method (5 min, 97 kPa below atmospheric pressures) for removal of mechanically damaged seeds (7%)

2. Invigoration using incubation at controlled moisture content (30% f.w) and continuous air supply, for 14 days at 5°C.

3. Additional water supply for 16 hours at 5°C.

4. Drying in dehumidified air until a near maximum difference in density between viable and dead seeds was obtained

5. Separation in a sedimentation flume to achieve a gradient of fractions of different germination rate and capacity.

The treatments resulted in an improvement of germination percentage from 33 to about 95% and a reduction in mean germination time from 8.8 days to 6 days if the control and the best fractions (32% seeds) were compared.

  • Bergsten, E-mail: ub@mm.unknown (email)
article id 5361, category Article
Kari Heliövaara, Rauno Väisänen. (1988). Interactions among herbivores in three polluted pine stands. Silva Fennica vol. 22 no. 4 article id 5361. https://doi.org/10.14214/sf.a15518
Keywords: Pinus sylvestris; Scots pine; Finland; Harjavalta; air pollution; insect pests; herbivores
Abstract | View details | Full text in PDF | Author Info

Succession of insect attacks on young Scots pine (Pinus sylvestris L.) was studied in heavily, moderately and slightly polluted pine stands within a three-kilometre distance from a prominent emission source in Western Finland. The total number of pest species was highest in the moderately polluted stand, but unlike other herbivores, aphids were also abundant in the heavily polluted stands. A few positive but no negative interactions were detected between herbivores, which suggests that insect species may benefit from a previous occurrence of other species in the same tree.

The PDF includes an abstract in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
  • Väisänen, E-mail: rv@mm.unknown
article id 5357, category Article
Heikki Hänninen, Paavo Pelkonen. (1988). Effects of temperature on dormancy release in Norway spruce and Scots pine seedlings. Silva Fennica vol. 22 no. 3 article id 5357. https://doi.org/10.14214/sf.a15514
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; bud burst; dormancy release; annual cycle of development; chilling requirement; rest period; simulation model
Abstract | View details | Full text in PDF | Author Info

Models concerning the effects of temperature on dormancy release in woody plants were tested using two-year old seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.). Chilling experiments suggest that the rest period has a distinct end point. Before the attainment of this end point high temperatures do not promote bud development towards dormancy release, and after it further chilling does not affect the subsequent bud development. A new hypothesis of dormancy release is suggested on the basis of a comparison between present and earlier findings. No difference in the proportion of growth commencing seedlings were detected between the forcing temperatures of 17°C and 22°C. The rest break of 50% of Norway spruce and Scots pine seedlings required six and eight weeks of chilling, respectively. Great variation in the chilling requirement was found, especially for Scots pine.

The PDF includes an abstract in Finnish.

  • Hänninen, E-mail: hh@mm.unknown (email)
  • Pelkonen, E-mail: pp@mm.unknown
article id 5356, category Article
Pekka Lähdesmäki, Pekka Pietiläinen. (1988). Seasonal variation in the nitrogen metabolism of young Scots pine. Silva Fennica vol. 22 no. 3 article id 5356. https://doi.org/10.14214/sf.a15513
Keywords: Pinus sylvestris; winter dormancy; amino acids; arginine; proteins; nitrate reductase; γ-glutamyltransferase; pine buds and needles; nitrogen metabolism
Abstract | View details | Full text in PDF | Author Info

Seasonal changed in total nitrogen, protein, amino acid, ammonia, nitrate and nitrite concentrations, and nitrate reductase and γ-glutamyltransferase activities in the needles, buds and shoots of young Scots pine (Pinus sylvestris L.) were studied. A relationship between the variation in the nitrogen metabolism and both winter dormancy and its breaking was proposed. Pine tissues stored soluble nitrogen over the winter largely in the form of arginine which, in addition to a high nitrogen content, can neutralize acidic cytoplasmic constituents such as nitrates and nitrites. Specific nitrate reductase and γ-glutamyltransferase activities were highest in late summer or autumn, and is apparently connected to the mobilization of nitrogen reserves for the winter.

The PDF includes an abstract in Finnish.

  • Lähdesmäki, E-mail: pl@mm.unknown (email)
  • Pietiläinen, E-mail: pp@mm.unknown
article id 5354, category Article
Jan-Erik Nilsson. (1988). Variation in the rate of winter hardening of one-year-old plus-tree families of Scots pine raised in different enviroments. Silva Fennica vol. 22 no. 3 article id 5354. https://doi.org/10.14214/sf.a15511
Keywords: Pinus sylvestris; selection; breeding; seed orchards; cold acclimation; cold tolerance; full-sib families
Abstract | View details | Full text in PDF | Author Info

The effect of different environmental conditions (four outdoor localities and one greenhouse locality in Northern Sweden) on cold hardening of 29 one-year-old full-sib families from plus-trees of Scots pine (Pinus sylvestris L.) were studied by artificial freeze testing. Plants exposed to low night temperatures during August achieved faster cold hardening than plants raised in milder localities. The family ranking for rate of winter hardening was consistent among outdoor localities if freeze testing was performed at times when plants from different localities had attained similar levels of cold hardiness. However, significant family x locality interactions were obtained when plants from the outdoor localities were freeze tested on the same occasion. Freeze damage was positively correlated with plant height but not correlated with dry matter content in the autumn. Freezing damage of greenhouse raised plus-tree families was uncorrelated with damage of plants raised outdoors. Possible implications for hardiness breeding are suggested.

The PDF includes an abstract in Finnish.

  • Nilsson, E-mail: jn@mm.unknown (email)
article id 5352, category Article
Lars Christersson, Heinrich A. von Fircks. (1988). Injuries to conifer seedlings caused by simulated summer frost and winter desiccation. Silva Fennica vol. 22 no. 3 article id 5352. https://doi.org/10.14214/sf.a15509
Keywords: Pinus sylvestris; Picea abies; Picea mariana; conifers; frost damage; Sweden; Pinus contorta; seedlings; cold tolerance; frost hardiness in growing phase; winter desiccation
Abstract | View details | Full text in PDF | Author Info

Visible frost damage to forest trees in Sweden seldom occurs in winter but is frequent in late spring, summer and early autumn. Frosts are frequent in all seasons in various parts of Sweden, even in the southernmost part (lat. 56°, N) and temperatures may be as low as -10°C even around mid-summer. Ice crystal formation within the tissues, which in most seedlings takes place at around -2°C, causes injury, not the sub-zero temperatures themselves.

The apical meristem, the elongated zone, and the needles of seedlings of Picea abies (L.) H. Karst. in a growing phase were damaged at about -3°C and those of Pinus sylvestris L. at about -6°C. Other species of the genus Pinus were tested and most were found to be damaged at about -6°C, with some variations. Picea species tested were damaged at about -3°C to -4°C.

A method has been designed to compare the response of different species to winter desiccation, which occurs under conditions of (1) low night temperature, (2) very high irradiation and increase in needle temperature during the photoperiod, (3) frozen soil, and (4) low wind speed. There were differences in response to winter desiccation between pine and spruce species. Seedlings of Pinus contorta tolerated these winter desiccation conditions much better than those of P. sylvestris or Picea abies. Picea mariana was the least tolerant of the species tested.

The PDF includes an abstract in Finnish.

  • Christersson, E-mail: lc@mm.unknown (email)
  • Fircks, E-mail: hf@mm.unknown
article id 5347, category Article
Timo Kuuluvainen, Markku Kanninen, Juha-Pekka Salmi. (1988). Tree architecture in young Scots pine: properties, spatial distribution and relationships of components of tree architecture. Silva Fennica vol. 22 no. 2 article id 5347. https://doi.org/10.14214/sf.a15504
Keywords: Pinus sylvestris; crown architecture; biomass production; branching pattern; tree ideotype
Abstract | View details | Full text in PDF | Author Info

The architecture of Scots pine (Pinus sylvestris L.) was studied in an eight-year-old progeny test. The measurements included characteristics of crown structure, spatial distribution of shoots and yield components. The spatial distribution of shoots showed striking between-tree differences, and two extreme distribution patterns were detected. One represented a non-layered structure with a vertically relative even shoot distribution, and the other a layered structure with a vertically highly uneven shoot distribution.

Close correlations existed between several components of tree architecture and it is suggested that changes in the phenotypic architecture in Scots pine follow an epigenetic pattern, which enables the prediction of adaptational changes in structural components. The structural characteristics related to high above-ground biomass were a long crown, high total shoot length, high number of branches per whorl and big shoots of low needle density occupying a big share of the crown volume.

The PDF includes a summary in Finnish.

  • Kuuluvainen, E-mail: tk@mm.unknown (email)
  • Kanninen, E-mail: mk@mm.unknown
  • Salmi, E-mail: js@mm.unknown
article id 5338, category Article
Timo Pukkala. (1988). Effect of spatial distribution of trees on the volume increment of a young Scots pine stand. Silva Fennica vol. 22 no. 1 article id 5338. https://doi.org/10.14214/sf.a15495
Keywords: Pinus sylvestris; simulation; competition; spatial distribution; growth model; spatial pattern
Abstract | View details | Full text in PDF | Author Info

The effect of grouping on 5-year old volume increment was studied by a simulation technique using spatial growth models estimated in Scots pine (Pinus sylvestris L.) stands in the phase of the first commercial thinning. A total of 24 model stands were regenerated by applying 12 spatial processes for two different diameter distributions. In addition to model stands, 6 different thinnings were simulated in two real stands. The clustering of trees was described with Fisher’s grouping index and by estimating the relative interception of diffuse radiation. In model stands with constant diameter distribution the correlation between the grouping index and volume increment ranged from -0.81 to -0.91. The correlation between volume increment and interception was 0.81–0.83 with one diameter distribution and 0.70 if both distributions were combined. In one thinned stand the correlation between the growth estimate and grouping index varied between -0.33 and 0.76. The correlation between interception and growth was about 0.30 in one stand and 0.72 if both stands were combined. Small irregularities do not decrease the volume production of a young Scots pine stand, but if the clustering is considerable or there are reasonably wide harvest strips, growth will be reduced by 10–20%.

The PDF includes a summary in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5318, category Article
Tapio Lindholm, Harri Vasander. (1987). Vegetation and stand development of mesic forest after prescribed burning. Silva Fennica vol. 21 no. 3 article id 5318. https://doi.org/10.14214/sf.a15475
Keywords: Pinus sylvestris; succession; forest types; Myrtillus type; controlled burning; prescibed burning; boreal zone
Abstract | View details | Full text in PDF | Author Info

This study deals with the succession of vegetation and tree stand in 16 mesic Myrtillus site type Scots pine (Pinus sylvestris L.) plantations after prescribed burning in Evo, Southern Finland. The oldest tree stands studied were about 30-year-old. The growth of trees followed the height index of Myrtillus type. The vegetation was first mesic, dominated by grasses and herbs, turning more xeric after four years. This change was accelerated by treatment with herbicides. After the closure of tree stand, vegetation became more characteristic of forest vegetation, but pioneer species and composition disappeared slowly. The basic characters of vegetation succession could be clearly described by DCA ordination and TWINSPAN classification. The study confirmed that Myrtillus type has succession phases which are typical for each age phases as Cajander’s forest site type theory has proposed. However, differences in primary and secondary site factors have their own effects on the vegetation of the succession phases.

The PDF includes an abstract in Finnish.

  • Lindholm, E-mail: tl@mm.unknown (email)
  • Vasander, E-mail: hv@mm.unknown
article id 5315, category Article
Seppo Kellomäki, Matti Seppälä. (1987). Simulations on the effects of timber harvesting and forest management on the nutrient cycle and productivity of Scots pine stands. Silva Fennica vol. 21 no. 2 article id 5315. https://doi.org/10.14214/sf.a15472
Keywords: Pinus sylvestris; forest management; productivity; fertilization; nitrogen; simulation; rotation; timber harvest; nitrogen cycle
Abstract | View details | Full text in PDF | Author Info

Effects of varying rotation, thinning, fertilization and harvest intensity on the productivity and nitrogen cycle of Scots pine (Pinus sylvestris L.) stand were studied on the basis of computer simulation. The increasing intensity of management increased the loss of nitrogen in the cycle. Short rotation, associated with early thinning by means of the whole tree harvest, proved to be especially detrimental regarding the productivity of the forest ecosystem. Fertilization associated with thinnings is of great importance in maintaining the productivity of a forest ecosystem during an intensive timber harvest.

The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Seppälä, E-mail: ms@mm.unknown
article id 5312, category Article
Timo Pukkala. (1987). Siementuotannon vaikutus kuusen ja männyn vuotuiseen kasvuun. Silva Fennica vol. 21 no. 2 article id 5312. https://doi.org/10.14214/sf.a15469
English title: Effect of seed production on the annual growth of Picea abies and Pinus sylvestris.
Original keywords: kuusi; mänty; Lappi; siemensato; sädekasvu; kesäpuu
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; Finland; latewood; Lapland; radial growth; seed crop
Abstract | View details | Full text in PDF | Author Info

The study material consisted of 13 rather old Norway spruce (Picea abies (L.) H. Karst.) and 17 Scots pine (Pinus sylvestris L.) stands located in different parts of Finland. In each stand the seed crops, radial growth and amount of latewood were measured during a period of about ten years. Seed production reduces the radial growth of spruce and pine in the year of seed maturing. In Southern and Central Finland also the proportion of latewood is reduced. Seed production accounts for about 14% of the variation in radial growth of a spruce stand growing in Lapland, and 27% in other parts of Finland. In pine stands the seed crop explains 19% of the variation in radial growth in Lapland, and only 7% in the rest of Finland. In spruce stands an average seed crop reduces radial growth by 14% in Lapland and 5% in the rest of the country. An abundant seed production causes a reduction of about 20%. In southern parts of Finland, the proportion of latewood is reduced by 5% in an average seed year and by 24% in a good seed year. In pine stands an average seed crop decreases the width of annual ring by 5%, and a good seed crop by 15%. Outside Lapland, also the proportion of latewood is reduced: in an average seed year by 5%, and in a good seed year by 16%. The reduction in volume growth of spruce stands due to an average seed crop was estimated to be about 10% in Lapland, and 6% in other parts of Finland. A prolific seed production causes a reduction of 20%. In old pine stands the reduction is 5% in an average seed year, and 15% in a good seed year.

The PDF includes an abstract in English.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5311, category Article
Timo Pukkala. (1987). Kuusen ja männyn siemensadon ennustemalli. Silva Fennica vol. 21 no. 2 article id 5311. https://doi.org/10.14214/sf.a15468
English title: Model for predicting the seed crop of Picea abies and Pinus sylvestris.
Original keywords: kuusi; mänty; luontainen uudistaminen; Lappi; siemensato; lämpötila; kukinnan aloitus; ennustemalli
English keywords: Pinus sylvestris; Norway spruce; Picea abies; natural regeneration; Scots pine; Finland; Lapland; predictive modelling; seed crop; flowering initiation; influence of temperature
Abstract | View details | Full text in PDF | Author Info

The seed crop of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) is predicted with the help of mean monthly temperatures during May–August one and two years before the flowering year. The prediction models were made separately for Lapland and for the rest of Finland. The models are based on 10-year periods of seed crop measurements and climatic data. The total number of time series was 59.

In Lapland, Norway spruce flowered abundantly and produced an abundant seed crop after warm July–August and two years after cool July–August. In other parts of Finland, warm June and July produced a good flowering year, especially if these months were cool two years before the flowering year.

In Lapland, Scots pine flowered abundantly if the whole previous growing season was warm. Elsewhere in Finland, a cool June preceded prolific flowering in the coming year if the rest of the growing season was considerably warmer than the average.

The prediction models explained 37–49 % of the variation in the size of the seed crop. The occurrence of good and poor seed years was usually predicted correctly. Using the presented models, the prediction of the seed crop is obtainable 1.5 year for Norway spruce and 2.5 year for Scots pine before the year of seed fall.

The PDF includes an abstract in English.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5310, category Article
Petri Kärenlampi. (1987). Puun lahonkestävyys ja kosteusdynamiikka. Silva Fennica vol. 21 no. 2 article id 5310. https://doi.org/10.14214/sf.a15467
English title: The decay resistance and moisture dynamics of wood.
Original keywords: puulajit; kosteus; sydänpuu; puuaines; lahonkestävyys; mantopuu
English keywords: Pinus sylvestris; Picea abies; sapwood; tree species; heartwood; decay resistance; moisture
Abstract | View details | Full text in PDF | Author Info

In laboratory studies the heartwood content seems to be the only natural property of a wood of different tree species influencing the decay resistance. Moistening and drying by diffusion happen quite slowly. Scots pine (Pinus sylvestris L.) sapwood takes moisture by capillary action quicker than pine heartwood and Norway spruce (Picea abies (L.) H. Karst.) wood. Swelling and shrinkage are also greatest in pine sapwood. Impregnation of pine sapwood can give it better hydrophobic and dimensional stability than that of pine heartwood.

The PDF includes an abstract in English.

  • Kärenlampi, E-mail: pk@mm.unknown (email)
article id 5306, category Article
Timo Pukkala, Taneli Kolström. (1987). Competition indices and the prediction of radial growth in Scots pine. Silva Fennica vol. 21 no. 1 article id 5306. https://doi.org/10.14214/sf.a15463
Keywords: Pinus sylvestris; stand characteristics; simulation; tree growth; competition; radial growth
Abstract | View details | Full text in PDF | Author Info

The effect of competition on the radial growth of Scots pine (Pinus sylvestris L.) was studied in three naturally regenerated stands located in North Karelia, Finland. The competition situation of an individual tree was described with various competition indices which depended on the sizes and distances from the neighbouring trees. One competition index explained about 50% of the variation in 5-year radial growth in one stand. If all stands were combined, one index explained 43.5%, two indices 48.9% and three indices 51.2% of the variation. In one stand, the best competition indices accounted for about 20% of that variation which could not be explained by tree diameter. If all three stands were combined, the best index explained 11% of the residual variation. About 40% of the variation in 5-year radial growth could not be explained by the diameter and competition indices.
The PDF includes an abstract in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
  • Kolström, E-mail: tk@mm.unknown
article id 5305, category Article
Timo Pukkala. (1987). Simulation model for natural regeneration of Pinus sylvestris, Picea abies, Betula pendula and Betula pubescens. Silva Fennica vol. 21 no. 1 article id 5305. https://doi.org/10.14214/sf.a15462
Keywords: Pinus sylvestris; Betula pendula; Picea abies; germination; Betula pubescens; mortality; seed crop; computer model; stochastic simulation; birth model
Abstract | View details | Full text in PDF | Author Info

In the model the regeneration process is derived into three subprocesses: birth, growth and mortality of seedlings. The main emphasis is on the birth process where the following phases are simulated: seed crop, quality of seeds, maturity of seeds, predation of seeds and germination. The parameters are based on data published in Finland. Part of the parameters are obtained directly from the investigations and part is proposed by the author. The model can be calibrated by changing parameter values. The simulation is made with the help of random numbers which have the same means as the estimates and the same distributions as the residuals of the equations used in simulation. The time step of the model is one year. The number of emerged seedlings in one year is obtained by multiplying the seed crop with the probabilities that the seed passes different phases of the birth process. Because of stochasticity the regeneration period is simulated several times. From the results it is possible to evaluate the risk and succeeding probability of the regeneration. The main drawbacks of the simulation method are the lack of empirical parameters and the difficulty of testing. The model could be further developed by including spatiality into the model.

The PDF includes an abstract in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5303, category Article
Hannu Raitio. (1987). Neulasvuosikertojen merkitys neulasanalyysin tulkinnassa. Silva Fennica vol. 21 no. 1 article id 5303. https://doi.org/10.14214/sf.a15460
English title: The significance of the number of needle year classes of Scots pine in interpreting needle analysis results.
Original keywords: mänty; ravinnepitoisuus; neulasvuosikerta; neulasanalyysi
English keywords: Pinus sylvestris; nitrogen; Scots pine; phosphorus; needle analysis; potassium; magnesium; needle year classes
Abstract | View details | Full text in PDF | Author Info

This study deals with significance of the number of needle year classes in estimating the nitrogen, phosphorus, potassium and magnesium status of Scots pine (Pinus sylvestris L.) plants on the basis of needle analysis. Due to the nutrient retranslocation deficiencies in these nutrients are best determined by analysing separately the needles of the topmost branch whorls possessing one, two or three needle year classes. The concentrations of those nutrients which are not scarce will then increase as needle year classes decrease. In cases of deficiency, on the other hand, the content of the nutrient concerned will remain the same or decrease. Only severe deficiencies are revealed by the examination of the nutrient concentrations of only the youngest or the oldest needles.

The PDF includes an abstract in English.

  • Raitio, E-mail: hr@mm.unknown (email)
article id 5302, category Article
Seppo Kellomäki, Heikki Hänninen, Taneli Kolström, Ahti Kotisaari, Timo Pukkala. (1987). A tentative model for describing the effects of some regenerative process on the properties of natural seedling stands. Silva Fennica vol. 21 no. 1 article id 5302. https://doi.org/10.14214/sf.a15459
Keywords: Pinus sylvestris; natural regeneration; Scots pine; modelling; stand density; seed crop; seed dispersal; parent tree
Abstract | View details | Full text in PDF | Author Info

The effect of the size of seed crop, dispersal of seeds and the early development of seedlings on the density and spatial distribution of young Scots pine (Pinus sylvestris L.) stands are evaluated on the basis of theoretical models. The models include (i) number and spatial distribution of parent trees on the regeneration area, (ii) size of annual seed crop, (iii) seed dispersal from a particular parent tree, (iv) germination of the seeds (germination percentage), (v) death of ageing seedlings after the establishment process, and (vi) height growth of the seedlings.

As expected, stand density and spatial distribution varied within a large range in relation to the density of the parent trees and the distance from them. The simulations also showed that natural seedling stands can be expected to be heterogenous due to the geometry of seed dispersal, emphasizing the frequency of young and small trees. The properties of the seedling stands were, however, greatly dependent on the density of the parent trees and the length of the regeneration period.

The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Hänninen, E-mail: hh@mm.unknown
  • Kolström, E-mail: tk@mm.unknown
  • Kotisaari, E-mail: ak@mm.unknown
  • Pukkala, E-mail: tp@mm.unknown
article id 5276, category Article
Kari Heliövaara, Rauno Väisänen. (1986). Parasitization in Petrova resinella (Lepidoptera, Tortricidae) galls in relation to industrial air pollutants. Silva Fennica vol. 20 no. 3 article id 5276. https://doi.org/10.14214/sf.a15455
Keywords: Pinus sylvestris; Scots pine; insect damages; air pollution; Petrova resinella; gall stage; parasites
Abstract | View details | Full text in PDF | Author Info

Paratization of Petrova resinella L. in the gall stage was studied in the surrounding of Harjavalta, south-western Finland, in relation to industrial air pollution. Of the studied 283 galls, 28% produced a moth, 52% of the larvae/pupae were paratisized, and 20% were empty or contained a dead larva. The proportion of paratisized galls did not depend on the distance from emission sources of industrial air pollutants.

The PDF includes an abstract in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
  • Väisänen, E-mail: rv@mm.unknown
article id 5275, category Article
Pirkko Velling, Gérard Nepveu. (1986). Männyn puuaineen laadun ja tuotoksen vaihtelu suomalaisessa provenienssikoesarjassa. Silva Fennica vol. 20 no. 3 article id 5275. https://doi.org/10.14214/sf.a15454
English title: Variation of wood quality and yield in a Finnish series of provenance trials on Scots pine.
Original keywords: mänty; kasvupaikka; alkuperä; puuaineen tiheys; maantieteellinen vaihtelu; kuitusaanto
English keywords: Pinus sylvestris; Scots pine; wood density; geographical variation; increment cores; fibre yield
Abstract | View details | Full text in PDF | Author Info

The purpose of the study was to determine the effects of the origin of seeds and the location of cultivation of Scots pine (Pinus sylvestris L.) on certain properties particularly important to the pulp industry. The research material consisted of six parallel trials of the same 12 provenances. Increment cores were taken of a total of 1,267 sample trees, 19 years old. The location of the trial site generally affected the properties to a larger extent than the origin of the seed. The effect of the variation of wood density and fibre yield on the cultivation values of the provenances was only a few percentages on average, however, at most the effect was nearly 10%. Eastern Finnish provenances adapted well to western Finnish conditions.

The PDF includes an abstract in Finnish and French.

  • Velling, E-mail: pv@mm.unknown (email)
  • Nepveu, E-mail: gn@mm.unknown
article id 5274, category Article
Pertti Hari, Pirkko Heikinheimo, Leo Kaipiainen, Eeva Korpilahti, Annikki Mäkelä, Juha Samela. (1986). Trees as a water transport system. Silva Fennica vol. 20 no. 3 article id 5274. https://doi.org/10.14214/sf.a15453
Keywords: Pinus sylvestris; branches; stem; water transport system; cross-sectional-area; coarse roots
Abstract | View details | Full text in PDF | Author Info

The structure of 20 Scots pine (Pinus sylvestris L.) trees was analysed as a water transport system. There is a tight linear regression between the cross-sectional area of the stem at the height of its lowest living branch and the cross-sectional area of its coarse roots, between the cross-sectional area of the stem at the height of its lowest living branch and the total cross-sectional area of its branches, and between the cross-sectional area of the base of a branch and the total cross-sectional area of subsidiary branches of that branch. The capacity of successive organs, measured as cross-sectional areas, to transport water was thus found to be regular within a tree.

The PDF includes an abstract in Finnish.

  • Hari, E-mail: ph@mm.unknown (email)
  • Heikinheimo, E-mail: ph@mm.unknown
  • Kaipiainen, E-mail: lk@mm.unknown
  • Korpilahti, E-mail: eeva.korpilahti@luke.fi
  • Mäkelä, E-mail: am@mm.unknown
  • Samela, E-mail: js@mm.unknown
article id 5270, category Article
Pekka Kilkki, Risto Päivinen. (1986). Weibull function in the estimation of the basal area dbh-distribution. Silva Fennica vol. 20 no. 2 article id 5270. https://doi.org/10.14214/sf.a15449
Keywords: Pinus sylvestris; diameter distribution; beta function; nonlinear regression; maximum likelihood; initial parameter estimates; relascope sample plot
Abstract | View details | Full text in PDF | Author Info

The paper demonstrates the possibility of using data from small relascope sample plots in the derivation of the regression models which predict the Weibull function parameters for the dbh-distribution. The Weibull parameters describing the basal area dbh-distribution were estimated for relascope sample plots from the Finnish National Forest Inventory. In the first stage of the estimation nonlinear regression analysis was employed to derive initial parameter estimates for the second stage, in which the maximum likelihood method was used. The parameter estimates were employed as dependent variables for the derivation of the regression models; the independent variables comprised of the compartment-wise stand variables generally estimated in ocular inventories.

The PDF includes an abstract in Finnish.

  • Kilkki, E-mail: pk@mm.unknown (email)
  • Päivinen, E-mail: rp@mm.unknown
article id 5267, category Article
Matti Kärkkäinen. (1986). Mänty- ja kuusirunkojen arvosuhteet. Silva Fennica vol. 20 no. 2 article id 5267. https://doi.org/10.14214/sf.a15446
English title: Value relations of Scots pine and Norway spruce stems.
Original keywords: kuusi; paperiteollisuus; mänty; sahatavara; sahateollisuus; raaka-aine; rungon koko
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; simulation; pulping; sawn goods; sawmill industry; pulp industry; raw material; stem size
Abstract | View details | Full text in PDF | Author Info

A mathematical model was developed for determining the value of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) stems on the basis of sawing and pulping. The model was based on selling prices of sawn goods, pulp and other products as well as processing costs. Sawing was applied to large-dimension parts of stems and pulping to other parts and small stems. Bark and other residues were burned. The quality of pine stems was described by the distance of the lowest dead branch. In spruce only stem size affected the quality-

According to the results, the size of stem affects considerably the value of pine stems and clearly that of spruce stems. The main reason is an increase in the productivity of frame sawing as the stem size increases. In pine another factor is the higher price of sawn goods. The effect of pulp price increases as the stem size decreases. Even in large sized stems the effect of pulp was notable as the value of chips and saw dust was determined on the basis of product values in export. The competition ability of mechanical pulp was greatly affected by the price of electricity.

The PDF includes an abstract in English.

  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 5266, category Article
Matti Kärkkäinen. (1986). Malli männyn, kuusen ja koivun puuaineen oksaisuudesta. Silva Fennica vol. 20 no. 2 article id 5266. https://doi.org/10.14214/sf.a15445
English title: Model of knottiness of wood material in pine, spruce and birch.
Original keywords: kuusi; mänty; oksaisuus; rauduskoivu; hieskoivu; simulointi; aihion poikkileikkaus; puutavaran laatu
English keywords: Pinus sylvestris; Norway spruce; birch; Betula; Picea abies; Scots pine; simulation; knots; timber quality; knottiness
Abstract | View details | Full text in PDF | Author Info

A computer model was developed for predicting knottiness of wood material of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) and birch (Betula sp). The prediction included location of knots, their size and quality, i.e. if they are dead or living knots. The model suits best for tree species where branches are born at the base of shoots, in Finland such tree species is Scots pine.

The usefulness of the model was tested in the prediction of knots in wooden elements of joinery industry. According to the results, the shape of cross section affects the surface quality of elements. Especially useful is a quadratic cross section as it increases the probability to get a knotless surface.

The PDF includes an abstract in English.

  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 5265, category Article
J. Ross, S. Kellomäki, P. Oker-Blom, V. Ross, L. Vilikainen. (1986). Architecture of Scots pine crown. Silva Fennica vol. 20 no. 2 article id 5265. https://doi.org/10.14214/sf.a15444
Keywords: Pinus sylvestris; Scots pine; needle dimensions; shoot structure; phytometrical regressions
Abstract | View details | Full text in PDF | Author Info

Dimensions (length, width and thickness) of needles in crowns of young Scots pine (Pinus sylvestris L.) were found to be related linearly to each other. Similarly, the needle area was linearly correlated with the needle biomass. In the lower crown, needle length was linearly correlated with the length of the shoot, but in the upper crown needle length did not vary according to any regular pattern. Needle density was negatively correlated with shoot length. In the lower crown the needle density varied 20–40 cm-1 and in the upper crown 15– 20 cm-1. The increasing angle of aging needles seemed to be characteristic for Scots pine shoots.

The PDF includes an abstract in Finnish.

  • Ross, E-mail: jr@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Oker-Blom, E-mail: po@mm.unknown
  • Ross, E-mail: vr@mm.unknown
  • Vilikainen, E-mail: lv@mm.unknown
article id 5264, category Article
Kari Heliövaara. (1986). Occurrence of Petrova resinella (Lepidoptera, Tortricidae) in a gradient of industrial air pollutants. Silva Fennica vol. 20 no. 2 article id 5264. https://doi.org/10.14214/sf.a15443
Keywords: Pinus sylvestris; Harjavalta; insect damages; air pollution; Petrova resinella; galls
Abstract | View details | Full text in PDF | Author Info

The relationship between industrial air pollutants and the occurrence of galls of Petrova resinella (Lepidoptera, Torticiadae) was studied around the industrialized town of Harjavalta in Western Finland. There were 44 sampling sites set out at logarithmic distances along five transects (NW, W, SW, SE) froma a distive source of emissions. Each site consisted of three circular sample plots (30 m2) in young Scots pine (Pinus sylvestris L.) stands. The number of galls, including cankers from several years earlier, was highest in the vicinity of the factory complex on each transect. The highest number of two-year-old galls containing living larvae was usually recorded at the ends of the transects several kilometres from the factories. However, the significance of the differences both between zones and transects was rather low. Correlations between the deposition of heavy metals (Cd, Cu, Ni, Pb, Zn), used as an indication of the general level of air pollution, and the total number of galls, were positive and generally highly significant. It is concluded that P. resinella has benefitted from air pollution although perhaps to less extent than some sap-sucking species.

The PDF includes an abstract in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
article id 5262, category Article
Markku Nygren. (1986). Männyn siementen syyskeräys. Silva Fennica vol. 20 no. 1 article id 5262. https://doi.org/10.14214/sf.a15441
English title: Autumn harvested Scots pine seeds: the effect of cone storage and germination conditions on germination capacity.
Original keywords: mänty; itävyys; dormanssi; siemenkeräys; lepotila; käpyjen varastointi
English keywords: Pinus sylvestris; Scots pine; germination capacity; seed dormancy; cone storage
Abstract | View details | Full text in PDF | Author Info

Six seed collections were made in September–December 1984 in a natural Scots pine (Pinus sylvestris L.) stand in Southern Finland. The seeds were germinated immediately after the cone collection and three photoperiods (0.8 and 24 hours) were used in germination tests.

The seeds collected in September and October possessed relative dormancy, i.e. they did not germinate in darkness and at 10°C. Later in November and December the seeds were capable to germinate in darkness and at low temperature also. The gradual change in germination capacity is attributed to chilling temperatures in natural environments or in cone storage.

The PDF includes a summary in English.

  • Nygren, E-mail: mn@mm.unknown (email)
article id 5259, category Article
Kari Löyttyniemi, Olli Uusvaara. (1986). Further tests for termite resistance of Finnish pine heartwood. Silva Fennica vol. 20 no. 1 article id 5259. https://doi.org/10.14214/sf.a15438
Keywords: Pinus sylvestris; heartwood; resistance; Macrotermitinae; insect attact
Abstract | View details | Full text in PDF | Author Info

The natural resistance of Finnish-grown Pinus sylvestris L. heartwood to Macrotermitinae termites was tested in Zambia in graveyard conditions. The heartwood exhibited some natural resistance but durability was, however, far from practical immunity. There was significant tree-to-tree variation in the resistance of heartwood of P. Sylvestris.

The PDF includes a summary in Finnish.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
  • Uusvaara, E-mail: ou@mm.unknown
article id 5255, category Article
Matti Kärkkäinen, Jukka Pietilä, Raili Vihola. (1985). Suomalaisten puulajien iskutaivutuslujuus tuoreena. Silva Fennica vol. 19 no. 4 article id 5255. https://doi.org/10.14214/sf.a15434
English title: Impact bending strength of Finnish tree species in green condition.
Original keywords: kuusi; mänty; rauduskoivu; harmaaleppä; haapa; hieskoivu; taivutuslujuus; iskutaivutuslujuus
English keywords: Populus tremula; Pinus sylvestris; Betula pendula; Picea abies; Betula pubescens; Alnus incana; impact bending strength
Abstract | View details | Full text in PDF | Author Info

There are great impact forces in mechanized harvesting and wood yard in the mills which can cause breaks in timber. The impact strength of timber in green condition was tested in temperatures of +18°C and -18°C using sawn pieces (20 x 20 x 300 mm) of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.), birch (Betula pendula Roth and B. pubescens Ehrh.), grey alder (Alnus incana L.) and aspen (Populus tremula L.). In addition, unbarked naturally round sticks (length 300 mm, diameter 15 and 35 mm) of the same species were tested.

The impact strength of round sticks was 1.5–4.4 times as great as that of sawn pieces. The reasons are possibly the avoidance of cell breaks at the surface as well as growth stresses. The frozen samples were clearly weaker than the unfrozen ones. As a rule, the impact bending strength increased with increased density of the species. However, the correlation varied greatly between species. If density was kept constant, an increase in the growth ring width decreased the impact strength. The reason may lie in the fracture mechanism.

The PDF includes a summary in English.

  • Kärkkäinen, E-mail: mk@mm.unknown (email)
  • Pietilä, E-mail: jp@mm.unknown
  • Vihola, E-mail: rv@mm.unknown
article id 5252, category Article
Kari Löyttyniemi. (1985). On repeated browsing of Scots pine saplings by moose (Alces alces). Silva Fennica vol. 19 no. 4 article id 5252. https://doi.org/10.14214/sf.a15431
Keywords: Pinus sylvestris; Scots pine; Finland; Alces alces; moose; seedling damages; browsing damage; elks
Abstract | View details | Full text in PDF | Author Info

The size, nutrient contents and terpene composition of needles of Scots pine (Pinus sylvestris L.) saplings untouched and repeatedly browsed by the moose (Alces alces L.) were compared. Material was collected from a 14-years old and 2.5 m high pine stand in Bromarv, Southern Finland. The average length and fresh and dry weight of the needles were measured, and nutrient content (N, P, K, Ca, Mg, B, Cu) was determined.

The needles of repeatedly browsed pines became long and robust. There was, however, no difference between the dry matter percentage between the needles. The average nitrogen content was higher in the rebrowsed trees. Nitrogen content is, however, not directly correlated with the palatability of pine needles. Even phosphorus and boron content were higher in the damaged trees. No difference was found in Ca, K, Mg and Cu contents of the browsed and control pine saplings.

The PDF includes a summary in Finnish.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
article id 5251, category Article
Markku Halinen. (1985). Männyn nuoruusvaiheen kasvunopeuden vaikutus sahatavaran laatuun. Silva Fennica vol. 19 no. 4 article id 5251. https://doi.org/10.14214/sf.a15430
English title: The effect of the growth rate of young Scots pine on the quality of sawn goods.
Original keywords: mänty; kasvunopeus; sahatavaran laatu; tukin koko; nuoruusvaihe
English keywords: Pinus sylvestris; Scots pine; ring width; diameter growth; sawlogs; quality of timber; sawn goods; early growth
Abstract | View details | Full text in PDF | Author Info

Totally 653 battens and planks sawn from butt logsof Scots pine (Pinus sylvestris L.) were chosen from 3 saw mills. The sawn goods were sorted according to normal sorting principles. In order to determine growth rate in the youth, the mean value of the average ring width was measured at the butt end at various distances from the pith.

The average ring width increased as the quality of the sawn goods decreased. The difference between the quality classes in ring width was measured between 2 and 4 cm from the pith. As the size of sawn goods, and, simultaneously, the log size increased, the average ring width increased in a given quality class. Research reinforced previous results, in which slow diameter growth of young Scots pines has been shown to reflect the good quality of sawn goods.

The PDF includes a summary in English.

  • Halinen, E-mail: mh@mm.unknown (email)
article id 5246, category Article
Matti Kärkkäinen, Markku Halinen. (1985). Mäntysahatukkien minimivaatimusten täsmentäminen. Silva Fennica vol. 19 no. 3 article id 5246. https://doi.org/10.14214/sf.a15425
English title: Reappraisal of minimum requirements of Scots pine saw logs.
Original keywords: mänty; sahatavara; oksaisuus; laatuvaatimukset; kuivien oksien läpimitta; mäntysahatukki
English keywords: Pinus sylvestris; Scots pine; saw logs; sawlog quality; knottiness; quality classification; sawn goods; diameter of dry knots
Abstract | View details | Full text in PDF | Author Info

A test sawing was made of 807 Scots pine (Pinus sylvestris L.) saw logs of varying size and quality. The most important knot characteristic affecting the value of sawn goods was the diameter of the thickest dry knot. The new minimum requirements for pine logs were proposed on the basis of top diameter of the log and the diameter of the thickest dry and living knot.

The PDF includes a summary in English

  • Kärkkäinen, E-mail: mk@mm.unknown (email)
  • Halinen, E-mail: mh@mm.unknown
article id 5243, category Article
Eljas Pohtila, Tapani Pohjola. (1985). Maan kunnostus männyn viljelyssä Lapissa. Silva Fennica vol. 19 no. 3 article id 5243. https://doi.org/10.14214/sf.a15422
English title: Soil preparation in reforestation of Scots pine in Lapland.
Original keywords: mänty; istutus; kulotus; maanmuokkaus; Lappi; laikutus; lautasauraus; uudistustavat; hajakylvö
English keywords: Pinus sylvestris; soil preparation; Scots pine; planting; regeneration methods; scalping; prescribed burning; disc ploughing; broadcast sowing
Abstract | View details | Full text in PDF | Author Info

The study deals with the interaction of various soil preparation and reforestation methods. The most favourable time of the year for broadcast sowing and the effect of stabilization after soil preparation on restocking were studied as special problems.

Prescribed burning, scalping and disc ploughing made a better combination with sowing than planting, and ploughing better combination with planting than sowing. The longer the period was between sowing and germination the fewer seedlings emerged. The best stocking was clearly resulted with sowing in June. Stabilization of soil after preparation had a negative effect on reforestation results.

The PDF includes a summary in English.

  • Pohtila, E-mail: ep@mm.unknown (email)
  • Pohjola, E-mail: tp@mm.unknown
article id 5239, category Article
Jussi Kuusipalo. (1985). On the use of tree stand parameters in estimating light conditions below the canopy. Silva Fennica vol. 19 no. 2 article id 5239. https://doi.org/10.14214/sf.a15418
Keywords: Pinus sylvestris; basal area; Picea abies; canopy; tree species composition; light conditions; light climate; number of stems; canopy coverage
Abstract | View details | Full text in PDF | Author Info

Especially in forest vegetation studies, the light climate below the canopy is of great interest. In extensive forest inventories, direct measurement of the light conditions is too time-consuming. Often only the standard tree stand parameters are available. The present study was undertaken with the aim to develop methods for estimation of the light climate on the basis of readily measurable tree stand characteristics. The study material includes 40 sample plots representing different kinds of more or less mature forest stands of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.).

In each forest stand, a set of hemipherical photographs was taken and standard tree stand measurements were performed. A regression approach was applied in order to elaborate linear models for predicting the canopy coverage. The total basal area of the stand explained 63% of variance in the canopy coverage computed from hemipherical photographs. A coefficient representing the relative proportion of Norway spruce in the stand increased the explanatory power into 75%. When either the stand density (stems/unit area) or dominant age of the stand was included into the model, increment of the explanatory power into 80% was achieved. By incorporating both of the preceding predictors, an explanatory power of 85% was reached.

The PDF includes a summary in Finnish.

  • Kuusipalo, E-mail: jk@mm.unknown (email)
article id 5237, category Article
Leo Heikurainen, Jukka Laine. (1985). Duration of the height growth response of young pine stands to NPK-fertilization on oligotrophic pine bogs in Finland. Silva Fennica vol. 19 no. 2 article id 5237. https://doi.org/10.14214/sf.a15416
Keywords: Pinus sylvestris; fertilization; drained peatlands; Scots pine; Finland; climate; growth; degree days
Abstract | View details | Full text in PDF | Author Info

This is the latest report in a series of publications from an on-going investigation which is concerned with the influence of different fertilization treatments and ditch spacings on the growth of Scots pine (Pinus sylvestris L.) seedlings and transplants growing on nutrient drained poor bogs in different parts of Finland. This paper concentrates on duration of the growth response to NPK-fertilization on the experimental plots. The experiment was established and the treatments performed in 1965–66.

The results show that climate, expressed as effective temperature sum (dd°C, threshold +5°C) has a clear influence on the duration of the fertilization effect. In Southern Finland (>1,200 dd°C), the duration was at least 15 years. In Central Finland (1,200–1,000 dd°C), it appears to be almost 10 years, and in Northern Finland (<1,000 dd°C), slightly shorter. The amount of fertilizer applied clearly influenced the duration of the fertilization effect. The dosage of 500 kg/ha (N 14, P 7.8, K 8.3 per cent) had, on average, a shorter duration than the greater dosages of 1,000 and 1,500 kg/ha. However, there was no clear difference between the latter two dosages.

The PDF includes a summary in Finnish.

  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Laine, E-mail: jl@mm.unknown
article id 5226, category Article
Antti Uotila. (1985). Männynversosyövän leviämisestä tautipesäkettä ympäröiviin terveisiin mäntyihin. Silva Fennica vol. 19 no. 1 article id 5226. https://doi.org/10.14214/sf.a15405
English title: The spreading of Ascocalyx abietina to healthy Scots pines in the vicinity of diseased trees.
Original keywords: mänty; taudinkestävyys; sienitaudit; torjunta; surmakka; versosurma; alkuperät
English keywords: Pinus sylvestris; Scots pine; Gremmeniella abietina; pathogen resistance; pathogens; Ascocalyx abietina; proveniences; sanitation cuttings
Abstract | View details | Full text in PDF | Author Info

Ascocalyx abietina (now Gremmeniella abietina Lagerb.) infects Scots pine (Pinus sylvestris L.) by means of ascospores or conidia. Ascospores are dispersed by the wind, while the conidia are splash dispersed. The infection rate is positively correlated with the number of inocula. The aim of this study was to determine the extent to which G. abietina spreads to the trees surrounding the diseased trees and to find the correct time to perform sanitation cutting.

The results were obtained from Ascocalyx-inventory carried out in a Scots pine progeny test at Loppi, Southern Finland. Three Siberian provenances were totally destroyed, while the Finnish progenies remained relatively healthy. The two rows adjacent to the destroyed plots were inventoried separately.

There were 29.7% more diseased or dead trees in the two adjacent rows than in the rest of the same plots. The difference was statistically significant. The trees had probably been infected by conidia, because the effect of the destroyed plot only extended to the adjacent two rows. Furthermore, pycnidia had mainly developed on the dead shoots.

On the basis of the life cycle of the fungus and the results, the correct time to carry out sanitation cutting is the first winter after the disease symptoms have appeared. If it is done later, the disease could be spread and bark beetles (Tomicus spp.) could propagate in dying trees. Susceptible provenances may spread the disease to surrounding resistant trees owing to the increasing number of spores.

The PDF includes a summary in English.

  • Uotila, E-mail: au@mm.unknown (email)
article id 5218, category Article
Jouni Suoheimo. (1984). Isokorvakärsäkkään aikuisten esiintyminen ja merkitys männyn luontaiselle uudistamiselle Pohjois-Lapissa. Silva Fennica vol. 18 no. 3 article id 5218. https://doi.org/10.14214/sf.a15397
English title: The occurrence of Otiorrhynchus nodosus and its significance for the natural regeneration of Scots pine in Lapland.
Original keywords: hyönteistuhot; mänty; luontainen uudistaminen; taimituhot; Pohjois-Lappi; isokorvakärsäkäs
English keywords: Pinus sylvestris; natural regeneration; Scots pine; insect damage; seedling damages; weevils; occurrence
Abstract | View details | Full text in PDF | Author Info

The aim of the present study was to survey the occurrence of Otiorrhynchus nodosus Müller weevils and their significance for the natural regeneration of Scots pine (Pinus sylvestris L.). The study was carried out during summer 1982 at Inari in northern Lapland.

There were two sample plots, one situated in a Scots pine seed-tree area and the other, the control sample plot, in an area with a coverage of mountain birch (Betula pubescens subsp. tortuosa, now subsp. czerepanovii). A total of 177 Otiorhynchus weevils were caught. Movement of the weevils reached its climax in July. There were 86% more individuals in the seed-tree area than in the mountain birch area. No damage to the pine germlings or seedlings was not observed, although the situation could be different during the peaks of the veewil populations.

The PDF includes a summary in English.

  • Suoheimo, E-mail: js@mm.unknown (email)
article id 5213, category Article
Bo Långström. (1984). Windthrown Scots pines as brood material for Tomicus piniperda and T. minor. Silva Fennica vol. 18 no. 2 article id 5213. https://doi.org/10.14214/sf.a15392
Keywords: Pinus sylvestris; bark beetles; Scots pine; wind damages; breeding; Sweden; Tomicus piniperda; Tomicus minor; insect damage; egg galleries
Abstract | View details | Full text in PDF | Author Info

In the 1980 and 1981, windthrown and felled Scots pine (Pinus sylvestris L.) were examined at 8 localities in Sweden. The number and length of egg galleries as well as the number of exit holes of Tomicus piniperda (L.) and T. minor (Hart.) were recorded on sample sections (30 m in length) distributed at 3 m intervals on the 37 fallen pine stems, which were successfully colonized by the beetles. In addition, 78 uprooted pines were surveyed in 6 localities. Most trees were attacked by T. piniperda, but only a few by T. minor. Successful colonization often resulted in the production of several thousand beetles per tree, the maximum being approximately 1,800. The attack density of T. piniperda seldom exceeded 200 egg galleries/m3 bark area, and the brood production usually remained below 1,000 beetles/m3. Much higher figures were obtained or T. minor. In T. piniperda, the rate of reproduction (i.e. the number of exit holes /egg gallery) decreased rapidly with increasing attack density, whereas T. minor seemed to be less sensitive to intraspecific competition.

The PDF includes a summary in Finnish.

  • Långström, E-mail: bl@mm.unknown (email)
article id 5207, category Article
Seppo Kellomäki. (1984). Havaintoja puuston kasvatustiheyden vaikutuksesta mäntyjen oksikkuuteen. Silva Fennica vol. 18 no. 2 article id 5207. https://doi.org/10.14214/sf.a15386
English title: Observations on the influence of stand density on branchiness of young Scots pines.
Original keywords: mänty; oksikkuus; oksan läpimitta; metsikön tiheys; kasvatustiheys; kuolleet oksat; elävät oksat
English keywords: Pinus sylvestris; Scots pine; stand density; branchiness; branch diameter
Abstract | View details | Full text in PDF | Author Info

The study based on young Scots pine (Pinus sylvestris L.) of varying density showed that number of living branches per whorl and total number of living branches per tree were negatively correlated with stand density. On the contrary, the number of dead branches increased with increasing stand density. The diameter of living and dead branches decreased with increasing stand density. Consequently, the branchiness, i.e. the share of the branch cross-sectional area from the surface area of the stem, decreased in dense stands compared with the thin stands. At the densest stands the branchiness, however, levelled of indicating a greater decrease of the radial growth at stems than at branches. The 2/3 power law described relatively well the relationship between stand density and mean squared branch diameter of living branches.

The PDF includes a summary in English.

  • Kellomäki, E-mail: sk@mm.unknown (email)
article id 5204, category Article
Pirkko Velling, P. M. A. Tigerstedt. (1984). Harvest index in a progeny test of Scots pine with reference to the model of selection. Silva Fennica vol. 18 no. 1 article id 5204. https://doi.org/10.14214/sf.a15383
Keywords: Pinus sylvestris; yield; Scots pine; tree breeding; heritability; harvest index; progeny test
Abstract | View details | Full text in PDF | Author Info

Harvest index and number of associated traits were measured in a 16-year-old Scots pine (Pinus sylvestris L.) progeny test based on full-sib families. It was found that harvest index is a highly heritable trait and that a number of yield components are positively correlated with it. It is suggested that harvest index and tree ideotypes should be the basis of selection in cultivated trees. It is emphasized that an integrated approach to tree improvement including silviculture, soil science, industrial and economic constraints and tree breeding is a prerequisite for maximal response.

The PDF includes a summary in Finnish.

  • Velling, E-mail: pv@mm.unknown (email)
  • Tigerstedt, E-mail: pt@mm.unknown
article id 5198, category Article
Leo Heikurainen, Jukka Laine, Jarmo Lepola. (1983). Lannoitus- ja sarkaleveyskokeita karujen rämeiden uudistamisessa ja taimikoiden kasvatuksessa. Silva Fennica vol. 17 no. 4 article id 5198. https://doi.org/10.14214/sf.a15181
English title: Fertilization and ditch spacing experiments concerned with regeneration and growth of young Scots pine stands on nutrient poor pine bogs.
Original keywords: mänty; luontainen uudistaminen; istutus; uudistaminen; lannoitus; ojitetut suot; taimikot; pituuskasvu; sarkaleveys
English keywords: Pinus sylvestris; fertilization; regeneration; natural regeneration; drained peatlands; Scots pine; height growth; planting; ditch spacing
Abstract | View details | Full text in PDF | Author Info

The effects of variations in the intensity of drainage and NPK fertilization on the natural regeneration and planting results and the subsequent development of seedling stands under various climatic conditions on drained nutrient poor pine bogs was investigated in a 16-year-old study.

Comparison of height development of Scots pine (Pinus sylvestris L.) stands on drained peatlands to that of pine stands growing in mineral soil sites show that in Southern Finland the most efficient forest improvement measures (10 m ditch spacing and 1,000 kg/ha NPK-fertilization) resulted in growth that corresponds a to a height index of a stand in a Vaccinium type site. Less efficient treatment (30 m ditch spacing and no fertilizer) resulted in growth corresponding the development of young stand in a Calluna type site. In Northern Finland the effect of fertilization on height growth was almost negligible. This is possibly due to a decrease in the nitrogen mobilization from south to north of Finland. Thus, it seems evident that fertilization of young Scots pine stands on nutrient poor drained peatlands can be recommended only in the southern part of the country.

The effect of ditch spacing is same in the whole country. The narrower the spacing the better the height growth. In the south planted stands thrive better than naturally regenerated stands, but the situation is reversed in the north.

The PDF includes a summary in English.

  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Laine, E-mail: jl@mm.unknown
  • Lepola, E-mail: jl@mm.unknown
article id 5197, category Article
Kari Heliövaara, Erkki Annila, Eero Terho. (1983). Effect of nitrogen fertilization and insecticides on the population density of pine bark bug, Aradus cinnamomeus (Heteroptera, Aradidae). Silva Fennica vol. 17 no. 4 article id 5197. https://doi.org/10.14214/sf.a15180
Keywords: Pinus sylvestris; fertilization; Scots pine; height growth; insecticides; insect damages; prevention; nitrogen fertilization; Aradus cinnamomeus
Abstract | View details | Full text in PDF | Author Info

The effect of nitrogen fertilization and two insecticides on the occurrence of the plant pine bark bug, Aradus cinnamomeus Panzer, was investigated in a young Scots pine (Pinus sylvestris L.) stand in Southern Finland. Three years after the treatment the bug density was lowest in the trees treated with lindane or dimethoate. However, in spite of the increasing height growth of the trees, they did not grow significantly faster than the control trees. Nitrogen fertilization increased both bug density and the height growth of the trees. Thus, the value of nitrogen fertilization against Aradus cinnamomeus remains obscure.

The PDF includes a summary in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
  • Annila, E-mail: ea@mm.unknown
  • Terho, E-mail: et@mm.unknown
article id 5195, category Article
Matti Rousi. (1983). Susceptibility of pine to mammalian herbivores in northern Finland. Silva Fennica vol. 17 no. 4 article id 5195. https://doi.org/10.14214/sf.a15178
Keywords: Pinus sylvestris; fertilization; Scots pine; Alces alces; moose; forest damage; seedling damages; arctic hare; Lepus timidus; root vole; Microtus oeconomus; bank vole; Microtus agrestis
Abstract | View details | Full text in PDF | Author Info

An inventory of Scots pine (Pinus sylvestris L.) graft collection in Kolari (67°15’ N, 23°45’ S) showed that severe damage by arctic hare (Lepus timidus L.), root and bank vole (Microtus oeconomus Pallas and M. agrestis L.) and moose (Alces alces L.) was done to grafts in size and in rather poor condition. Furthermore, the damage by arctic hare was dependent on the dry matter content of the needles. Another inventory in a fertilization experiment in a pine pole-stage forest showed that nitrogen fertilization increased the damage by arctic hare. On the basis of the present results, an assumption was made that the formation of repellent substances against herbivorous mammals is connected with wintering process of northern pines.

The PDF includes a summary in Finnish.

  • Rousi, E-mail: mr@mm.unknown (email)
article id 5193, category Article
Juhani Jokinen, Antti Häkkinen, Reijo Karjalainen, Kari Markkanen, Tapani Säynätkari. (1983). Effects of air pollution on Scots pine needles. I. Silva Fennica vol. 17 no. 3 article id 5193. https://doi.org/10.14214/sf.a15176
Keywords: Pinus sylvestris; needles; Scots pine; air pollution; sulphur dioxide; peroxidase activity
Abstract | View details | Full text in PDF | Author Info

The effect of meteorological factors, the total sulphur content of the needles, and SO2 concentration in the ambient air on total peroxidase activity of Scots pine (Pinus sylvestris L.) needles was investigated in material obtained from Southern Finland. The correlation between temperature and total peroxidase activity was highest during the most active growing period. Linear correlation between relative humidity and total peroxidase activity appears to be low. The correlation between atmospheric SO2 concentration and total peroxidase activity was also low and varied inconsistently. The detected low association between the sulphur dioxide pollutant and the total peroxidase activity was assumed to be related to the sensitivity of peroxidase activity, many eco-physiological factors and to the genetic variation in conifers. It is difficult to separate a response due to this pollutant from environmental and genetic factors in a complex coniferous forest. Using total peroxidase activity as a routine indicator of air pollution seems to be unsuitable because of the large sample size required in order to obtain a reliable measurement of the pollutant’s effect under low pollution levels.

The PDF includes a summary in Finnish.

  • Jokinen, E-mail: jj@mm.unknown (email)
  • Häkkinen, E-mail: ah@mm.unknown
  • Karjalainen, E-mail: rk@mm.unknown
  • Markkanen, E-mail: km@mm.unknown
  • Säynätkari, E-mail: ts@mm.unknown
article id 5189, category Article
Anneli Viherä, Seppo Kellomäki. (1983). Havaintoja nuorten mäntyjen latvusten hienorakenteesta ja kasvusta. Silva Fennica vol. 17 no. 3 article id 5189. https://doi.org/10.14214/sf.a15172
English title: Observations on structure and growth of crowns of young Scots pines.
Original keywords: mänty; versot; neulaset; biomassa; oksat; latvus; latvuksen rakenne; valaistusolot
English keywords: Pinus sylvestris; biomass; needles; Scots pine; branches; crown; light conditions; shoots; structure of the crown
Abstract | View details | Full text in PDF | Author Info

A study based on four young Scots pines (Pinus sylvestris L.) showed that the number of needle-covered shoots per crown volume unit was independent on tree position representing a constant value of 600–700 shoots/m3. This was true, even though the total shoot number decreased with deteriorating tree position. In tree crown there were fourth-order shoots in good light conditions but only first- and second-order-shoots, when light conditions were poor. The length of shoots decreased in accordance with increasing order of the shoot.

The share of the needle biomass and growth increased, when the shoot order increased. Similarly, the share of needles increased with deteriorating tree position. This was especially true in the upper crown. On the other hand, the share of the crown from the total biomass and growth increased with improving tree position. The percentage of crown system of a dominant tree in a sparse stand was 64% of that of biomass and 83% of that of growth. The corresponding values for a suppressed tree in a dense stand were 36% and 35%. The growth of wood, bark and needles in crown systems was linearly correlated with prevailing light conditions around the branch. It is evident that the tree position and light condition within the stand control the wood, bark and needle growth in the crown system and their interrelationships.

The PDF includes a summary in English.

  • Viherä, E-mail: av@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
article id 5188, category Article
Eljas Pohtila, Tapani Pohjola. (1983). Vuosina 1970-1972 Lappiin perustetun aurattujen alueiden viljelykokeen tulokset. Silva Fennica vol. 17 no. 3 article id 5188. https://doi.org/10.14214/sf.a15171
English title: Results from the reforestation experiment on ploughed sites established in Finnish Lapland during 1970–1972.
Original keywords: kuusi; kylvö; mänty; istutus; maanmuokkaus; Lappi; uudistaminen; kuolleisuus; rauduskoivu; siperianlehtikuusi; auraus
English keywords: Pinus sylvestris; Norway spruce; Betula pendula; Picea abies; regeneration; soil preparation; Scots pine; silver birch; planting; ploughing; Lapland; mortality; Siberian larch; sowing; Larix sibirica
Abstract | View details | Full text in PDF | Author Info

The objective of the study was to compare different reforestation methods on ploughed areas in Finnish Lapland. Four species were compared: Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.), silver birch (Betula pendula Roth) and Siberian larch (Larix sibirica Ledeb.). The experiments were established in different parts of Lapland on different types of sites in 1970–72.

In Scots pine there was a difference of 15 percentage points in survival of seedlings between the best and worst methods of regeneration. Containerized seedlings and paper pot seedlings had the best survival rates. In Norway spruce the respective difference between sowing and planting was about 20 percentage points. In favour of planting. The survival rate can be increased by about 20 percentage points by selecting the right tree species. The average height varied from 25 cm (the sowed Norway spruce) to 179 cm (the planted silver birch) after 10 growing seasons. The birch was planted at the most fertile sites only. The longer time passed from the afforestation the clearer was the effect of the local growing conditions on the development of the seedlings. The elevation of the site was one factor seemed to influence the success of the seedlings.

The PDF includes a summary in English.

  • Pohtila, E-mail: ep@mm.unknown (email)
  • Pohjola, E-mail: tp@mm.unknown
article id 5187, category Article
Fuhe Luo. (1983). Determination of stem value. Silva Fennica vol. 17 no. 3 article id 5187. https://doi.org/10.14214/sf.a15170
Keywords: Pinus sylvestris; Scots pine; modelling; pulpwood; saw log; stem value; taper curve model; bark model; cubic spline interpolation
Abstract | View details | Full text in PDF | Author Info

A dynamic programming approach toward stem value estimation for standing Scots pine (Pinus sylvestris L.) trees was developed. The determination of the saw log value was based on the sawing pattern and on the final products composition. The combination of taper curve models and bark models providing taper curves both over bark and under bark, which constituted the basis of the optimum stem scaling. A computer program was developed to determine the optimum log sequence of the stem aiming at maximizing the value of the final products. To examine the reliability of the computation system, 445 Scots pine sample trees from 29 stands were used as a test material. The stem values of sample trees were calculated in two ways: 1) with 12 measured diameters, and 2) with 12 estimated diameters derived from measured tree characteristics. In both cases the values of the intermediate diameters were calculated via cubic spline interpolation.

The PDF includes a summary in Finnish.

  • Luo, E-mail: fl@mm.unknown (email)
article id 5185, category Article
Seppo Kellomäki. (1983). Männyn oksien murtolujuus. Silva Fennica vol. 17 no. 2 article id 5185. https://doi.org/10.14214/sf.a15101
English title: Strength of Scots pine branches.
Original keywords: mänty; oksikkuus; oksat; lujuus; karsiutuminen; puun tiheys
English keywords: Pinus sylvestris; Scots pine; strength; basic density; branches; self-pruning
Abstract | View details | Full text in PDF | Author Info

Empirical measurements showed that the strength of a dead branch of Scots pine (Pinus sylvestris L.) was related to the second power of the branch diameter and the third power of the basic density of branch wood. The same factors affected also the strength of living branches. Especially, the contribution of wood density was important. The significance of the results is discussed considering the natural process of self-pruning and its effect on the branchiness of the stem.

The PDF includes a summary in English.

  • Kellomäki, E-mail: sk@mm.unknown (email)
article id 5177, category Article
Kari Löyttyniemi. (1983). Preliminary testing of the resistance of Finnish softwood timbers to Macrotermitinae termites. Silva Fennica vol. 17 no. 1 article id 5177. https://doi.org/10.14214/sf.a15092
Keywords: Pinus sylvestris; insect damages; insect resistance; Macrotermitinae termites; sofwood timber; Juniperus communis; Microtermes; Odontotermes; Zambia
Abstract | View details | Full text in PDF | Author Info

The resistance of Finnish softwood timbers to Macrotermitinae termites was tentatively tested under tropical conditions in Zambia using a field microtest method. Picea abies (L.) H. Karst. and Larix sibirica L. sapwood and heartwood, as well as Pinus sylvestris L. sapwood, and the sapwood of the locally grown Pinus kesiya, exhibited no natural termite resistance. On the other hand, Juniperus communis heartwood appeared to be virtually immune and the heartwood of P. Sylvestris had some resistance. There were also some differences in the resistance of the heartwood of the different P. Sylvestris individuals tested, which was correlated with the width of the annual rings in the wood samples. The termite species involved were Microtermes sp. and Odontotermes sp. The possibilities of using different types of Finnish softwood timber in the regions in the tropics where there is a risk of termite damage is discussed.

The PDF includes a summary in Finnish.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
article id 5171, category Article
Seppo Kellomäki, Pauline Oker-Blom. (1983). Canopy structure and light climate in a young Scots pine stand. Silva Fennica vol. 17 no. 1 article id 5171. https://doi.org/10.14214/sf.a15086
Keywords: Pinus sylvestris; needles; Scots pine; canopy; needle biomass; crown; needle area; light condition; within-stand light regime
Abstract | View details | Full text in PDF | Author Info

The needle area distribution and crown structure of a young planted Scots pine (Pinus sylvestris L.) stand are described. The crown structure and crown shape showed apparent regularity in crown structure regardless of stand dynamics. Similarly, the shoot structure and individual needle area showed regularity in the number of needles per branch and shoot length unit, and consequent phytoarea density inside the needle cylinder. Also, the shoot area and needle area distributions were found to show a regular distribution of needle biomass throughout the crown, also inside the crown, in the dominant trees. In the suppressed trees the needle biomass was located in the upper crown and on the surface area of the crown. Estimates of the canopy needle area and distributions are given. The results were applied in calculations of the within-stand light regime. The results correlated well with the empirical results.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Oker-Blom, E-mail: po@mm.unknown
article id 5169, category Article
Seppo Kellomäki, Pasi Puttonen, Heikki Tamminen, Carl Johan Westman. (1982). Effect of nitrogen fertilization on photosynthesis and growth in young Scots pines. Preliminary results. Silva Fennica vol. 16 no. 4 article id 5169. https://doi.org/10.14214/sf.a15084
Keywords: Pinus sylvestris; fertilization; Scots pine; stem growth; nitrogen fertilization; needle area; photosynthetic rate
Abstract | View details | Full text in PDF | Author Info

Application of nitrogen at levels of 200, 400 and 600 kg ha-1 resulted in increases of 35, 18 and 12% in the photosynthetic rate in young Scots pine (Pinus sylvestris L.). The number of buds, degree of branching, and needle size were positively related to the amount of nitrogen applied. A 10–40% increase in the average needle area was found. A positive correlation was found between total photosynthesis and stem growth.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Puttonen, E-mail: pp@mm.unknown
  • Tamminen, E-mail: ht@mm.unknown
  • Westman, E-mail: cw@mm.unknown
article id 5168, category Article
Kari Heliövaara. (1982). The pine bark bug, Aradus cinnamomeus (Heteroptera, Aradidae) and the height growth rate of young Scots pines. Silva Fennica vol. 16 no. 4 article id 5168. https://doi.org/10.14214/sf.a15083
Keywords: Pinus sylvestris; Scots pine; height growth; insect damages; Aradus cinnamomeus
Abstract | View details | Full text in PDF | Author Info

Relationships between densities of pine bark bug, Aradus cinnamomeus Panzer and the height growth of young Scots pine (Pinus sylvestris L.) were studied in several habitats, including a highly infested area in Southern Finland. The slower the growth of the pines was, the greater was the height up to which bugs were found. On the average, maximum bug density was noted at a height corresponding to a fifth of the height of the tree. In stands restocked by natural generation, the greatest bug densities were noted in pines about three metres high and over twenty years old. Bug densities in trees whose height growth had been decelerating for five years were twice those in trees whose growth was accelerating. A significant negative correlation was found between the bug density and the last-year height increment.

The PDF includes a summary in Finnish.

  • Heliövaara, E-mail: kh@mm.unknown (email)
article id 5157, category Article
Eino Mälkönen, Vesa Aro-Heinilä, Seppo Kellomäki. (1982). Lannoituksen ja kastelun vaikutus männikön pintakasvillisuuteen. Silva Fennica vol. 16 no. 1 article id 5157. https://doi.org/10.14214/sf.a15072
English title: Effect of fertilization and irrigation on the ground vegetation of a Scots pine stand.
Original keywords: mänty; lannoitus; kastelu; aluskasvillisuus; peittävyys; heinät; varvut; kanerva
English keywords: Pinus sylvestris; fertilization; irrigation; Scots pine; ground vegetation; dwarf shrubs; grasses; Calluna vulgaris
Abstract | View details | Full text in PDF | Author Info

A mature Scots pine (Pinus sylvestris L.) stand growing on a site of the Vaccinium type in Southern Finland was fertilized with nitrogen-rich NPK fertilizer at a level of 150 kg pure nitrogen per hectare. The sample plots were also irrigated during four growing seasons. The total amount of irrigation during this period was 1,200 mm. Fertilization alone increased the coverage of grasses and dwarf shrubs. The culmination of the increase occurred during the second growing season after the start of the treatment. The rapid effect of irrigation on the coverage of ground vegetation was not so strong as that of fertilization. It was concluded on the basis of the developed growth model that the coverage of dwarf shrubs, especially Calluna vulgaris, was, however, increased with the fertilization treatment for a prolonged period. Fertilization and irrigation had no visible effect on the coverage of lichens and mosses.

The PDF includes a summary in Finnish.

  • Mälkönen, E-mail: em@mm.unknown (email)
  • Aro-Heinilä, E-mail: va@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
article id 5153, category Article
T. Raunemaa, R. Erkinjuntti, M. Gerlander, A. Hautojärvi, K. Kaisla, H.-S. Katainen. (1981). Multielement analysis of treated pine seedlings. Silva Fennica vol. 15 no. 4 article id 5153. https://doi.org/10.14214/sf.a15380
Keywords: Pinus sylvestris; needles; photosynthesis; Scots pine; roots; air pollution; acid rain; environmental impact; acid deposition; elemental concentrations
Abstract | View details | Full text in PDF | Author Info

A comparison study concerning the effects of acid rain on Scots pine (Pinus sylvestris L.) seedlings has been performed. Two different X-ray fluorescence methods, PIXE and IXRF, were employed to produce multielement analyses of the samples. Seedlings were treated for 3 months with watering of pH=7 or pH=3 liquids on the needles and on the roots. One year and two years old needles of the seedlings were inspected for changes in photosynthetic rate as well as for changes in elemental concentrations.

Twelve elements from Si to Zn were compared in the samples. The PIXE results show that the amounts of most of these elements in the needles of the seedlings grown in sand increase, when treated with acid water. This growth is clearer when the roots are treated with acid water. The elemental concentrations of the needles in the seedlings grown in soil on the other hand decrease slightly.

  • Raunemaa, E-mail: tr@mm.unknown (email)
  • Erkinjuntti, E-mail: re@mm.unknown
  • Gerlander, E-mail: mg@mm.unknown
  • Hautojärvi, E-mail: ah@mm.unknown
  • Kaisla, E-mail: kk@mm.unknown
  • Katainen, E-mail: hk@mm.unknown
article id 5148, category Article
A. Hautojärvi, S. Ahonen, R. Erkinjuntti, H.-S. Katainen, T. Lappalainen, T. Raunemaa. (1981). Surface concentration of sulphur on Scots pine needles. Silva Fennica vol. 15 no. 4 article id 5148. https://doi.org/10.14214/sf.a15375
Keywords: Pinus sylvestris; needles; Scots pine; Finland; coal; air pollution; measurement methods; environmental impact; sulphur; power plant; sulphate
Abstract | View details | Full text in PDF | Author Info

A method to determine sulphur as sulphate has been applied to search for surface concentration of sulphate sulphur on needle samples. The method is based on reducing sulphates as volatile hydrogen sulphide gas by using hydriodic acid. The hydrogen sulphide gas is swept with nitrogen into an absorbent solution. Sulphide ion concentration in solution is then measured using ion selective electrodes.

The method was applied on one to four years old needle samples collected from Scots pine (Pinus sylvestris L.) at 0.9 to 15.9 km distances from a 1,064 MW coal-fired power plant in Southern Finland. Surface sulphate values found in the samples closer than 4 km to the power plant were 50 to 100% higher than a nearly constant background level. No significant variation of values with needle age was found. The advantages of the method compares to other methods for sulphur determination are speed, reasonable sensitivity and low detection limit.

  • Hautojärvi, E-mail: ah@mm.unknown (email)
  • Ahonen, E-mail: sa@mm.unknown
  • Erkinjuntti, E-mail: re@mm.unknown
  • Katainen, E-mail: hk@mm.unknown
  • Lappalainen, E-mail: tl@mm.unknown
  • Raunemaa, E-mail: tr@mm.unknown
article id 5146, category Article
J. N. Cape, D. Fowler. (1981). Changes in epicuticular wax of Pinus sylvestris exposed to polluted air. Silva Fennica vol. 15 no. 4 article id 5146. https://doi.org/10.14214/sf.a15373
Keywords: Pinus sylvestris; needles; Scots pine; damage; air pollution; environmental impact; sulphur dioxide; foliage; epicuticular vax; cuticular transpiration
Abstract | View details | Full text in PDF | Author Info

Scanning Electron Microscopy was used to study structural changes in epicuticular vax of Pinus sylvestris L. with time. Changes in the contact angle of water droplets and in cuticular transpiration were also measured. By using material from a polluted and an unpolluted site it was shown that the ageing process occurs faster on polluted air, leading to greater cuticular transpiration and smaller contact angles at polluted sites.

  • Cape, E-mail: jc@mm.unknown (email)
  • Fowler, E-mail: df@mm.unknown
article id 5139, category Article
Boguslaw Molski, Andrzej Bytnerowicz, Wojciech Dmuchowski. (1981). Content of sulphur and fluorine compounds in Scots pine needles as an indicator of air pollution in Poland. Silva Fennica vol. 15 no. 4 article id 5139. https://doi.org/10.14214/sf.a15366
Keywords: Pinus sylvestris; needles; Scots pine; inventory; Poland; air pollution; sulphur; soluble fluorides; Warsaw; Plock; chemical analysis
Abstract | View details | Full text in PDF | Author Info

Our preliminary findings indicate that the content of total sulphur and soluble fluorides in needles of the Scots pine (Pinus sylvestris L.) reflects the degree of air pollution with sulphur and fluorine compounds. A project for a map of air pollution in Poland, based on chemical analysis of Scots pine needles, is presented. Results of the total sulphur and soluble fluoride content in 2-year old needles from 15- to 25-year-old trees should yield a picture of air pollution with sulphur and fluorine compounds. The first stage will involve the preparation of a map of the area between the Warsaw and Plock agglomerations. This area will be divided into 10 squares with side dimension of 25 km each. Samples will be taken at 5 different sites in each square and also approximately every 5 km along a straight line between these towns.

  • Molski, E-mail: bm@mm.unknown (email)
  • Bytnerowicz, E-mail: ab@mm.unknown
  • Dmuchowski, E-mail: wd@mm.unknown
article id 5138, category Article
K. Kvist, C. Jakobsson. (1981). Vegetation injury occurring after winter at a fertilizer factory. Silva Fennica vol. 15 no. 4 article id 5138. https://doi.org/10.14214/sf.a15365
Keywords: Pinus sylvestris; nitrogen; needles; Scots pine; Sweden; emissions; air pollution; sulphur; fertilizer plant; fluorine
Abstract | View details | Full text in PDF | Author Info

Air pollution injury to vegetation often occurs near a fertilizer factory in Central Sweden. The causing incidence often occurs in the winter and the symptoms appear when metabolism starts in the spring. Deciduous and coniferous trees and bushes were injured in the spring of 1979. Samples of Scots pine (Pinus sylvestris L.) needles were analysed for sulphur, total fluorine and nitrogen content, some of them for nitrate and ammonium. All the compounds showed elevated levels, clearly connected with the degree of exposure of the sampling site. The levels were higher in the spring than later in the growing season, indicating involvement in metabolism or leaching. None of the compounds was significantly in excess, although, elevated to an extent to indicate the cause of injury. Most probably the nitrogen compounds were involved. The problems encountered in tracing the causing pollutant, when injury appeared long after the incidence, might be easier solved with regularly used technical monitoring and bioindicator technique.

  • Kvist, E-mail: kk@mm.unknown (email)
  • Jakobsson, E-mail: cj@mm.unknown
article id 5136, category Article
Sirkka Soikkeli. (1981). The types of ultrastructural injuries in conifer needles of northern industrial environments. Silva Fennica vol. 15 no. 4 article id 5136. https://doi.org/10.14214/sf.a15363
Keywords: Pinus sylvestris; Norway spruce; Picea abies; needles; Scots pine; emissions; air pollution; cell organelles; mesophyll
Abstract | View details | Full text in PDF | Author Info

Ultrastructure of mesophyll of second-year green needles of Picea abies (L.) H. Karst. and Pinus sylvestris (L.) has been studied in several polluted areas in Finland since 1976 (Soikkeli and Tuovinen 1979, Soikkeli 1981a). Four different types of injuries have been found. The types differ with the origin of the material:

1) In needles collected from areas pollute by S-communds the types with reduced grana and/or the with lightening of plastogobuli with simultaneous accumulation of lipid-like material are observed.

2) In needles expose to fluorides (alone or in addition to other pollutants) the type with swollen and/or that with curled thylakoids are found. Both of the latter have also stretched envelopes. In each type of the injury three stages of cell disruption have been described: slight-medium, severe and very severe. On the slight-medium stage the injuries are usually found only in chloroplasts. On severe stage other organelles show injuries, too. In very severe injury all cell organelles are badly disorganized or they disappear completely. The most abundant injuries are usually in needles collected after their second winter. The severity of cell injury depends on the closeness of emission source or on the measured concentration of SO2.

  • Soikkeli, E-mail: ss@mm.unknown (email)
article id 5135, category Article
L. Skärby, C. Bengtson, C.-Å. Boström, P. Grennfelt, E. Troeng. (1981). Uptake of NOx in Scots pine. Silva Fennica vol. 15 no. 4 article id 5135. https://doi.org/10.14214/sf.a15362
Keywords: Pinus sylvestris; Scots pine; acidification; air pollution; environmental impact; sulphur oxide; nitrogen oxide
Abstract | View details | Full text in PDF | Author Info

Information on input of acidifying compounds like SO2 and NOx is necessary to understand effects of acidification. The uptake on NO and NO2 respectively was studied on seedlings and shoots of Scots pine (Pinus sylvestris L.). Experiments were conducted both in laboratory (NO and NO2 respectively) and in the field (NO2) under light and dark conditions. In all three cases there was a linear relationship between the uptake rate and the NOx-concentration. The uptake follows a diurnal pattern i.e. the uptake rate was strongly correlated with the stomatal movements. Uptake rates were converted to deposition rate and the results showed that field exposure with NO2 gave the higher deposition rate.

  • Skärby, E-mail: ls@mm.unknown (email)
  • Bengtson, E-mail: cb@mm.unknown
  • Boström, E-mail: cb@mm.unknown
  • Grennfelt, E-mail: pg@mm.unknown
  • Troeng, E-mail: et@mm.unknown
article id 5131, category Article
Risto Jalkanen, Satu Huttunen, Teija Väisänen. (1981). The wax structure of the developing needles of Pinus sylvestris progenies infected by Lophodermella sulcigena. Silva Fennica vol. 15 no. 4 article id 5131. https://doi.org/10.14214/sf.a15188
Keywords: Pinus sylvestris; Scots pine; disease resistance; pathogens; Lophodermella sulcigena; progenies; needle structure; stomatal cavity
Abstract | View details | Full text in PDF | Author Info

The development of the stomatal area wax structure of Scots pine (Pinus sylvestris L.) needles was studied in flushing needles with a scanning electron microscope. The needles were obtained from eleven Finnish plus tree progenies. The needles were taken from trees that were either nearly uninfected or heavily infected by Lophodermella sulcigena (Rostr.) Höhn.

No difference in the early developmental stages of stomatal vax structure were observed between the southern Finnish, central Finnish and northern Finnish progenies. The general structure differed in the stomatal cavity chamber size. The stomatal openings were larger in heavily infected trees than in healthy trees. This might have an influence on the mechanical penetration of the fungal hyphae.

The PDF includes a summary in Finnish.

  • Jalkanen, E-mail: rj@mm.unknown (email)
  • Huttunen, E-mail: sh@mm.unknown
  • Väisänen, E-mail: tv@mm.unknown
article id 5129, category Article
Olavi Luukkanen. (1981). Effects of gibberellins GA4 and GA7 on flowering in Scots pine grafts. Silva Fennica vol. 15 no. 4 article id 5129. https://doi.org/10.14214/sf.a15186
Keywords: Pinus sylvestris; Scots pine; flowering; growth hormones; gibberellic acid; male flowering; female flowering
Abstract | View details | Full text in PDF | Author Info

Ethanolic sprays of GA4 or GA7 on 9-year old Scots pine (Pinus sylvestris L.) grafts, repeated four times during the shoot elongation period, resulted in a statistically significant increase in female flowering one year after the treatment. Of the two compounds, GA4 seemed to be somewhat more efficient, yielding 47 female strobili/100 shoots vs. 36 and 6 strobili/100 shoots in GA7 and control treatments respectively. The mixture of GA4 and GA7 compounds was also applied and seemed to have an effect intermediary to those of the pure compounds. However, due to the limited amounts of material, none of the differences between the gibberellins could be statistically confirmed. Male flowering frequencies were also too low to allow any firm conclusions, but the numerical results suggested that the purified gibberellins may promote male and female flowering in different ways.

The PDF includes a summary in Finnish.

  • Luukkanen, E-mail: ol@mm.unknown (email)
article id 5128, category Article
Paavo J. Ollinmaa. (1981). Eräistä ojitetuilla soilla kasvaneen puun fysikaalisista ominaisuuksista. Silva Fennica vol. 15 no. 3 article id 5128. https://doi.org/10.14214/sf.a15069
English title: Physical properties of wood growing on drained swamps.
Original keywords: kuusi; mänty; ojitetut suot; reaktiopuu; lujuus; puuaineen tiheys; vuosiluston leveys
English keywords: Pinus sylvestris; drained peatlands; Scots pine; density; compressive strength; growth rings; Norway spruce Picea abies; bending strength
Abstract | View details | Full text in PDF | Author Info

The objective of the investigation was to determine the differences between timber grown on a peatland before and after draining, in respect of compressive strength parallel to the grain, static bending strength and density. In addition, the characteristics of boundary zone between the wood formed before, and after the draining with wider growth rings was studied. 41 Scots pine (Pinus sylvestris L.) and 22 Norway spruce (Picea abies (L.) H. Karst.) trees were studied.

The compressive strength of pine usually decreased from the butt end upwards, but no trend was observed in spruce wood. In coniferous trees, wide-ringed wood formed subsequent to draining was slightly lighter than the close-ringed wood produced prior the draining. The density of pine as well as spruce increases as the width of the growth rings decrease up to a certain limit. The strength of the different kinds of wood seems to decrease from the butt end upwards.

In both species, the compressive strength parallel to the grain and the bending strength are lowest in such wood that contains exclusively wide-ringed wood formed subsequent to draining. Also, compressive and bending strength increase with decreasing width of the growth rings. The longitudinal shrinkage of compression wood in spruce was several times that of normal wood, and the bending strength was lower than that of normal wood particularly in spruce. The compressive strength parallel to the grain in dry condition was, however, higher than in normal wood both in pine and spruce.

The PDF includes a summary in English.

  • Ollinmaa, E-mail: po@mm.unknown (email)
article id 5123, category Article
Heljä-Sisko Katainen, Seppo Kellomäki. (1981). Happaman veden vaikutus männyn taimiin. Silva Fennica vol. 15 no. 3 article id 5123. https://doi.org/10.14214/sf.a15064
English title: Effect of foliar application of dilute sulphuric acid on Scots pine seedlings.
Original keywords: mänty; taimet; pituuskasvu; neulasvauriot; fotosynteesi; happamuus; hapan sade
English keywords: Pinus sylvestris; photosynthesis; Scots pine; height growth; acidity; seedlings; needle damages; acid rain
Abstract | View details | Full text in PDF | Author Info

Needle damages, transpiration, photosynthesis and needle and stem height growth of Scots pine (Pinus sylvestris L.) seedlings treated with dilute sulphuric acid were studied. The acidity of the solution was pH 3. Application of a dilute solution of sulphuric acid equivalent to the normal amount of precipitation occurring during the growing season damaged the surface of two-year-old needles but not that of the current-year needles. A reduction in the photosynthetic rate of 10–30% was observed compared with the untreated seedlings. Transpiration of the seedlings was not affected by the treatment. Needle growth and stem height growth of the seedlings growing on a substrate representing poor sandy soil were reduced. Increased needle growth and stem height growth were characteristic for the seedlings growing on substrate representing fertile moraine.

The PDF includes a summary in English.

  • Katainen, E-mail: hk@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
article id 5122, category Article
H. Smolander, J. Kostamo, P. K. Räsänen. (1981). Maan tiiviyden vaikutus männyntaimien haihduntaan ja pituuskasvuun istutuksen jälkeen. Silva Fennica vol. 15 no. 3 article id 5122. https://doi.org/10.14214/sf.a15063
English title: Effect of soil compaction on transpiration and height increment of planted Scots pine seedlings.
Original keywords: mänty; istutus; metsämaa; maan rakenne; tiivistyminen
English keywords: Pinus sylvestris; Scots pine; planting; forest soil; compactment
Abstract | View details | Full text in PDF | Author Info

The effect of soil compaction on transpiration and height increment of Scots pine (Pinus sylvestris L.) seedlings following planting out were investigated in a small-scale pot experiment. Compacted and loosely-packed fine sand and fine-sand moraine were used as the planting substrates. The compacted soils used corresponded to the normal type of soil to be found in tilled forest soils in Finland. The effect of soil compaction on seedling transpiration during water stress was also studied in a separate experiment.

Seedlings planted in compact soil had a higher rate of transpiration than those in loosely-packed soil. The recovery in transpiration, which started halfway through the growing season, was faster, however, in the seedlings planted in loosely-packed soil. Under conditions of water stress, the seedlings planted in compact fine-sand moraine started to reduce the transpiration rate at higher soil moisture values than those planted in loosely-packed soil. No corresponding difference was observed for fine sand. Compaction was not found to affect the overall height growth, but it did at certain time during the growing season.

The PDF includes a summary in English.

  • Smolander, E-mail: hs@mm.unknown (email)
  • Kostamo, E-mail: jk@mm.unknown
  • Räsänen, E-mail: pr@mm.unknown
article id 5116, category Article
Seppo Kellomäki, Pauline Oker-Blom. (1981). Specific needle area of Scots pine and its dependence on light conditions inside the canopy. Silva Fennica vol. 15 no. 2 article id 5116. https://doi.org/10.14214/sf.a15057
Keywords: Pinus sylvestris; needles; Scots pine; crown; crown class; light conditions; needle area
Abstract | View details | Full text in PDF | Author Info

The specific needle area of young Scots pine (Pinus sylvestris L.) showed a substantial within-tree and between-tree variation which was associated with the position of the tree and the position of the whorl as indicated by the prevailing crown and branch illumination. In suppressed trees the values of the specific needle area were three to four times those in dominating trees. A similar morphogenesis was discernible in comparison of the lower and the upper part of the crown. The mean specific needle area value for the whole stand was 184 cm2/g.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Oker-Blom, E-mail: po@mm.unknown
article id 5111, category Article
Seppo Kellomäki. (1981). Effect of the within-stand light conditions on the share of stem, branch and needle growth in a twenty-year-old Scots pine stand. Silva Fennica vol. 15 no. 2 article id 5111. https://doi.org/10.14214/sf.a15052
Keywords: Pinus sylvestris; Scots pine; growth; stand density; branches; stems; light conditions
Abstract | View details | Full text in PDF | Author Info

The share of stem, branch and needle growth was dependent on the within-stand light regime in a young Scots pine (Pinus sylvestris L.) stand. The share of needle growth increased at the expense of stem and branch growth in poor light conditions. In good light condition the share of branch wood increased substantially. The share of stem wood growth was greatest in moderate shading, emphasizing the role of an adequate stand density for growing high-quality timber. The basic density of the stem wood was considerably greater in suppressed trees than in dominating trees. The differences were related to the illumination of the crown system.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
article id 5110, category Article
Helena Lehtiö. (1981). Effect of air pollution on the volatile oil in needles of Scots pine (Pinus sylvestris L.). Silva Fennica vol. 15 no. 2 article id 5110. https://doi.org/10.14214/sf.a15051
Keywords: Pinus sylvestris; needles; Scots pine; needle damages; air pollution; monoterpene composition; volatile oil
Abstract | View details | Full text in PDF | Author Info

The amount of volatile oil and monoterpene composition in Scots pine (Pinus sylvestris L.) needles were studied in trees growing near two factories and in the city of Kuopio, Central Finland. Trees in these locations are exposed principally to sulphur dioxide and fluoride emissions.

The amount of volatile oil increased with increasing injury class in the trees growing near the fertilizer factory. The amounts of volatile oil in trees near the pulp mill differed in the various injury classes. More oil was found in younger needles. The greatest differences in monoterpene composition were in the amounts of camphene, α-pinene, myrcene and tricyclene.

The PDF includes a summary in Finnish.

  • Lehtiö, E-mail: hl@mm.unknown (email)
article id 5092, category Article
Seppo Kellomäki, Markku Kanninen. (1980). Eco-physiological studies on young Scots pine stands. IV. Silva Fennica vol. 14 no. 4 article id 5092. https://doi.org/10.14214/sf.a15033
Keywords: Pinus sylvestris; Scots pine; height growth; radial growth; basic density; crown; photosynthate supply; light conditions
Abstract | View details | Full text in PDF | Author Info

Crown and stem growth of young Scots pines (Pinus sylvestris L.) were studied in relation to photosynthate supply and light condition in a stand. The magnitude of needle and bud formation, and radial and height growth were to a great extent dependent on the photosynthate supply. However, in shaded conditions the growth of each characteristics was greater than expected on the basis of photosynthate supply. In the stem system this was especially apparent for height growth. Consequently, height growth was favoured at the expense of radial growth in shaded conditions. It also appeared that the basic density of wood was negatively related to both tree position and photosynthate supply.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Kanninen, E-mail: mk@mm.unknown
article id 5086, category Article
Jussi Meriluoto. (1980). MCPA- ja 2,4,5-T-herbisidien käyttökelpoisuus taimiston hoidossa. Silva Fennica vol. 14 no. 4 article id 5086. https://doi.org/10.14214/sf.a15027
English title: Applicability of MCPA- and 2,4,5-T-herbicides in sapling stand management.
Original keywords: mänty; koivu; herbisidit; taimikonhoito; haapa; vesakontorjunta
English keywords: Populus tremula; Pinus sylvestris; Betula; Scots pine; herbicides; herbicide; seedling stands; aspen; brushkiller; shrub clearance
Abstract | View details | Full text in PDF | Author Info

The applicability of MCPA- and 2,4,5-T-herbicides for use in the management of sapling stands and the possibilities of carrying out foliar spraying at an earlier date than at precent with smaller doses of the active ingredient were examined in this study. The results were obtained from foliage spraying experiments carried out in Central Finland in summer 1976. MCPA and 2,4,5-T were as effective as each other against deciduous tree species. However, MCPA was slightly more effective against aspen (Populus tremula L.) than 2,4,5-T. The spraying date had no effect on the mortality rate of aspen or birch (Betula pendula Roth and B. pubescens Ehrh.) There were only very slight differences between the results for different dosage levels. The damage caused to Scots pine (Pinus sylvestris L.) was very slight. The temperature conditions prevailing during spraying affected spraying effectiveness in such way that the mortality rate decreased during cold period.

The PDF includes a summary in English.

  • Meriluoto, E-mail: jm@mm.unknown (email)
article id 5081, category Article
Reijo Jokinen. (1980). Metsälannoituksella saatavan kasvunlisäyksen arviointi. Silva Fennica vol. 14 no. 3 article id 5081. https://doi.org/10.14214/sf.a15022
English title: Estimation of growth response achieved through forest fertilization.
Original keywords: kuusi; mänty; lannoitus; typpilannoitus; metsikkötunnukset; kasvunlisäys; pohjapinta-ala
English keywords: Pinus sylvestris; basal area; Norway spruce; fertilization; Picea abies; Scots pine; growth
Abstract | View details | Full text in PDF | Author Info

Dependence of the growth increase given by fertilization on different stand characteristics is examined in this article. The aim was to determine whether the volume growth increase can be accurately determined beforehand when fertilization is carried out on mineral soil sites at a dosage of 120 kg N/ha. The material consisted mostly on of mature stands ready for cutting, a total of 22 Scots pine (Pinus sylvestris L.) and 20 Norway spruce (Picea abies (L.) H. Karst.) stands. Increase in basal area, height quality class and basal area of the stand were found to best explain the increment and its increase in the regression equations calculated for different types of fertilizer and the control level.

The PDF includes a summary in English.

  • Jokinen, E-mail: rj@mm.unknown (email)
article id 5080, category Article
Annikki Mäkelä, Pertti Hari, Seppo Kellomäki. (1980). Eco-physiological studies on young Scots pine stands. III. Silva Fennica vol. 14 no. 3 article id 5080. https://doi.org/10.14214/sf.a15021
Keywords: Pinus sylvestris; biomass; Scots pine; canopy layer; wood formation; needle biomass; photosynthate allocation
Abstract | View details | Full text in PDF | Author Info

The proportions of needle and wood in current-year shoots in crown systems of young Scots pine (Pinus sylvestris L.) trees was studied. The proportion of needles out of the total shoot biomass increased according to the increasing number of the whorl counted from the apex. In the lower part of the crown system the needle biomass of newly-formed shoots was 50–60 fold compared to that of wood and bark biomass. In the upper part of the crown system the same ratio was 1–2. The variation in ratio between needle and wood biomass was whorl-specific and independent of tree class. The magnitude of the ratio was not related to the position of the tree in the stand nor to the prevailing light conditions within the state.

The PDF includes a summary in Finnish.

  • Mäkelä, E-mail: am@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
article id 5079, category Article
Seppo Kellomäki, Pertti Hari, Pirkko Ilonen, Markku Kanninen. (1980). Eco-physiological studies on young Scots pine stands. II. Silva Fennica vol. 14 no. 3 article id 5079. https://doi.org/10.14214/sf.a15020
Keywords: Pinus sylvestris; photosynthesis; Scots pine; stand density; needle biomass; crown class; needle distribution
Abstract | View details | Full text in PDF | Author Info

The technique of double normalizing, i.e. normalizing the relative needle biomass and the length of the living crown system, is applied to the modelling of the distribution of needle biomass in the canopy of young Scots pine (Pinus sylvestris L.) stands. The study based on the parameters of β-function shows that at the individual-tree level, the variance in needle distribution was not closely associated with any tree characteristics. A shift in the point of maximum needle biomass upwards unsuppressed trees was, however, evident. This was associated with an increase in the height of the trees. At the stand level, the stand mean height and stand density had an equal and a rather high potential for explaining the variance in the needle distribution. The normalized crowns are utilized in models for determining light extinction in the crown. A special technique for determining the amount of photosynthates available for growth in a particular tree is presented.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
  • Ilonen, E-mail: pi@mm.unknown
  • Kanninen, E-mail: mk@mm.unknown
article id 5078, category Article
Seppo Kellomäki, Pertti Hari. (1980). Eco-physiological studies on young Scots pine stands. I. Tree class as indicator of needle biomass, illumination and photosynthetic capacity of crown system. Silva Fennica vol. 14 no. 3 article id 5078. https://doi.org/10.14214/sf.a15019
Keywords: Pinus sylvestris; Scots pine; canopy; photosynthetic capacity; needle biomass; tree class
Abstract | View details | Full text in PDF | Author Info

The concept of tree class as indicated by dominant, codominant, intermediate and suppressed trees is analysed using empirical material representing 13 younger Scots pine (Pinus sylvestris L.) stands. The relative needle biomass, i.e. the needle biomass related to the maximum needle biomass in the stand, was closely related to the relative height of the tree and independent of the stand characteristics. Furthermore, the relative illumination of the crown system was related to the relative height of the trees as well as the relative photosynthetic capacity and tree-to-tree variation in growth. When calculated per needle biomass unit it appeared that height growth, radial growth, needle growth and other growth parameters were the highest in the suppressed trees. The suppressed trees thus appear to be more efficient in utilizing available resources than other tree classes. The ecologic significance of the results is discussed.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
article id 5076, category Article
Veikko Koski. (1980). Minimivaatimukset männyn siemenviljelyksille Suomessa. Silva Fennica vol. 14 no. 2 article id 5076. https://doi.org/10.14214/sf.a15017
English title: Minimum requirements for seed orchards of Scots pine in Finland.
Original keywords: mänty; siemenviljelmät; kloonit; siemenviljely; laatuvaatimukset
English keywords: Pinus sylvestris; Scots pine; Finland; seed orchards; clones; requirements
Abstract | View details | Full text in PDF | Author Info

In order to be recorded in the national list of untested seed orchards, set by law, a seed orchard must attain certain objectives. It is impossible to define universal requirements for all categories of seed orchards of all species. The present paper suggests minimum requirements for a clonal region seed orchards of Pinus sylvestris L in Finland. The clonal composition as well as factors influencing on the mating pattern have been given precise numerical threshold values. To be approved the seed orchard must fulfil all the requirements at the same time. The goal is to control the genetic superiority of the forest reproductive material obtained from registered untested seed orchards.

The PDF includes a summary in English.

  • Koski, E-mail: vk@mm.unknown (email)
article id 5071, category Article
Martti Ryynänen. (1980). X-ray radiography of ageing Scots pine seeds. Silva Fennica vol. 14 no. 1 article id 5071. https://doi.org/10.14214/sf.a15012
Keywords: Pinus sylvestris; germination; Scots pine; storage; seeds; quality of seeds; X-ray radiography; X-ray contrast radiography
Abstract | View details | Full text in PDF | Author Info

Soft X-ray radiation (Grenz rays) has been used in the X-ray radiography of seeds. It is based on the principle that the different parts of the seed absorb X-rays to a slightly varying extent. Empty seeds and empty regions in the seeds appears as dark areas on the film. X-ray radiography without staining and X-ray contrast radiography were compared to study the stored seeds of Scots pine (Pinus sylvestris L.). The results were compared with the results of germination in a Jacobsen germinator according to ISTA norms.

Normal X-ray radiography gave too good estimates of germinative capacity of the seeds, and was shown to suit only when it is used to study fully ripe seeds which have recently been collected in an undamaged condition. The results of X-ray contrast radiography when barium chloride was used as the stain, however, followed closely the germination results.

The PDF includes a summary in Finnish.

  • Ryynänen, E-mail: mr@mm.unknown (email)
article id 5070, category Article
Olavi Luukkanen, Stig Johansson. (1980). Flower induction by exogenous plant hormones in Scots pine and Norway spruce grafts. Silva Fennica vol. 14 no. 1 article id 5070. https://doi.org/10.14214/sf.a15011
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; flowering; seed orchards; growth hormones; gibberellin; kloonit
Abstract | View details | Full text in PDF | Author Info

The aim of the present study was to establish whether hormone treatments would promote flowering in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) grafts under Finnish conditions. Also, an attempt was made to test the efficiency of hormones as well as the variation in response among different clones. Six Scots pine and six Norway spruce clones were selected in each seed orchard based on their flowering intensity, and treated with growth hormones (GA, NAA) of different dosages by spraying. Flowering was observed one year after the treatments.

None of the treated or untreated spruce grafts flowered. However, poor flowering in the natural stands indicated that the environmental conditions during the previous years did not favour flowering. On the other hand, a distinct increase in flowering in Scots pine was observed as a result of spraying with hormone solutions. Treatments with gibberellin had a distinct promoting effect both on male and female flowering in the Scots pine grafts, although the responses varied between the different hormones or clones. The relative effect was generally stronger in male flowering.

The PDF includes a summary in Finnish.

  • Luukkanen, E-mail: ol@mm.unknown (email)
  • Johansson, E-mail: sj@mm.unknown
article id 5069, category Article
Jouni Mikola. (1980). The effect of seed size and duration of growth on the height of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) provenances and progenies at the nursery stage. Silva Fennica vol. 14 no. 1 article id 5069. https://doi.org/10.14214/sf.a15010
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; height growth; provenance; seed size; annual growth rhythm
Abstract | View details | Full text in PDF | Author Info

In this paper the connection between seed weight and amount and duration of growth are studied at the progeny level within stands or climatically uniform areas, and at the provenance level within larger geographic areas. The material consists of materials of several experiments in the nursery of Maisala in Southern Finland in 1971–76. The origins of the plant material used in the different experiments ranged from progenies of individual Scots pine (Pinus sylvestris L.) or Norway spruce (Picea abies (L.) H. Karst.) trees to provenance selections covering almost the whole natural range of these species.

The effect of seed weight on plant height is strongest immediately after germination and subsequently decreases steadily, when the genetic growth properties of the plants themselves become effective. The effect is usually visible at least until the end of the 1st growing season. This relationship varies considerably depending on the material studied. The connections between the duration and the amount of height growth also proved to differ according to the nature of genetic variation. In wide selection of provenances, which show clear genetic differentiation in annual growth rhythm. The variation in the duration of growth accounts for most of the differences in total height growth. At the individual and family level or between provenances of a limited area, there seems to be no clear connection between the duration and the amount of growth. It seems that the duration of the annual growing period is a genetic property, which is not affected by seed weight.

The total height alone in 1-year old test material grown in a greenhouse had hardly any value in the forecasting of growth capacity. The growth differences were caused mainly by the variation in seed size and growth rate differences during the growing period.

The PDF includes a summary in Finnish.

  • Mikola, E-mail: jm@mm.unknown (email)
article id 5067, category Article
Veikko Koski. (1980). On the variation of flowering and seed crop in mature stands of Pinus sylvestris L. Silva Fennica vol. 14 no. 1 article id 5067. https://doi.org/10.14214/sf.a15008
Keywords: Pinus sylvestris; Scots pine; flowering; capacity; periodicity; seed crop
Abstract | View details | Full text in PDF | Author Info

The paper discusses the variation of flowering and seed crop of Scots pine (Pinus sylvestris L.) stands based on literature published in Finland. According to the studies, the list of good seed years given by different authors do not completely match, and no essentially new about the periodicity of the seed crop or the causes of variation has been found. The difficulty in classification of the seed crops in different years in different stands and locations can be handled through the concept of capacity. It is suggested in the paper that to be able to compare the occurrence of good flowering and seed years of different stands and localities, a case exceeding 50% of the capacity is described as abundant, and a case exceeding 75% as very heavy.

The PDF includes a summary in Finnish.

  • Koski, E-mail: vk@mm.unknown (email)
article id 5066, category Article
J. P. Efimov. (1980). Some results on the regularities of seed crops in Scots pine seed orchards. Silva Fennica vol. 14 no. 1 article id 5066. https://doi.org/10.14214/sf.a15007
Keywords: Pinus sylvestris; Scots pine; tree breeding; seed orchards; Symposiums; Soviet Union; USSR; seed crop; cone yield
Abstract | View details | Full text in PDF | Author Info

Establishment of seed orchards to produce genetically improved seed started in the USSR in the 1960’s. The aim is that within 10–15 years the total seed production will reach 50% of the seed used. The paper describes seed production in seed orchards of Scots pine (Pinus sylvestris L.) in the forest-steppe of the European part of the USSR. The orchards have been established either by grafting or by planting of seedlings originating from plus trees. The grafts begin flowering relatively early, however, only at the age of 8–10 years seed crops become relatively regular and abundant. The cone yield in young seed orchards have great variability, and the yield of cones varies between clones. Cone yield does not always correlate with a good seed yield. One of the reasons for high amount of empty seeds is the difference in the periods of flowering between the clones.

The seed crops can be improved by establishing optimal conditions for the growth of the trees. Also, when a seed orchard is founded, the peculiarities of the generative activities of the clones and their reactions to changes in the environmental conditions must be taken account by taking an individual and selective measure approach to improvement measures. The orchards can be established with clones for their genetic combining ability and their requirements for the stimulation of seed-bearing.

The PDF includes a summary in Finnish.

  • Efimov, E-mail: je@mm.unknown (email)
article id 5063, category Article
Pirkko Velling. (1980). Variation in the density of wood of different Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst.) origins in provenance tests. Silva Fennica vol. 14 no. 1 article id 5063. https://doi.org/10.14214/sf.a15004
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; basic density; provenience; Symposiums
Abstract | View details | Full text in PDF | Author Info

The study concerned with variations in the density of the wood of different provenances in provenance test series of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) RH. Karst.), established in 1931. Increment cores were collected from 10 sample trees from each sample block. The density of the pine wood was noticeably higher than that of spruce. The basic density was in average 450 kg/m3 for Scots pine, and the variation between different origins was 3–9%, while the average basic density of spruce was under 400 kg/m3 and the variation 3–10%. Statistically significant differences were found between the mean basic densities of different provenances in all sub-experiments for spruce, but only in one pine sub-experiment. However, these differences were not due to the altitude or latitude of the place of the origin. Volume growth seems to be the dominant component in the formation of dry matter yield.

The PDF includes a summary in Finnish.

  • Velling, E-mail: pv@mm.unknown (email)
article id 5056, category Article
Liisa Nylund, Antti Haapanen, Seppo Kellomäki, Markku Nylund. (1980). Radial growth of Scots pine and soil conditions at some camping sites in southern Finland. Silva Fennica vol. 14 no. 1 article id 5056. https://doi.org/10.14214/sf.a14997
Keywords: Pinus sylvestris; Scots pine; ground vegetation; radial growth; trampling; soil compaction; recreation; camping areas
Abstract | View details | Full text in PDF | Author Info

Radial growth of Scots pine (Pinus sylvestris L.) was investigated in seven camping areas located in Southern Finland. Radial growth reduction of 20–40% were found. The magnitude of this reduction was related to the amount of damage in the trees, and the age of the trees. A loss of humus, exposure of the roots and soil compaction were associated with the use of area but not related to the reduction in growth.

The PDF includes a summary in Finnish.

  • Nylund, E-mail: ln@mm.unknown (email)
  • Haapanen, E-mail: ah@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
  • Nylund, E-mail: mn@mm.unknown
article id 5049, category Article
Pirkko Ilonen, Pertti Hari, Markku Kanninen, Seppo Kellomäki. (1979). On distribution of growth in crown system of young Scots pine stands. Silva Fennica vol. 13 no. 4 article id 5049. https://doi.org/10.14214/sf.a14906
Keywords: Pinus sylvestris; light; Scots pine; needle; branching; terminal growth
Abstract | View details | Full text in PDF | Author Info

Branching and terminal growth of lateral shoots and needle growth of Scots pine (Pinus sylvestris L.) is investigated as a function of the whorl’s position and age and prevailing light climate. Number of buds per whorl was linearly and positively related to the whorl’s position and prevailing light climate. The growing whorl’s number counting from the apex was associated with declining bud number. The terminal growth of lateral shoots increased exponentially within the values 0.6–1.0 of the whorls position. Under these values the terminal growth was negligible. The growing whorl’s number indicated curvlinear decrease in shoot growth respectively, and only negligible growth occurred when the whorl’s age exceeded 10 years. The shoot growth was linearly related to the prevailing light climate but differences between dominating and dominated trees were apparent. The distribution of needle growth in the crown system was similar to that of shoot growth.

The PDF includes a summary in Finnish.

  • Ilonen, E-mail: pi@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
  • Kanninen, E-mail: mk@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
article id 5048, category Article
Seppo Kellomäki. (1979). The effect of solar radiation and air temperature on basic density of Scots pine wood. Silva Fennica vol. 13 no. 4 article id 5048. https://doi.org/10.14214/sf.a14905
Keywords: Pinus sylvestris; photosynthesis; Scots pine; temperature; basic density; solar radiation
Abstract | View details | Full text in PDF | Author Info

The effect of solar radiation and air temperature on the basic density of Scots pine (Pinus sylvestris L.) wood has been investigated on the basis of material obtained from the literature. Solar radiation seemed to affect basic density during earlywood formation. Temperature had the greatest effect on basic density  in late summer. The varying effects of radiation and temperature seemed to be associated with the dynamics of the crown system of trees. Especially the capacity of the crown system to produce the amount of photosynthesis needed in tracheid growth is assumed to be of importance in controlling the variation in the basic density of Scots pine wood. Growth of thracheids from the point of view of photosynthate supply is discussed.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
article id 5047, category Article
Pekka Kilkki, Martti Varmola. (1979). A nonlinear simultaneous equation model to determine taper curve. Silva Fennica vol. 13 no. 4 article id 5047. https://doi.org/10.14214/sf.a14904
Keywords: Pinus sylvestris; diameter; mathematical models; taper curve
Abstract | View details | Full text in PDF | Author Info

In the original set of equations derived by regression analysis, relative-height diameters (endogenous variables) are presented as nonlinear functions of the other relative-height diameters and of the height of the tree (an exogenous variable). Any of the original equations can be replaced by an interpolation formula which links a measured diameter to the four closest relative-height diameters. The solution of the simultaneous equation model yields 10 relative-height diameters. Intermediate values are obtained to avoid biases due to the nonlinearity of the simultaneous model equations.

The PDF includes a summary in Finnish.

  • Kilkki, E-mail: pk@mm.unknown (email)
  • Varmola, E-mail: mv@mm.unknown
article id 5033, category Article
Tapani Haapanen, Pertti Hari, Seppo Kellomäki. (1979). Effect of fertilization and thinning on radial growth of Scots pine. Silva Fennica vol. 13 no. 2 article id 5033. https://doi.org/10.14214/sf.a14890
Keywords: Pinus sylvestris; fertilization; thinning; Scots pine; radial growth
Abstract | View details | Full text in PDF | Author Info

The radial growth of Scots pine (Pinus sylvestris L.) stands at the age 30–40 years was measured retrospectively five years after the fertilizing and thinning of the stands. The abrupt effect of fertilizing was culminated 3–4 years after the treatment. The effect of thinning increased throughout the monitoring period. In stands that had been both thinned and fertilized, the effect of thinning was covered almost entirely by the effect of fertilizing, but fertilizing and thinning gave greater response than applying fertilizer or thinning only. 

The PDF includes a summary in Finnish.

  • Haapanen, E-mail: th@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
article id 5026, category Article
Alpo Enivaara. (1979). Pyynikin harjumännikön uudistaminen ja elvyttäminen. Silva Fennica vol. 13 no. 2 article id 5026. https://doi.org/10.14214/sf.a14881
English title: Regeneration and improvement of the Scots pine forest of Pyynikki esker in Southern Finland.
Original keywords: mänty; uudistaminen; seminaarit; maankäyttö; harju; Pyynikki; taajamametsät
English keywords: Pinus sylvestris; regeneration; Scots pine; urban forests; seminar; MAB; natural park
Abstract | View details | Full text in PDF | Author Info

Pyynikki is a unique natural park in the centre of the city of Tampere in Southern Finland. Currently, the forest of Pyynikki is losing its vigour because of aging and environmental factors. In 1977 a policy was designed for the regrowth of Scots pine (Pinus sylvestris L.) forest and improvement of the condition of the trees to avoid the situation that the whole pine forest (34 ha) would be regrown at one time. The period of regrowth of pine forest is 60 years. It is accomplished by cutting small openings, on which 4-year old potted pine saplings are planted. Birch will be planted only on two spots. The aim is that the forest scenery will be maintained as undamaged as possible. The condition of the growing forest will be improved by fertilization and thinning.

This paper was presented in the ‘Man and the Biosphere’ programme project 2 seminar held on August 24–25 1978 in Hyytiälä research station of University of Helsinki.

The PDF includes a summary in English.

  • Enivaara, E-mail: ae@mm.unknown (email)
article id 5022, category Article
Jukka Selander, Paavo Kalo. (1979). Männyn taimen pihkan monoterpeenien vaikutuksista tuhonkestävyyteen tukkimiehentäitä, Hylobius abietis L. ( Coleoptera, Curculionidae) vastaan. Silva Fennica vol. 13 no. 2 article id 5022. https://doi.org/10.14214/sf.a14876
English title: Evaluation of resistance of Scots pine seedlings against the large pine weevil Hylobius abietis L. in relation to their monoterpene composition.
Original keywords: hyönteistuhot; mänty; taimet; tukkimiehentäi; resistenssi; monoterpeeni
English keywords: Pinus sylvestris; Scots pine; Hylobius abietis; seedlings; insect damages; large pine weevil; monoterpenes; insect resistance
Abstract | View details | Full text in PDF | Author Info

The development of Scots pine (Pinus sylvestris L.) seedlings and damage caused by Hylobius abietis L. (Coleoptera, Curculionidae) were studied during a three-year period. Olfactory responses of H. abietis was studied in laboratory with several volatile oils isolated from different kinds of P. sylvestris seedlings. Resistance of seedlings against H. Abietis was evaluated in terms of their monoterpene composition. Three aspects of resistance (preference, antibiosis and tolerance) were evaluated separately. Seedling chemotype was found to be associated with these aspects of host resistance on only minor scale. Discussion was attached to a further search for host resistance arising from other properties and constituents of oleoresin. Height growth of the seedlings recovering from weevil damage was 86–91% compared to healthy seedlings.

The PDF includes a summary in English.

  • Selander, E-mail: js@mm.unknown (email)
  • Kalo, E-mail: pk@mm.unknown
article id 5019, category Article
Pertti Hari, Markku Kanninen, Seppo Kellomäki, Olavi Luukkanen, Paavo Pelkonen, Raimo Salminen, Heikki Smolander. (1979). An automatic system for measurements of gas exchange and environmental factors in a forest stand, with special reference to measuring principles. Silva Fennica vol. 13 no. 1 article id 5019. https://doi.org/10.14214/sf.a14873
Keywords: Pinus sylvestris; photosynthesis; Scots pine; environmental factors; ecology; transpiration; measurement tecniques; forest stand
Abstract | View details | Full text in PDF | Author Info

A system for measuring the net photosynthesis, transpiration and environmental factors within the canopy and ground cover vegetation is described. The system operates continuously throughout the growing season in a young Scots pine (Pinus sylvestris L.) stand. A data-logging unit controls the system and carries out the measurements on the readings of the sensors of photosynthesis, transpiration, light intensity outside the canopy, light climate inside the assimilation chambers, and dry and wet temperatures from selected points. These measurements are shown digitally and automatically punched onto paper tape.

The PDF includes a summary in Finnish.

  • Hari, E-mail: ph@mm.unknown (email)
  • Kanninen, E-mail: mk@mm.unknown
  • Kellomäki, E-mail: sk@mm.unknown
  • Luukkanen, E-mail: ol@mm.unknown
  • Pelkonen, E-mail: pp@mm.unknown
  • Salminen, E-mail: rs@mm.unknown
  • Smolander, E-mail: hs@mm.unknown
article id 5018, category Article
Pertti Laakso, Olli Saikku. (1979). Havaintoja karsituista männyistä sorvatun viilun laadusta. Silva Fennica vol. 13 no. 1 article id 5018. https://doi.org/10.14214/sf.a14872
English title: Observations on the quality of veneer from pruned Scots pine stems.
Original keywords: mänty; pystykarsinta; laatu; vaneri; viilu
English keywords: Pinus sylvestris; Scots pine; pruning; quality; veneer
Abstract | View details | Full text in PDF | Author Info

The material was obtained from Scots pine (Pinus sylvestris L.) stems which were pruned 27 years earlier up to the height of 5–6 m. Rotary cutting was made from 16 pruned stems and 3 unpruned ones. The length of bolts was 70 cm and the thickness of veneer 1.5 mm. The proportion of good quality veneer was 46% in pruned stems and 14% in the others. Veneer with exellent quality was obtained from pruned stems up to the height of tree meters, that is to say a little under the pruning line.
The PDF includes a summary in English.

  • Laakso, E-mail: pl@mm.unknown (email)
  • Saikku, E-mail: os@mm.unknown
article id 5015, category Article
Seppo Kellomäki. (1979). On geoclimatic variation in basic density of Scots pine wood. Silva Fennica vol. 13 no. 1 article id 5015. https://doi.org/10.14214/sf.a14869
Keywords: Pinus sylvestris; Scots pine; climate; temperature; density; rainfall
Abstract | View details | Full text in PDF | Author Info

The effect of temperature and water supply in the basic density of Scots pine (Pinus sylvestris L.) wood was studied on the basis of material obtained from the literature. On a monthly basis, the basic density increased with increasing mean temperature for June, July and August. The rainfall in these months had no detectable effect on the basic density except through the difference between rainfall and evaporation in July. On a yearly basis, the basic density increased with increasing mean temperature, temperature sum and length of growth period. The effect of water supply on the basic density was evident, and a linear relationship between basic density and annual rainfall was detected. The variation in basic density was, however, explained only partly by the chosen factors. Possible reasons for the poor explanatory power have been discussed.

The PDF includes a summary in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
article id 4995, category Article
Pekka Kilkki, Matti Saramäki, Martti Varmola. (1978). A simultaneous equation model to determine taper curve. Silva Fennica vol. 12 no. 2 article id 4995. https://doi.org/10.14214/sf.a14849
Keywords: Pinus sylvestris; Scots pine; diameter; mathematical models; taper curve
Abstract | View details | Full text in PDF | Author Info

A simultaneous equation model to determine taper curve for Scots pine is presented. The diameters at relative heights are endogenous variables and height an exogenous variable. Any equations may be substituted by the measured value of diameter. Solution of the system of equations yields 11 diameters at relative heights. Intermediate values are obtained by interpolation. Interpolation allows the use of diameters measured at absolute heights, too.

The PDF includes a summary in Finnish.

  • Kilkki, E-mail: pk@mm.unknown (email)
  • Saramäki, E-mail: ms@mm.unknown
  • Varmola, E-mail: mv@mm.unknown
article id 4992, category Article
Kari Löyttyniemi, Raimo Hiltunen. (1978). Monoterpenes in Scots pine in relation to browsing preference by moose (Alces alces L.). Silva Fennica vol. 12 no. 2 article id 4992. https://doi.org/10.14214/sf.a14846
Keywords: Pinus sylvestris; Scots pine; Alces alces; moose; moose damages; monoterpenes
Abstract | View details | Full text in PDF | Author Info

Monoterpene hydrocarbon contents of needles in Scots pine (Pinus sylvestris L.) plants both damaged and untouched by the moose (Alces alces L.) were compared in the study. The material was collected in an 8-year-old plantation in Central Finland. Needle samples were taken from the topmost shoot whorl of the plants in the middle of April, 1976. Only minor differences were found between the plant groups. Thus, terpenes in pine presumably play no important role in the browsing preference by moose.

The PDF includes a summary in Finnish.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
  • Hiltunen, E-mail: rh@mm.unknown
article id 4988, category Article
Irja Lehtonen. (1978). Ravinteiden kierto eräässä männikössä. Silva Fennica vol. 12 no. 1 article id 4988. https://doi.org/10.14214/sf.a14842
English title: Nutrient cycle in a Scots pine stand: IV The amount of phytomass and nutrients.
Original keywords: mänty; aluskasvillisuus; ravinteet; biomassa; ravinnekierto; kuiva-aine; runkopuu
English keywords: Pinus sylvestris; biomass; Scots pine; nutrients; ground vegetation; dry matter; stemwood
Abstract | View details | Full text in PDF | Author Info

The distribution of the dry matter and nutrients in Scots pine (Pinus sylvestris L.) tree stock growing on a Vaccinium type site, ground vegetation, and humus were determined in the study. The greatest part of the dry matter in the tree was found in the stemwood. The living branches, roots, bark, needles and dead branches decreasing order of magnitude made up the rest of the biomass. The trees contained over 90%, the field layer vegetation 3% and the bottom layer vegetation 2% of the dry matter in the tree stand. The tree stock contained 86–95% of the total amount nutrients in the stand. The field layer vegetation contained less nutrients than the bottom layer vegetation. Nitrogen, however, was an exception, the amount being approximately the same in both vegetation layers. 

The PDF includes a summary in English.

  • Lehtonen, E-mail: il@mm.unknown (email)
article id 4983, category Article
Satu Huttunen. (1978). The effects of air pollution on provenances of Scots pine and Norway spruce in northern Finland. Silva Fennica vol. 12 no. 1 article id 4983. https://doi.org/10.14214/sf.a14837
Keywords: Pinus sylvestris; Norway spruce; Scots pine; provenance; northern Finland; mortality; seedlings; air pollution; Picea abes
Abstract | View details | Full text in PDF | Author Info

The success of certain Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) provenances from Northern Finland was studied in a tree damage area occasioned by air pollution in the town of Oulu over the period of 1972-76. The pine strains from more northerly and easterly areas and the spruce strains from the immediate vicinity of the site itself were being observed to thrive best. The results point in a similar direction to those of other comparable experiments, except that the mortality rate amongst the saplings was exceptionally high and the proportion of healthy saplings in good condition was found to be unusually low. Structural properties suggestive of resistance to pollution were observable selectively in certain provenances, these including the xeromorphy of needles or thickness of the epidermis. The chief cause of mortality amongst the saplings was found to be the damage inflicted by pollution during the winter, while that arising in the summer months was relatively slight.

The PDF includes a summary in Finnish.

  • Huttunen, E-mail: sh@mm.unknown (email)
article id 4975, category Article
Irja Lehtonen. (1977). Ravinteiden kierto eräässä männikössä. Silva Fennica vol. 11 no. 3 article id 4975. https://doi.org/10.14214/sf.a14826
English title: Nutrient cycle in a Scots pine stand. III Variation in nutrient content of soil, vegetation and precipitation.
Original keywords: mänty; metsikkösadanta; runkovalunta; sademäärä; ravinteet; ravinnekierto
English keywords: Pinus sylvestris; Scots pine; precipitation; stemflow; throughfall; nutrient cycle
Abstract | View details | Full text in PDF | Author Info

The study is part of a project designed to elucidate the nutrient budget of a Scots pine (Pinus sylvestris L.) stand. Results of variation in the nutrient contents were compared with those obtained for the previous growing season.

The potassium and calcium contents varied the greatest in the humus layer. However, in the bottom and field layer vegetation and needles the variation in the nitrogen content was the greatest. The nutrient contents of the needles were affected by the physiological stage of development, needle age and the position in the crown of the tree. The nutrient content of the rainfall increased in the order: free rainfall, throughfall, and stem flow.

The PDF includes a summary in Finnish.

  • Lehtonen, E-mail: il@mm.unknown (email)
article id 4963, category Article
Tapio Lehtiniemi. (1977). Männyn ja kuusen siementen gammasäteilyherkkyyteen vaikuttavista tekijöistä. Silva Fennica vol. 11 no. 1 article id 4963. https://doi.org/10.14214/sf.a14814
English title: Factors affecting gamma-irradiation sensitivity of Scots pine and Norway spruce.
Original keywords: kuusi; mänty; alkuperä; itäminen; siemenet; säteilytys
English keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; Scots pine; progeny; seeds; radiation
Abstract | View details | Full text in PDF | Author Info

This study, comprising three experiments, aims to determine the effect of the geographical origin of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seeds, and the duration of the time lag between the moisture treatment and subsequent irradiation on the gamma-irradiation sensitivity of seeds.

The studies showed that the greater the irradiation dose seeds were subjected to the slower the rate of germination. In general, small radiation doses (250–1,000 rad) had a stimulating effect and the final germination percentage (36–40 days) increased. However, when the level was further increased, the germination percentage decreased. Air-dry and moistened seeds withstood irradiation better than others. In a study with moistened seeds from different geographical sources, pine and spruce seeds from Northern Finland were less able to withstand irradiation than those originating from the south.

The PDF includes a summary in English.

  • Lehtiniemi, E-mail: tl@mm.unknown (email)
article id 4962, category Article
Matti Keltikangas, Kustaa Seppälä. (1977). Ojitusalueiden hieskoivikoiden kasvatus taloudellisena vaihtoehtona. Silva Fennica vol. 11 no. 1 article id 4962. https://doi.org/10.14214/sf.a14813
English title: The economics of growing downy birch stands on drained peatlands in Finland.
Original keywords: kannattavuus; mänty; metsän uudistaminen; ojitetut suot; hieskoivu; uudistamiskustannukset
English keywords: Pinus sylvestris; regeneration; Betula pubescens; Scots pine; downy birch; profitability
Abstract | View details | Full text in PDF | Author Info

The aim of this study was to determine under what conditions and with what premises the growing of Betula pubescens Ehrh. is an economically competitive alternative to the growing of Scots pine (Pinus sylvestris L.) in drained peatlands. The basic material consisted of all drainage projects in Ostrobothnia in Western Finland in 1937–38 and 1957–59, according to the archives of the Central Board of Forestry Tapio, including such areas that were at least moderately fertile and had birch dominated young stands or no tree cover. A total of 202 sample plots were measured.

According to the results, the discounted timber yield of the thinned B. pubescens stands is about 10% greater than that of untreated stands. The removing of birch seedlings and the subsequent growing of fully stocked Scots pine is more profitable than growing B. pubescens stands only if the establishment and subsequent development of the pine stand involve no costs. If the site in question is a fertile open drained peatland, establishment of a pine stand is obviously a better financial proposition than a naturally regenerated birch stand. However, if there is already a fully stocked young birch stand on the site, it is more economical to let it grow using a shortish rotation time.

The PDF includes a summary in English.

  • Keltikangas, E-mail: mk@mm.unknown (email)
  • Seppälä, E-mail: ks@mm.unknown
article id 4960, category Article
Juhani Sarasto, Kustaa Seppälä. (1977). Isojen varpujen hävittämisen vaikutus rämemännikön kehitykseen. Silva Fennica vol. 11 no. 1 article id 4960. https://doi.org/10.14214/sf.a14811
English title: The effect of dwarf-shrub vegetation supression on pine swamp tree stands.
Keywords: Pinus sylvestris; Scots pine; herbicides; shrubs; biological competition; fertilizers; herbisidit
Abstract | View details | Full text in PDF | Author Info

In most pine swamp stands on drained peatlands the dwarf-shrubs are rather important biomass producers. The aim of the experiment was to determine the effect of killing off the dwarf-shrub vegetation on the subsequent development of Scots pine (Pinus sylvestris L.) stand. The dwarf-shrub vegetation was killed by means of herbicides. The results show that by removing competition by the dwarf-shrub vegetation on drained pine swamps, it is possible to pass onto the trees at least some of the freed growth potential.

The PDF includes a summary in Finnish.

  • Sarasto, E-mail: js@mm.unknown (email)
  • Seppälä, E-mail: ks@mm.unknown
article id 4958, category Article
Matti Kärkkäinen. (1977). Araukaarian ja männyn puuaineen ominaisuuksien vertailua. Silva Fennica vol. 11 no. 1 article id 4958. https://doi.org/10.14214/sf.a14809
English title: Comparison of wood properties of Parana pine and Scots pine.
Original keywords: tiheys; mänty; puuaines; pihkatiehyet; araukaaria
English keywords: Pinus sylvestris; Scots pine; wood; density; rays; Araucaria angustifolia; Panama pine
Abstract | View details | Full text in PDF | Author Info

According to the available literature, the appearance of Parana pine (Araucaria angustifolia (Bertol.) Kuntze) wood resembles that of Scots pine (Pinus sylvestris L.). The anatomy is quite different, however. There are no resin canals and fusiform rays with resin canals in Parana pine. They are abundant in Scots pine, however. The basic density of Parana pine is higher. In both species the density increases from the pith outwards, the maximum being reached at the age of 100 years. Compression wood is more common in Parana pine than in Scots pine, and this makes the longitudinal shrinkage of Parana pine greater than that of Scots pine. Otherwise the shrinkage properties do not differ. The mechanical strength is of the same magnitude with the exception of hardness, where Parana pine is superior.

The PDF includes a summary in English.

  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 4956, category Article
Paavo Yli-Vakkuri, Paavo Pelkonen. (1976). Rooting of Scots pine needle fascicles with different growth substances and media. Silva Fennica vol. 10 no. 4 article id 4956. https://doi.org/10.14214/sf.a14802
Keywords: Pinus sylvestris; Scots pine; vegetative propagation; rooting; needle fascicles; Jacobsen’s germination apparatus
Abstract | View details | Full text in PDF | Author Info

Needle fascicles of Scots pine (Pinus sylvestris L.) were rooted in a standard Jacobsen’s germination apparatus. The apparatus was found to be suitable for rooting at least on laboratory scale. The best rooting substrate was living Sphangnum, which remained sufficiently moist in the germination containers throughout the experiments. In a comparison of various growth substrate treatments, the best result was obtained with a combination of IAA (100 mg/l) and thiamine (5 mg/l). The rooting percentage using these growth substances with Sphagnum as the rooting medium was in the first experiment 30 and in the second 48.

The PDF includes a summary in Finnish.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
  • Pelkonen, E-mail: pp@mm.unknown
article id 4954, category Article
Carl Johan Westman. (1976). Fertilization of Scots pine seedlings with different nitrogen fertilizer. Silva Fennica vol. 10 no. 4 article id 4954. https://doi.org/10.14214/sf.a14800
Original keywords: mänty; istutus; kasvu; taimet; lannoitus; kuolleisuus; typpilannoitus; ammoniumsulfaatti
English keywords: Pinus sylvestris; Scots pine; planting; growth; mortality; seedlings; fertilizing; nitrogen fertilizers; ammonium sulphate
Abstract | View details | Full text in PDF | Author Info

The paper describes an attempt to determine whether ammonium, nitrate and urea nitrogen are bound in peat used as a filling material in containerized seedling production, what is the effect of the nutrients on certain chemical properties in the peat, and what is the effect of the nitrogen fertilizers on the primary growth of containerized (paper-pot VH 608) Scots pine (Pinus sylvestris L.) seedlings in connection with planting out. The seedlings were fertilized with ammonium sulphate, potassium nitrate and urea.

The results show that none of the fertilizers used were bound in the peat. The nitrogen content in the above ground part of the seedlings increased clearly. Fertilization with ammonium sulphate resulted in the greatest increment and this increase appears to be permanent. The wintering process was somewhat delayed by the fertilization. The seedling mortality rate for all the treatments has been quite appreciable. However, fertilization particularly with ammonium sulphate on the poorer of the two sites studied has had a positive effect on seedling survival. Furthermore, it appears that fertilizer treatments have decreased growth after planting, but in the case of ammonium sulphate this decrease has changed into a clear growth increment.

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  • Westman, E-mail: cw@mm.unknown (email)
article id 4952, category Article
Irja Lehtonen, Seppo Kellomäki, Carl Johan Westman. (1976). Ravinteiden kierto eräässä männikössä. Silva Fennica vol. 10 no. 4 article id 4952. https://doi.org/10.14214/sf.a14798
English title: Nutrient cycle in a Scots pine stand. II. Amount and quality of precipitation in a Scots pine stand at the pole stage.
Original keywords: mänty; metsikkösadanta; runkovalunta; sademäärä; ravinnekierto; happamuus
English keywords: Pinus sylvestris; Scots pine; precipitation; stemflow; throughfall; acidity; nutrient budget
Abstract | View details | Full text in PDF | Author Info

This study forms part of a project designed to elucidate the total nutrient budget of a Scots pine (Pinus sylvestris L.) stand in Central Finland during the 1974 growing period. Precipitation has been divided up into precipitation, throughfall and stemflow.

The acidity of the rainwater was found to increase in the order – Precipitation, throughfall and stemflow. The electrolyte content of the rain water from throughfall and stemflow was higher than that of precipitation. The nutrient contents of precipitation were rather low. Throughfall and stemflow were found to leach some nutrient from the trees. This was most clear in the case of potassium. The total amounts of nutrients reaching the ground in throughfall were found to be smaller than those in precipitation. On the other hand, the amounts of potassium, calcium and magnesium in stemflow were clearly greater than those in precipitation.

The PDF includes a summary in English.

  • Lehtonen, E-mail: il@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Westman, E-mail: cw@mm.unknown
article id 4946, category Article
I. Lehtonen, S. Kellomäki, C. J. Westman. (1976). Ravinteiden kierto eräässä männikössä. Silva Fennica vol. 10 no. 3 article id 4946. https://doi.org/10.14214/sf.a14792
English title: Nutrient cycle in a Scots pine stand I. Seasonal variation in nutrient content of vegetation and soil.
Original keywords: mänty; metsäekologia; neulaset; aluskasvillisuus; ravinnekierto; ravinnepitoisuus; maa; kasvukausi
English keywords: Pinus sylvestris; needles; Scots pine; ground vegetation; soil; soluble nutrients
Abstract | View details | Full text in PDF | Author Info

The paper deals with variation in the nitrogen, phosphorus, potassium, calcium and magnesium content of vegetation and soil of young Scots pine (Pinus sylvestris L.) stand of Vaccinium site type situated in Central Finland. The material consists of sequential samples representing soil, ground vegetation and trees taken during summer 1974.

The amount of soluble nutrients in the humus layer decreased in June when maximum growth of trees and dwarf shrubs occurred. The nutrient content of this layer subsequently began to increase towards the end of the growing period.

The variation in the nutrient content of the bottom and ground layers followed a similar pattern. Nitrogen content increases at the beginning of the summer. After this phase it started to decrease and reached its lowest values by the end of growing period. Phosphorus and potassium content increased throughout the growing period.

The nutrient content of the needles and wood were positively correlated with tree height and negatively with the age of material. The highest values for the nutrient content were for new cells.

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  • Lehtonen, E-mail: il@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Westman, E-mail: cw@mm.unknown
article id 4940, category Article
Paavo Pelkonen, Heikki Smolander. (1976). Männyn kaasunvaihdon elpyminen talvilevon keskeytyessä. Silva Fennica vol. 10 no. 2 article id 4940. https://doi.org/10.14214/sf.a14786
English title: Increase in gas exchange rate in Scots pine by terminating the winter rest period.
Original keywords: mänty; fotosynteesi; aineenvaihdunta; haihdunta; talvilepo
English keywords: Pinus sylvestris; Scots pine; net photosynthesis; winter dormancy; transpiration
Abstract | View details | Full text in PDF | Author Info

The activation of CO2 exchange was monitored in two Scots pine (Pinus sylvestris L.) seedlings transferred from the field to the laboratory in December. Gas exchange was monitored by an URAS I infrared gas analyser in a so-called open IRGA-system with trap type chambers. Transpiration was also measured at the same time by weighing the potted seedlings twice a day. The measuring period lasted eleven days. During the period, the level of both transpiration and net photosynthesis increased about ten times. Furthermore, it was found that the level of photosynthesis at high temperatures was relatively lower at the beginning than at the end of the measuring period.

The PDF includes a summary in English.

  • Pelkonen, E-mail: pp@mm.unknown (email)
  • Smolander, E-mail: hs@mm.unknown
article id 4938, category Article
Matti Kärkkäinen. (1976). Mäntyrunkojen ydinsäteiden korkeus ja leveys. Silva Fennica vol. 10 no. 2 article id 4938. https://doi.org/10.14214/sf.a14783
English title: Height and width of rays in Scots pine stems.
Original keywords: mänty; ydinsäteet; pihkatiehyet; puuaine; puun rakenne
English keywords: Pinus sylvestris; Scots pine; xylem; fusiform rays; uniseriate rays; rays
Abstract | View details | Full text in PDF | Author Info

In this study the width and height of 1,588 uniseriate and 454 fusiform rays were measured from tangential sections of four Scots pine (Pinus sylvestris L.) trunks. The samples represented various height levels and distances from the pith. The average width of the uniseriate rays was 19.7 μm and that of the fusiform rays, 51.9 μm. The average height of the uniseriate rays was 215.7 μm and that of the fusiform rays 406.2 μm. Due to this difference in height, it may be possible to develop an automatic system for distinguishing between uniseriate end fusiform rays on the basis of their height.

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  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 4930, category Article
Tapio Lehtiniemi. (1976). Ionisoivan säteilyn vaikutus varastokuivien ja liotettujen metsäpuiden siementen idäntään ja taimien alkukehitykseen. Silva Fennica vol. 10 no. 1 article id 4930. https://doi.org/10.14214/sf.a14772
English title: Effect of ionizing radiation on the germination of storage-dry and soaked forest tree seeds and on the initial development of seedlings.
Original keywords: metsänjalostus; itäminen; siemenet; säteilytys; mutaatiot
English keywords: Pinus sylvestris; Betula pendula; Picea abies; germination; Betula pubescens; Alnus glutinosa; Alnus incana; seeds; forest tree breeding; radiation; mutations
Abstract | View details | Full text in PDF | Author Info

The study was carried out in order to find out the changes taking place in germination of seeds in certain tree species as a function of gamma irradiation, the height growth of the seedlings produced and the types of phenotypic mutants possibly found in the generation that had received radiation. The tree species studied were Pinus sylvestris L., Picea abies (L.) H. Karst., Betula verrucosa (Betula pendula Roth), B. Pubescens Ehrh., Alnus glutinosa (L.) Gaertn. and Alnus incana (L.) Moench.

Soaked seeds that had received a rather small dose of radiation germinated usually better than storage-dry seeds, B. pubescens being an exception. The damages observed in germination, height growth and the relative number of mutants were greater the higher the irradiation doses. The LD50 dose (germination, 28 days) was as follows in the case of the different tree species (storage dry/soaked): P. Sylvestris 1,500-2,000/2500-3,000, P. abies 1,000-1,500/4,000-4,500, B. pendula 9,500-10,000/7,000-7,500, B. pubescens >10,000/7,500-8,000 and A. Glutinosa 10,000/8,500-9,000 rad. Mass production of different mutants of deciduous trees for ornamental purposes, for example, appears to be easy using gamma-irradiation. On the other hand, the possibility of increasing tree growth remains open for further study.

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  • Lehtiniemi, E-mail: tl@mm.unknown (email)
article id 4925, category Article
Matti Kärkkäinen. (1975). Pohjoissuomalaisten mäntytukkien soikeus. Silva Fennica vol. 9 no. 4 article id 4925. https://doi.org/10.14214/sf.a14767
English title: Ovalness of Scots pine logs in Northern Finland.
Original keywords: Pohjois-Suomi; mänty; puutavaranmittaus; läpimitta; sahatukki
English keywords: Pinus sylvestris; Scots pine; saw logs; northern Finland; diameter; timber scaling
Abstract | View details | Full text in PDF | Author Info

The material of this study consists of 1,080 Scots pine (Pinus sylvestris L.) saw logs measures in two saw mills in Northern Finland. The largest and the smallest top-diameter of each log was measured under bark. According to the results, the ovalness was rather small, 1 mm or 4.9% on average. On the other hand, only 14.3% of all logs showed a diameter difference smaller than 2%. The ovalness was larger than 10% in 5.8% of all logs.

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  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 4924, category Article
Teklé Kapustinskaité. (1975). Puuston kasvu ja turpeen tuhkapitoisuus ojitetuilla soilla. Silva Fennica vol. 9 no. 3 article id 4924. https://doi.org/10.14214/sf.a14766
English title: Ash content of peatland soils and stand growth in connection with drainage.
Original keywords: kuusi; mänty; ravinteisuus; puulajit; turvemaat; ojitetut suot; pituuskasvu; rauduskoivu; tervaleppä; Liettua; tuhkapitoisuus; hieskoivu; metsäsaarni
English keywords: Pinus sylvestris; Norway spruce; birch; Betula pendula; Picea abies; Betula pubescens; drained peatlands; Scots pine; height growth; tree species; Alnus glutinosa; alder; ash content; fertility; Fraxinus exelsior; ash; Lithuania
Abstract | View details | Full text in PDF | Author Info

The ash content has been found to correlate with the fertility of peatlands. Relationship between height of 80-year-old stands and ash content of peat in topmost 30 cm layer was examined in Lithuanian conditions. On drained peatlands with ash content of peat from 3% to 8% pine stands increase in height. Ash content of peat being about 7% Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands on drained sites are found to be of equal height. Ash content of peat more than 8–9% has no significant effect on growth of pine or spruce stands. Birch (Betula verrucosa (B. Pendula Roth.) and Betula pubescens Erhrh.), stands are less sensitive to ash content of peat compared with other species. Black alder (Alnus glutinosa L. Gaertn.) stands occurred in sites with ash content of peat more than 8–10%. The height of the stands become equal both in drained and undrained sites in the cases where ash content of peat is about 16–18%. Ash (Fraxinus exelsior L.) stands attain high productivity on drained sites with ash content of peat about 20%.

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  • Kapustinskaité, E-mail: tk@mm.unknown (email)
article id 4920, category Article
Peitsa Mikola. (1975). Turvetuotannosta vapautuvan maan metsittäminen. Silva Fennica vol. 9 no. 2 article id 4920. https://doi.org/10.14214/sf.a14776
English title: Afforestation of bogs after industrial exploitation of peat.
Original keywords: mänty; metsitys; lannoitus; suojapuusto; turvetuotanto; jälkikäyttö; tuhka; tervaleppä; suonpohja
English keywords: Pinus sylvestris; fertilization; afforestation; Scots pine; Alnus glutinosa; alder; peat production; after-use; ash
Abstract | View details | Full text in PDF | Author Info

Peat industry is rapidly expanding in Finland. Consequently, during next decades peat will be removed from thousands of hectares. Because timber production probably is the most rational use of this area after the peat production has ended, some experiments of afforestation of such areas have already been conducted. This article reports results of two experiments which were started in Kihniö, Western Finland, in 1953 and 1964.

In the first experiment fertilization with wood ash proved very effective whereas seeding and planting without fertilization resulted in almost complete failure. In the second experiment, interplanting with grey alder (Alnus glutinosa L. Gaertn.) greatly promoted the growth of Scots pine (Pinus sylvestris L.). The effect of slight fertilization lasted a few years only. The reasons for the remarkable effect of alder need further research. Although alder is known as a nitrogen-fixing plant, its beneficial effect was most clearly seen in the K and P contents of pine needles. Inoculation with mycorrhizal fungi was beneficial but not necessary. Experiments hitherto show that afforestation of bogs after peat removal is possible although some additional measures like fertilization or interplanting with alder may be needed.

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  • Mikola, E-mail: pm@mm.unknown (email)
article id 4908, category Article
Juhani Päivänen. (1974). Sarkaleveyden ja naveroinnin vaikutus pohjavesipinnan syvyyteen ja männyntaimiston kehitykseen lyhytkortisella nevalla. Silva Fennica vol. 8 no. 4 article id 4908. https://doi.org/10.14214/sf.a14752
English title: The effect of ditch spacing and furrowing on depth of ground water table and on development of a Scots pine plantation on small-sedge bog.
Original keywords: mänty; ojitetut suot; avosuot; pituuskasvu; sarkaleveys; naverointi; kuivatussyvyys; kuivatusteho
English keywords: Pinus sylvestris; drained peatlands; Scots pine; height growth; seedlings; open peatlands; drainage effect; ground water table; ditch spacing; furrowing
Abstract | View details | Full text in PDF | Author Info

The paper describes the results obtained from an investigation into the effect of ditch spacing, ditch depth and furrowing on ground water table and on development of a Scots pine (Pinus sylvestris L.) plantation on open small-sedge bog in Central Finland (60° 50’ N; 24° 20’ E), drained in 1967. The area was planted in 1968 with 2+1 Scots pine transplants, and fertilized with Y fertilizer for peat soils. The seedlings were measured in 1972.

The depth of the ground water table was greater, the narrower the ditch spacing. The water furrows shortened the duration of the high ground water and lowered the ground water table particularly in the case of ineffective drainage. The narrower the ditch spacing within the blocks, the higher were the young trees. On the other hand, the differences in the height of the trees between the ditch spacings were eliminated by the effect of the furrows.

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  • Päivänen, E-mail: jp@mm.unknown (email)
article id 4904, category Article
Sirkka Kupila-Ahvenniemi, Sirkka Hankonen, Seppo Sivonen. (1974). Kokeita röntgenmikroanalyysimenetelmän käyttökelpoisuudesta eräiden alkuaineiden määrityksessä männyn silmuissa. Silva Fennica vol. 8 no. 3 article id 4904. https://doi.org/10.14214/sf.a14748
English title: Experiments on the determination of certain elements in the buds of Scots pine by means of the electron probe x-ray microanalysis.
Original keywords: mänty; menetelmät; silmut; röntgenmikroanalyysi; alkuaineanalyysi
English keywords: Pinus sylvestris; Scots pine; methods; buds; electron probe X-ray microanalysis; elementary analysis
Abstract | View details | Full text in PDF | Author Info

An electron probe X-ray microanalyser was used to study the occurrence of phosphorus, sulphur and calcium in the bud apices of dormant Scots pine (Pinus sylvestris L.). The material was collected during the winter months (November–February), fixed in Carnoy’s fluid, dehydrated, and mounted in paraffin wax. Of the 10 μm longitudinal section, the ones containing the middle portion of the apices were glued to the specimen supports and vacuum coated with aluminium. Three parallel line analysis were run over the corpus and the uppermost portion of the pith. Results obtained so far suggest that no marked changes occur in the position and level of the three elements during the study period.

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  • Kupila-Ahvenniemi, E-mail: sk@mm.unknown (email)
  • Hankonen, E-mail: sh@mm.unknown
  • Sivonen, E-mail: ss@mm.unknown
article id 4903, category Article
Olavi Luukkanen. (1974). Esikokeita kinetiinin vaikutuksesta männyn hypokotyylien kallus- ja juurimuodostukseen. Silva Fennica vol. 8 no. 2 article id 4903. https://doi.org/10.14214/sf.a14747
English title: Effect of kinetin on the formation of callus and roots in hypocotyls of Scots pine; preliminary experiments.
Original keywords: mänty; sirkkataimi; solukkoviljely; kinetiini; IAA; kallus; juurimuodostus; hypokotyyli
English keywords: Pinus sylvestris; Scots pine; tissueculture; germlings; hypocotyls; callus; root formation; kinetin; IAA
Abstract | View details | Full text in PDF | Author Info

After 64 days of aseptic culture, germlings of Pinus Syvestris L. were cut at the middle of the hypocotyl and above the root. The upper and lower halves of the hypocotyls were transferred onto agar medium RM-196 of Linsmaier & Skoog (1964) including 2 mg/l IAA and 0.1, 1 or 10 mg/l kinetin, one or both halves being put in each vial. Callus growth and root formation was observed after 55 days.

The lower ends of basally cut seedlings generally formed callus tissue and 20% of them also formed roots from this callus. No roots and less callus growth were observed in the lower hypocotyle halves excised at both ends. In the latter hypocotyles callus growth was promoted by the presence in the same vial of a basally excised germling, including cotyledons and plumule. Increasing amounts of kinetin slightly enhanced callus formation of basally excised germlings but seemed to inhibit callus growth in hypocotyls excised at both ends and placed alone on the growth medium. The total amount of callus was greatest in hypocotyls which included intact cotyledons and plumule.

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  • Luukkanen, E-mail: ol@mm.unknown (email)
article id 4899, category Article
Matti Kärkkäinen. (1974). Näkökohta tyvi- ja latvaläpimitan keskiarvoon perustuvasta mäntypölkkyjen kuutioinnista. Silva Fennica vol. 8 no. 2 article id 4899. https://doi.org/10.14214/sf.a14743
English title: Note on the volume based on the mean of butt and top diameters of Scots pine bolts.
Original keywords: kuitupuu; mänty; puutavaranmittaus; kapeneminen; tyviläpimitta; latvaläpimitta; kiintotilavuus
English keywords: Pinus sylvestris; Scots pine; pulpwood; timber scaling; tapering; butt diameter; top diameter; volume determination
Abstract | View details | Full text in PDF | Author Info

In this paper the use of butt and top diameters of pulpwood bolts for volume determination is analysed. The study is based on the taper data of Scots pine (Pinus sylvestris L.) stems. According to the results, the use of the mean of butt and top diameters in the volume determination under Finnish condition causes a positive error in small stems. If the stems are so big that the butt portions of the stems can be used as saw logs, the remaining top bolts, used as pulpwood, are estimated to be smaller than they are in reality. Accordingly, there is a negative error.

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  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 4897, category Article
A. V. Chudnyi. (1974). Metsäpuiden populaatiorakenteen tutkimusmenetelmistä. Silva Fennica vol. 8 no. 1 article id 4897. https://doi.org/10.14214/sf.a14741
English title: Investigation methods in forest tree population studies.
Original keywords: mänty; metsänjalostus; taudinkestävyys; männyntyvitervastauti; Neuvostoliitto; terpeenit
English keywords: Pinus sylvestris; Scots pine; tree breeding; Heterobasidion annosum; disease resistance; terpenes; Soviet Union
Abstract | View details | Full text in PDF | Author Info

From the tree breeder’s point of view, an investigation of the chemical compounds in a tree population is worthwhile, if sufficiently high correlations exist between the chemical composition and any economical important characteristics. In Scots pine (Pinus sylvestris L.) populations, such a correlation seems to exist between a high α-pinene and a low Δ3-carene content on the one hand, and the poor resistance to Fomitopsis annosa Fr. (now Heterobasidion annosum (Fr.) Bref.) but a rapid development during the first half of the life cycle on the other hand. Detailed investigation on the terpene contents in pine populations were conducted at 121 locations throughout the Soviet Union. As a result, the range of this species was divided into zones, each of which was characterized by a distinct terpene composition pattern. In continuing selection and breeding work, the terpene contents are being used as indicators when the variation of economically important characteristics of Scots pine populations is studied.

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  • Chudnyi, E-mail: ac@mm.unknown (email)
article id 4889, category Article
Tapio Lehtiniemi. (1973). Turvepuristeet ja männyn kylvö. Silva Fennica vol. 7 no. 4 article id 4889. https://doi.org/10.14214/sf.a14727
English title: Use of peat briquettes in seeding of Scots pine.
Original keywords: kylvö; mänty; itäminen; kasvualustat; turve; turvebriketti; vakoruutukylvö
English keywords: Pinus sylvestris; germination; Scots pine; peat; sowing; seeding; band-sowing
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to assess, through field experiments, the possibilities of using peat briquettes in the seeding of Scots pine (Pinus sylvestris L.) in Southern Finland. The briquettes were dug into the soil in the middle of patches of mineral soil. The seeds were covered by a 2-5 mm layer of mineral soil. The seedings were inventoried in the three following autumns.

According to the results, the briquettes were clearly inferior to the control, which was ordinary drill seeding. This was mainly due to the fact that no rain was received after the seeding, and that the third summer from seeding was extremely dry. Abundant germination was observed during the second summer after seeding in both briquette seeding and the control. During more rainy summers the result might have been better.

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  • Lehtiniemi, E-mail: tl@mm.unknown (email)
article id 4888, category Article
Olavi Luukkanen. (1973). Havaintoja kuusen vapaapölytysjälkeläistöjen ja männyn metsikköalkuperien CO2-aineenvaihdunnasta. Silva Fennica vol. 7 no. 4 article id 4888. https://doi.org/10.14214/sf.a14726
English title: Observations on CO2 exchange in open pollinated progenies of Norway spruce and provenances of Scots pine.
Original keywords: kuusi; mänty; metsänjalostus; pluspuu; fotosynteesi; geneettinen muuntelu; pimeähengitys; yhteyttämisteho
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; tree breeding; photosynthesis capacity; genetic variance; dark respiration
Abstract | View details | Full text in PDF | Author Info

Photosynthesis and dark respiration in five families of autochtonous Norway spruce (Picea abies (L.) H. Karst.) and in seedlings from twenty Finnish stands of Scots pine (Pinus sylvestris L.) were investigated in constant environmental conditions. Values of CO2 exchange were compared with the height growth and weight of seedlings in Norway spruce and with the weight alone in Scots pine. No statistically significant differences were found in CO2 exchange among progenies or stands. Photosynthetic efficiency and photosynthetic capacity showed a positive correlation both in spruce and in pine. Growth and net photosynthetic capacity were linearly and positively correlated in pine. Spruce and a higher light compensation point than pine. The use of an open IRGA system with several simultaneous measurements and the trap-type cuvette construction in genetic work are discussed.

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  • Luukkanen, E-mail: ol@mm.unknown (email)
article id 4881, category Article
Juhani Päivänen. (1973). Harvennuksen vaikutus lumi- ja routasuhteisiin nuoressa turvemaan männikössä. Silva Fennica vol. 7 no. 2 article id 4881. https://doi.org/10.14214/sf.a14717
English title: The effect of thinning on the snow cover and soil frost conditions in a young Scots pine stand on drained peatland.
Original keywords: mänty; harvennushakkuu; turvemaat; ojitetut suot; lumi; lumen syvyys; routa; lumen vesiarvo
English keywords: Pinus sylvestris; soil frost; thinning; drained peatlands; Scots pine; snow cover; depth of snow; water equivalent of snow
Abstract | View details | Full text in PDF | Author Info

The paper describes the results obtained from an investigation into the effect of thinning of different intensity and fertilization on the depth and water equivalent of the snow cover as well as on the depth of the soil frost in a young Scots pine (Pinus sylvestris L.) stand growing on drained peatland in Central Finland. Thinnings and fertilization was carried out in 1968, and the snow cover was followed in the winters 1970/71 and 1971/72.

Only extremely heavy thinnings (60% of the volume) seemed to increase the depth and water equivalent of the snow cover. The indirect effect of fertilization on the snow cover was insignificant. In the clear-cut sample plot of the study, soil frost was either not found at all or the depths of the frozen soil layer was smaller than in the other plots. When deciding the silvicultural measures to be taken in the case of tree stands growing on drained peatlands, there seems to be reason to avoid radical thinnings. Otherwise, the favourable influence of the trees on a site on its water relationships will be diminished.

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  • Päivänen, E-mail: jp@mm.unknown (email)
article id 4879, category Article
Matti Kärkkäinen. (1973). Mäntyrunkojen ydinsäteiden määrä ja koko. Silva Fennica vol. 7 no. 2 article id 4879. https://doi.org/10.14214/sf.a14713
English title: Amount and size of rays in Scots pine stems.
Original keywords: mänty; runko; puuaines; ydinsäteet; pihkatiehyet; pihka
English keywords: Pinus sylvestris; Scots pine; structure of wood; fusiform rays; uniseriate rays; resin canal; pitch
Abstract | View details | Full text in PDF | Author Info

The material consists of four Scots pine (Pinus sylvestris L.) stems from which 757 samples were taken from various heights and distances from the pith. According to the results, the number of rays and their sizes are greater at the stump level than higher up in the stem. The size increases, and the number decreases on moving from the pith outwards. However, there are differences between stems as regards the variation model. The ratio between the number of fusiform rays and that of uniseriate rays seems to be lower than anticipated earlier, about 1:40–1:50. The average proportion of ray volume varied from 5.6% to 7.3%.

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  • Kärkkäinen, E-mail: mk@mm.unknown (email)
article id 4877, category Article
Pertti Laatikainen. (1973). Jyrsinturve ja kuorihumus männyn kylvötaimien kasvualustoina muovihuoneessa. Silva Fennica vol. 7 no. 1 article id 4877. https://doi.org/10.14214/sf.a14707
English title: Milled peat and milled bark as substrate for Scots pine seedlings in greenhouses.
Original keywords: mänty; taimitarha; taimituotanto; lannoitus; kasvualustat; kasvihuoneviljely; kuorihumus; turve
English keywords: Pinus sylvestris; nursery; Scots pine; substrate; tree seedlings; greenhouse cultivation; milled peat; milled bark
Abstract | View details | Full text in PDF | Author Info

The purpose of this study was to compare the development of Scots pine (Pinus sylvestris L.) seedlings sown on substrates off milled peat and milled bark. Mille peat, ordinary milled bark, milled inner bark waste, and a mixture of milled peat and milled bark in the ratio of 1:1, were all compared in the plastic greenhouse. In addition, two fertilization applications were used with milled park: ordinary surface fertilization and double surface fertilization. The germination and development were measured twice during the summer.

It is concluded that milled bark seems to be a rather useful substrate for use in plastic greenhouses, as long as its special requirements are taken into consideration. In the first measurement, there were no differences between the treatments, in the second measurements seedlings growing on a mixture of peat and bark were slightly more developed than the others. Growth of the seedlings was slightly better in ordinary milled bark. Double surface fertilization increased disease and mortality compared to ordinary fertilization.

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  • Laatikainen, E-mail: pl@mm.unknown (email)
article id 4869, category Article
Ole Oskarsson, P. M. A. Tigerstedt. (1972). Metsänjalostuksen mahdollisuudet II. Silva Fennica vol. 6 no. 3 article id 4869. https://doi.org/10.14214/sf.a14672
English title: The possibilities in forest tree breeding II. Selection differences and genetic gains in selected seed stands of Scots pine.
Original keywords: mänty; metsänjalostus; tilavuuskasvu; valintahyöty; siemenkeräysmetsät; fenotyyppi; kuutiokasvu
English keywords: Pinus sylvestris; Scots pine; volume growth; genetic gain; forest tree breeding; seed stands; phenotype
Abstract | View details | Full text in PDF | Author Info

The aim of this study was to estimate the genetic gain of volume growth in Scots pine (Pinus sylvestris L.) selected seed stands. To obtain highest possible accuracy, the estimations are based on a large statistical material comprising 197 separate seed stands. It is concluded that the genetic gain of volume growth ranges between 7.4–15.0%. Unwanted pollen contaminations may, however, in the worst case halve this genetic gain.

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  • Oskarsson, E-mail: oo@mm.unknown (email)
  • Tigerstedt, E-mail: pt@mm.unknown
article id 4868, category Article
Mikko Tormilainen. (1972). Havaintoja Oitin siemenviljelyksen mäntykloonien kukinnasta ja käpysadosta. Silva Fennica vol. 6 no. 2 article id 4868. https://doi.org/10.14214/sf.a14671
English title: Studies of flowering and cone crop in a seed orchard of Scots pine.
Original keywords: Etelä-Suomi; mänty; kloonit; siemenviljelmä; siemenviljely; kukinta; käpysato; geneettinen vaihtelu
English keywords: Pinus sylvestris; Scots pine; flowering; genetic variation; seed orchards; clones; Southern Finland; cone production
Abstract | View details | Full text in PDF | Author Info

Male and female flowering, cone crop, and some vegetative characteristics were studied in grafts 10 to 16 years of age in a clonal seed orchard of Scots pine (Pinus sylvestris L.). Genetic variation was found between clones in flowering as well as in cone production. Clone evaluation resulted in similar classifications of clones in different years. A regression analysis showed that crown size clearly increased but previous height growth slightly decreased flowering and cone production. The percentage of pollinated female strobili did not differ between clones.

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  • Tormilainen, E-mail: mt@mm.unknown (email)
article id 4860, category Article
Pentti Erjala, Jussi Saramäki. (1972). Astiakoemenetelmä suotyyppien lannoitustarpeen määrityksessä. Silva Fennica vol. 6 no. 1 article id 4860. https://doi.org/10.14214/sf.a14663
English title: Determination of the need for fertilizer application of drained peat soils with the pot method.
Original keywords: mänty; suotyyppi; turvemaat; lannoitus; ojitetut suot; ravinteiden puute; lannoitustarve
English keywords: Pinus sylvestris; fertilization; drained peatlands; Scots pine; nutrient deficiency; peatland type; need for fertilizers
Abstract | View details | Full text in PDF | Author Info

The possibilities of using a pot method to determine the need for fertilizer application were studied. Seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) were grown in peat samples that had cylindrical shape with a diameter of 25 cm and height of 35 cm. The samples represented three different peatland types, and were fertilized with two levels of phosphorus, potash and nitrogen. Two transplants were planted per pot. The development of the seedlings was followed for three years.

Phosphorus seemed to be of greatest importance for the growth of the seedlings, but nitrogen was also required in the poorest peatland type. Potash did not give statistically significant results. NPK application gave the best response. The usability of the method was studied by following the development of the roots. It seemed that the diameter of the pots was too small and restricted the growth of the root systems.

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  • Erjala, E-mail: pe@mm.unknown (email)
  • Saramäki, E-mail: js@mm.unknown
article id 4859, category Article
Eljas Pohtila. (1972). Istutuskuoppaan annetun kuparihienofosfaatin vaikutus männyn ja kuusen taimien elossapysymiseen ja pituuskasvuun eräällä kulotetulla ja auratulla uudistusalalla Koillis-Suomessa. Silva Fennica vol. 6 no. 1 article id 4859. https://doi.org/10.14214/sf.a14662
English title: Effect of fine-grounded copper rock phosphate placed in the planting hole on the survival and height growth of Scots pine and Norway spruce in a burnt and furrowed reforestation are in northeast Finland.
Original keywords: kuusi; mänty; metsänviljely; taimet; lannoitus; kuolleisuus; pituuskasvu; fosforilannoitus
English keywords: Pinus sylvestris; Norway spruce; fertilization; Picea abies; Scots pine; height growth; planting; phosphorus; mortality; copper; seedlings
Abstract | View details | Full text in PDF | Author Info

The paper describes the results of a fertilization experiment, in which transplants of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) were fertilized with various doses of fine-ground copper rock phosphate (33% P2O5, 4% Cu) placed direct in the planting hole. The experiment was made in northeast Finland on a clear-cut, burnt-over and furrowed moraine heath. The fertilization increased especially the survival and condition of the Scots pines and increased to some extent also the height growth of the plants. The spruce survived better than the pines.

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  • Pohtila, E-mail: ep@mm.unknown (email)
article id 4856, category Article
Pekka Rautiainen. (1971). Ympäristö- ja perintötekijöiden vaikutus männyn ilmiasuun Pohjois-Karjalan piirimetsälautakunnan siemenviljelyksessä Tohmajärvellä. Silva Fennica vol. 5 no. 4 article id 4856. https://doi.org/10.14214/sf.a14658
English title: The effect of environmental and genetical factors on the phenotype of Scots pine in a seed orchard in North Karelia.
Original keywords: mänty; oksikkuus; Suomi; periytyvyys; pituuskasvu; fenotyppi; heritabiliteetti; siemenviljelmä; Tohmajärvi; oksakulma
English keywords: Pinus sylvestris; Scots pine; height growth; heritability; branchiness; fenotyyppi; seed orchard; angle of branching
Abstract | View details | Full text in PDF | Author Info

The study material included 600 Scots pine (Pinus sylvestris L.) grafts from the Tohmajärvi seed orchard in Eastern Finland. Their broad sense heritability for the height growth was 0.92, for the number of branches 0.87 and for the angle of branching 0.84. Grafts from Central Finland had cones more often than the southern ones, the frequencies being 26.3% and 11.2%. It seems that dominance plays a significant role in the genetical variation of this seed orchard and that height growth is probably more rewarding breeding characteristic than quality, the difference being small, however.

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  • Rautiainen, E-mail: pr@mm.unknown (email)
article id 4854, category Article
G. M. Kozubov. (1971). Elektronimikroskooppisia tutkimuksia männyn ja kuusen kukka-aiheiden kehityksestä. Silva Fennica vol. 5 no. 4 article id 4854. https://doi.org/10.14214/sf.a14656
English title: Electron microscopic studies in the development of strobile primordia of Scots pine and Norway spruce.
Original keywords: kuusi; mänty; elektronimikroskopia; kasvianatomia; kasvifysiologia; kukka
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; electron microscopy; plant anatomy; plant physiology; flower; strobile primordia
Abstract | View details | Full text in PDF | Author Info

This article is an abstract from a lecture given in Helsinki on 2.12.1970. Physiological differences in different parts of developing primordia of micro- and macrostrobiles are manifested in the ultrastructure of the cell tissues. In electron microscopy, the study off metabolic activities can be combined with the anatomical examination of the flower primordia.

The generative cells of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) develop under the strong metabolic activity of surrounding layers of cells. Simultaneously the activity and development of the organelles in generative cells becomes hindered, and these inhibitions will exist until the fertilization. It can be concluded that the higher the gradient of sexualization of the cells in different parts of flower primordia, the weaker the metabolic activity in these cells.

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  • Kozubov, E-mail: gk@mm.unknown (email)
article id 4853, category Article
Olavi Luukkanen, Pentti K. Räsänen, Paavo Yli-Vakkuri. (1971). Neulasten väri myöhemmän kasvun ja lannoitusvaikutuksen ilmaisijana. Silva Fennica vol. 5 no. 4 article id 4853. https://doi.org/10.14214/sf.a14655
English title: The use of needle colour in predicting growth and response to fertilization.
Original keywords: kuusi; mänty; kasvu; taimet; lannoitus; neulaset
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; planting; growth; seedlings; needle clour
Abstract | View details | Full text in PDF | Author Info

About 4,000 seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) were planted in 1965 both on a clear-cut and sheltered area in Central Finland. In the autumn of 1966 needle colour was determined by using Muncell Color Charts which allowed a quantitative measurement of three colour dimensions (hue, value, and chroma). Terminal shoot growth was recorded for two years after colour measurements. In both species, fertilization (NPK in the spring of the year of colour measurement) as well as other site factors caused differences in all three dimensions of needle colour. A regression of shoot growth on needle colour was found in both species. In most cases colour value (darkness) and, in spruce, also chroma, predicted the subsequent growth almost as well as did these two-colour variables together.

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  • Luukkanen, E-mail: ol@mm.unknown (email)
  • Räsänen, E-mail: pr@mm.unknown
  • Yli-Vakkuri, E-mail: py@mm.unknown
article id 4849, category Article
Pentti K. Räsänen, Tapani Hänninen. (1971). Eräiden talvivarastointimenetelmien vaikutuksesta männyn taimiin. Silva Fennica vol. 5 no. 3 article id 4849. https://doi.org/10.14214/sf.a14651
English title: The effect of some over-winter storage methods on different Scots pine nursery stock.
Original keywords: mänty; taimet; varastointi; talvivarastointi; kuolleisuus; kylmävarastointi
English keywords: Pinus sylvestris; Scots pine; planting; mortality; seedlings; cold storage; winter storage
Abstract | View details | Full text in PDF | Author Info

Seedlings of three different Scots pine (Pinus sylvestris L.) nursery stock, 1+0 ,1+1, and 2+0, were kept over the winter, after they had been packed in polythene bags, in three different ways: 1) In a refrigerated storage room, 2) in a wooden crate in the ground, 3) submerged in a lake. The seedling to which they were to be compared with were left over the winter in a nursery bed. The 1,800 seedlings were planted out in the spring 1966 in 15 random blocks. Their development was scrutinized during the three subsequent falls.

The seedlings which had been stored in the lake all died. The seedlings which had been stored along the 1st and 2nd method, managed almost as well as the ones which had been kept over the winter in the nursery bed, except for those of 1+0 stock.

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  • Räsänen, E-mail: pr@mm.unknown (email)
  • Hänninen, E-mail: th@mm.unknown
article id 4847, category Article
Pentti K. Räsänen, Matti Hiltunen. (1971). Männyn erilaisten taimierien istutuskelpoisuudesta. Silva Fennica vol. 5 no. 3 article id 4847. https://doi.org/10.14214/sf.a14649
English title: The effect of differences in Scots pine nursery stock on the field survival and growth.
Original keywords: mänty; metsänviljely; istutus; kasvu; taimet; varastointi; kastelu; kuolelisuus
English keywords: Pinus sylvestris; Scots pine; planting; growth; mortality; storage; seedlings; watering
Abstract | View details | Full text in PDF | Author Info

Scots pine (Pinus sylvestris L.) seedlings were stored for five days in an ordinary wood shed. One half of the seedlings were planted out directly, and another half after soaking the roots of the seedlings for 3–6 hours in water to compensate the possible water deficit developed. According to the results of the experiment, the effect of watering was extremely small. The difference observed, which was in favour of the trees that had been watered during storage, was discernible only in the needle length and in the number of lateral buds; in mortality or in the growth of the seedlings no difference could be observed.

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  • Räsänen, E-mail: pr@mm.unknown (email)
  • Hiltunen, E-mail: mh@mm.unknown
article id 4842, category Article
Matti Leikola. (1971). Metsikkösadannan määrä eräässä hoidetussa männikössä. Silva Fennica vol. 5 no. 2 article id 4842. https://doi.org/10.14214/sf.a14644
English title: Throughfall in a managed Scots pine stand in Southern Finland.
Original keywords: Etelä-Suomi; mänty; sadanta; metsikkösadanta; sademäärä
English keywords: Pinus sylvestris; Scots pine; precipitation; throughfall; rainfall
Abstract | View details | Full text in PDF | Author Info

The purpose of the study was to measure the throughfall in a managed Scots pine (Pinus sylvestris L.) stand in Southern Finland (61°47’, 24°18’). Totally 20 summer rain gauges (collecting area 100 cm2) were placed randomly in form of a lattice of 100 squares, each 2x2 m. Six rain throughs, 15 cm x 150 cm, were placed in the experimental stand. Auxiliary precipitation measurement was done in an opening, by using four summer rain gauges, two rain throughs and one recording rain gauge. The throughfall was followed in May–September 1967.

In comparison with summer rain gauges, the rain throughs gave too low values when the precipitation was below 3 mm/rain shower. Accordingly, only the results of rain gauges were used. The rate of throughfall was determined by the amount of precipitation and the rate of heaviness of the rain shower. When trying to describe the relative amount of throughfall by using various characteristics of the stand, the equitation proposed by Seppänen (1964) proved the best. When the rate of throughfall was depicted with the distance between the summer gauge and the nearest tree, there was negative correlation between these. The correlation was negative under heavy rains, but positive in small rains.

Various factors of uncertainty are discussed. During long periods the areas under Scots pine canopies reach more rain water than those between the canopies, which may be important when analysing the spatial distribution of ground vegetation.

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  • Leikola, E-mail: ml@mm.unknown (email)
article id 4841, category Article
Hannu Mannerkoski. (1971). Lannoituksen vaikutus kylvösten ensi kehitykseen turvealustalla. Silva Fennica vol. 5 no. 2 article id 4841. https://doi.org/10.14214/sf.a14643
English title: Effect of fertilization on the initial development of Scots pine and Norway spruce plantations established by sowing on peat.
Original keywords: kuusi; mänty; turvemaat; lannoitus; itäminen; kuolleisuus; pituuskasvu
English keywords: Pinus sylvestris; Norway spruce; fertilization; Picea abies; germination; Scots pine; height growth; mortality; sowing
Abstract | View details | Full text in PDF | Author Info

Experiments were carried out to find out the effect of fertilizer application on germination, seedling emmergnece and initial development in conifer plantations established on peat by sowing, with a special reference to Scots pine (Pinus sylvestris L.). The experiments were carried out in 1968–70 in laboratory, in greenhouse and in the field.

In the greenhouse experiments with Y fertilizer for peat soils (14% N, 18% P2O5, 10% K2O) it was shown that germination and seedling emergence decreased markedly with increased fertilizer application. Mortality among seedlings that had emerged was the higher the larger quantities of fertilizer had been applied. The effect of fertilization was the greater, the drier the substrate. Fine ground rock phosphate (33% P2O5) promoted seedling emergence on a dry substrate but not on a wet one.

The field experiments carried out in Central Finland included dry and wet sites. Y fertilizer, Oulu Saltpeter (25% N), fine-ground rock phosphate and potassium salt (50% K2O) were used. According to the results, easily soluble fertilizers decreased seedling emergence. On wet sites the effect of Y fertilizer was weaker than on drier sites. Fine-ground rock phosphate slightly increased the number of seedlings emerging. Height growth was increased during the first three growing seasons only by those fertilizers containing phosphorus.

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  • Mannerkoski, E-mail: hm@mm.unknown (email)
article id 4838, category Article
Kustaa Seppälä. (1971). Metsityslannoituksessa käytetyn lannoitemäärän ja levitystavan merkitys istutustaimiston alkukehitykselle ojitetuilla avosoilla. Silva Fennica vol. 5 no. 2 article id 4838. https://doi.org/10.14214/sf.a14640
English title: The quantity of fertilizer and application methods used in afforestation of open bogs.
Original keywords: mänty; istutus; metsitys; taimet; turvemaat; lannoitus; ojitetut suot; avosuot; kuolleisuus; pituuskasvu
English keywords: Pinus sylvestris; fertilization; afforestation; drained peatlands; Scots pine; height growth; mortality; seedlings
Abstract | View details | Full text in PDF | Author Info

The paper describes the results obtained from an experiment of fertilization of drained treeless peatlands in connection of planting in three sites in Central Finland. Scots pine (Pinus sylvestris L.) seedlings 2+0 was used. The fertilizer (Y-fertilizer for peat soils, 14% N, 18% P2O5, 10% K2O) was applied in rates of 0, 20, 40 and 80 g/transplant. The fertilizer was strewn either around the plant within a circular patch of 20 cm in diameter, in a ring with a radius of 10 cm and in a ring with a radius of 20 cm. The seedlings were measured two and five years after planting.

The greater the quantity of fertilizer applied and the closer it was applied to the plant the higher was the mortality of transplants. Fertilization increased the mortality during the first two growing seasons after application. Later, however, the mortality decreased to a similar level irrespective the way the fertilizer was applied. In the beginning of the second growing season the fertilized plants showed considerably better height growth than the control plants. The smallest quantity of fertilizer applied produced almost full increase in growth. The pattern of application of the fertilizer had little effect on the growth.

It was concluded that a use of small amounts of fertilizer can be recommended in connection with planting and that it should not be applied very near the seedlings.

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  • Seppälä, E-mail: ks@mm.unknown (email)
article id 4834, category Article
Bo Långström. (1971). Weight loss, water content and mortality of cold stored Scots pine seedlings. Silva Fennica vol. 5 no. 1 article id 4834. https://doi.org/10.14214/sf.a14623
Keywords: Pinus sylvestris; Scots pine; mortality; seedlings; cold storage; weight loss; water content; storage conditions
Abstract | View details | Full text in PDF | Author Info

The aim of this study was to investigate how the weight loss and water content of cold stored plants depend on the storage conditions, and if there is a clear connection between these factors and the field survival of the planting stock. The experiments were carried out in a climate chamber at about +2°C and at three moisture levels (about 70, 85, and 95%) from November 1968 to May 1969. Three-year-old seedlings of Scots pine (Pinus sylvestris L.) average length 127 mm, diameter 3.5 mm and the top/root-ratio of fresh weight 1.93, were stored in open and sealed plastic bags. In addition, a transpiration retardant (Silvaplast) was used. The plastic bags (10 plants each) were weighted every 4. week. The remaining 270 seedlings were planted out and inspected after one growing season.

Although the experiment was made in a small scale, the results showed clearly that plant mortality, varying between 3 and 97%, was due to the storage conditions. The weight loss ranged between 2 and 50%, and the correlation between the weight loss and the mortality in the field was high. The water content of the seedlings was about 61%. The correlation between water content and survival was very high. Thus, the determination of weight loss or water content could be a useful method in observing the changes of water balance of the seedling stock during winter-storage. Further investigations are needed to show the tolerable rate of drying out for different sorts of plants. The Silvaplast-treatment had no visible effect either on the drying out or on the field survival.

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  • Långström, E-mail: bl@mm.unknown (email)
article id 4832, category Article
Paavo Yli-Vakkuri, Pentti K. Räsänen. (1971). Siementen peittämisen ja kylvökohdan polkaisun vaikutus männyn ruutukylvön tulokseen. Silva Fennica vol. 5 no. 1 article id 4832. https://doi.org/10.14214/sf.a14621
English title: The influence of covering and tramping the seeds into the soil on the success of spot sowing of Scots pine.
Original keywords: kylvö; mänty; metsänviljely; taimettuminen; itäminen; kylvösyvyys; siementen suojaus; ruutukylvö
English keywords: Pinus sylvestris; germination; Scots pine; sowing; artificial regeneration; covering of the seeds; stocking with seedlings
Abstract | View details | Full text in PDF | Author Info

This paper reports spot sowing experiments of Scots pine (Pinus sylvestris L.). The seeds were either covered with coarse sand, tramped in the substrate or sowed without any covering, 30 seeds in each treatment in 70 replications. The site was of Vaccinium type with sandy soil. The germination percentage was 81 and 91 on the respective years. The development of seedlings was observed for 3–4 years.

The results indicate that both tramping and covering the seeds to some extent increased the number of seedlings and improved the early development. The highest numbers of seedlings were recorded in the first growing season, after which there was 23 seedlings/100 seeds in the uncovered spots, 27 seedlings in the covered spots and 31 seedlings in the tramped spots in the experiment sowed in 1965.

Mortality of the seedlings was highest between the first and second growing season, and empty spots increased with the time. There was no difference in mortality between the sowing methods, but the number of seedlings after first growing season affected the result. Under favourable conditions four seedlings per spot seemed enough to secure the survival of minimum one seedling per spot during the three first growing seasons. In poor conditions seven seedlings was needed.

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  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
  • Räsänen, E-mail: pr@mm.unknown
article id 4831, category Article
Lauri Mikkola. (1970). Kuusilajien risteytyvyydestä. Silva Fennica vol. 4 no. 4 article id 4831. https://doi.org/10.14214/sf.a14620
English title: On the crossability of Picea species.
Original keywords: mänty; metsänjalostus; itävyys; kuuset; risteytys; risteytyskokeet; keinollinen pölytys
English keywords: Pinus sylvestris; Picea abies; tree breeding; Picea; Abies; controlled pollination; interspecific sterility; hybrids; crossbreeding
Abstract | View details | Full text in PDF | Author Info

Seed development was microscopically studied after controlled pollinations. In all the interspecific crosses incompatibility occured. In the following crosses the growth of all the pollen tubes stopped before they had penetrated through the nuclear cap: Picea abies (L.) Karst. x mariana, abies x jezoensis (and the reciprocal), abies x omorika (and the reciprocal), mariana x asperata, mariana x jezoensis and Picea abies x Pinus sylvestris L.

Some of the eggs were fertilized in the crosses Picea abies x glauca (and the reciprocal) abies x asperata, abies x koyamai, abies x obovata, mariana x omorika and jezoensis x omorika. Embryo degeneration was observed in all these crosses. All the embryos died in the crosses abies x glauca (and the reciprocal) as well as jezoensis x omorika. Adequate amounts of full seed for germination test was obtained from the crosses abies x asperata, abies x koyamai and abies x obovata. In all these crosses there were seeds which were able to germinate and the hybrids are now one growth season old.

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  • Mikkola, E-mail: lm@mm.unknown (email)
article id 4823, category Article
Christel Palmberg. (1970). Heritabiliteetin arvioiminen eräässä männyn (Pinus silvestris L.) jälkeläiskokeessa. Silva Fennica vol. 4 no. 3 article id 4823. https://doi.org/10.14214/sf.a14612
English title: Estimation of heritability in open-pollinated plus tree progenies of Pinus sylvestris L.
Original keywords: mänty; oksikkuus; metsänjalostus; pluspuut; pituuskasvu; perinnöllisyys
English keywords: Pinus sylvestris; Scots pine; height growth; tree breeding; heritability; branchiness; plus trees
Abstract | View details | Full text in PDF | Author Info

Field experiments of Scots pine (Pinus sylvestris L.) was established by planting seedlings grown from seeds collected from open-pollinated plus trees throughout the country. The 36 progenies represented were planted in 4 blocks as 2+2 transplants in 1960. The main characteristics of the seedlings were measured in 1966 and 1968. Considerable damage had been caused to the stands by moose (Alces alces) and Melampsora pinitorqua Rostr., consequently, therefore, only normally developed seedlings were measured.

Highly significant differences between progenies were found in the number of branches in 1968 and in the ratio of height of tree to the length of the longest branch. In 1968, the differences in height between progenies were not significant, but there were significant differences between blocks both in tree height and length of terminal shoot. Obviously, the edaphic heterogeneity of the site has influenced mainly the juvenile growth of the plants, because in the length of the terminal shoot there could be seen also significant differences between the progenies. There were no significant differences between the progenies in the length of the longest branch, in the angles of the thickest branches, in stem taper and in the diameter of the thickest branch.

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  • Palmberg, E-mail: cp@mm.unknown (email)
article id 4817, category Article
Leo Heikurainen, Jukka Ouni. (1970). Turvemaiden taimistojen pituuskasvusta. Silva Fennica vol. 4 no. 2 article id 4817. https://doi.org/10.14214/sf.a14606
English title: Height growth of seedling stands growing on peatland.
Original keywords: kuusi; mänty; turvemaat; lannoitus; ojitetut suot; taimikot; pituuskasvu; ylispuusto
English keywords: Pinus sylvestris; Norway spruce; fertilization; Picea abies; drained peatlands; Scots pine; height growth; peatlands; seedling stands; hold-overs
Abstract | View details | Full text in PDF | Author Info

This paper presents the results of a contest performed on behalf of the Finnish bank Kansallis-Osake-Pankki and the Central Forestry Board Tapio on growing trees on peatlands. Over 5,000 sample plots were established on drained peatlands in various parts of Finland. The aim was to achieve a best possible growth of seedling stands on peatland. The factors influencing the growth of 85 best Scots pine (Pinus sylvestris L.) and 60 best Norway spruce (Picea abies (L.) H.Karst.) sample plots were studied.

The height growth of the seedling stands decreased towards the north. Fertilization seemed not to decrease the regional differences; rather on the contrary. On the other hand, fertilization increased height growth, but evidently so that the increase obtained was greater in the southern than in the northern parts of the country. Light fertilization (50 kg/ha of K2O and 60 kg/ha of O2P5) caused a clear increase in height growth while heavy fertilization (100 g/ha of K2O and 120 kg/ha of O2P5), had same effect but to much greater extent than the former. Spruce seedling stands in particular benefitted of the heavy fertilization.

Fertilization did not eliminate the original differences in the quality of the sites in question, but these could still be seen in the height growth after fertilization. The effect of drain spacing on the height growth was not very clear. In dense seedling stands (800 seedlings/ha) the height growth of the dominant seedlings was greater than that obtained in stands of lower density. Hold-overs caused a decrease in the growth of the seedling stands.

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  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Ouni, E-mail: jo@mm.unknown
article id 4816, category Article
P. M. A. Tigerstedt, Eero Malmivaara. (1970). Metsänjalostuksen mahdollisuudet I.Pluspuiden valintaero ja siemenviljelysten valintahyöty. Silva Fennica vol. 4 no. 2 article id 4816. https://doi.org/10.14214/sf.a14605
English title: The possibilities in forest tree breeding. I Selection differential of plus trees and genetic gain in seed orchards in Finland.
Original keywords: mänty; metsänjalostus; siemenviljelmät; pluspuut; valintahyöty; periytyvyys; vieraspölytys
English keywords: Pinus sylvestris; Scots pine; tree breeding; seed orchards; genetic gain; heredity; selection differential; foreign pollen sources
Abstract | View details | Full text in PDF | Author Info

An attempt was made to estimate critically the genetic gain in clonal seed orchards of Scots pine (Pinus sylvestris L.) in Finland. The selection differential of Scots pine and Norway spruce (Picea abies (L.) H. Karst.) is calculated on the basis of filed information on selected plus trees which has been kept by the genetic register at the Finnish Forest Research Institute. The differentials were computed as realized differences in height between plus-trees and normal stand characteristics on respectively site class and as a function of age.

The genetic gain in height growth of Pinus sylvestris was computed on the basis of information on selection differential and heritability. This genetic gain is between 2.6–4.4% provided there is no pollen contamination from unknown sources outside the seed orchard. The genetic gain of volume growth in Scots pine is about 7–15%, provided there is no pollen contamination in the seed orchard. However, according to investigations, there is invariably some pollen contamination in this kind of seed orchards. The contamination decreases to about 30–50% as the orchard matures and starts to produce endemic pollen. If the pollination would be entirely due to foreign pollen sources, the mathematically calculated genetic gain would be 3.5–7.5%.

The PDF includes a summary in English.

  • Tigerstedt, E-mail: pt@mm.unknown (email)
  • Malmivaara, E-mail: em@mm.unknown
article id 4813, category Article
Bo Långström. (1970). Pakkaustapojen vaikutuksesta talvivarastoitujen männyn taimien istutukseen. Silva Fennica vol. 4 no. 1 article id 4813. https://doi.org/10.14214/sf.a14602
English title: The effect of packing methods on the field survival and growth of winter-stored plants of Scots pine.
Original keywords: mänty; metsänviljely; istutus; kasvu; taimet; kylmävarasto; talvivarastointi; kuolleisuus; tukkimiehentäi; torjunta-aine
English keywords: Pinus sylvestris; nursery; Scots pine; planting; seedlings; cold storage; winter storage; Hylobious abietis; large pine weevil; insecticide; field survival; packing methods
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to investigate the effect of four packing methods on the field survival and growth of seedlings and transplants of Scots pine (Pinus sylvestris L.) stored over the winter in a cold-storage cellar. The following sorts of plants were used: one-year-old seedlings (1+0) grown in a plastic greenhouse, two-year-old (2+0) open grown seedlings and three-year-old open grown transplants. These plants were stored in open wooden boxes, in sealed plastic bags, in boxes with wet peat on the bottom and in plastic-laminated paper bags.

The control plants were of the same types and were kept in a nursery over the winter. The storage was carried out in a mantle-chilled cold-storage from October 1966 to May 1967. The temperature in the cold-storage was kept around -2 °C and the relative humidity of the air over 90%. The water content of a randomly selected sample plants showed no increase in water deficit after the storing. Part of the seedlings were transplanted in the nursery and the rest were planted in a clear-cut area. A number of the latter plants were treated with an insecticide (1% Intaktol, which contains DDT, Lindane and dieldrin) before planting. All the experiments were examined after one growing season and the planting experiments the next fall.

The transplants (2+1) in the nursery, and in the forest had survived and grown better than the seedlings. In the nursery the 1+0 seedlings survived and grew better than the 2+0 seedlings. There was no difference in mortality between the seedlings. After the first growing season occasional significant differences between the packing methods were observed, but they disappeared during the second growing season. Thus, all packing methods proved to be as successful as the control method without winter storage.

Transplants were more often attacked by the large pine weevil (Hylobius abietis L.) than the smaller seedlings. The damage, however, was considerably greater on the seedlings because of their lower resistance. No significant differences in the Hylobius-attack between the packing methods could be observed. The Intaktol-treated plants were as often attacked as the untreated ones, but the damage was slighter on the treated ones.

The PDF includes a summary in English.

  • Långström, E-mail: bl@mm.unknown (email)
article id 4812, category Article
Pentti K. Räsänen, Aarno Koukkula, Paavo Yli-Vakkuri. (1970). Pakkauksen, varastoimisen ja valeistutuksen vaikutus männyn taimien istutuskelpoisuuteen. Silva Fennica vol. 4 no. 1 article id 4812. https://doi.org/10.14214/sf.a14601
English title: The effect of packing, storing and heeling-in on the field survival and growth of Scots pine seedlings.
Original keywords: mänty; metsänviljely; istutus; metsäpuun taimet; taimet; varastointi; kuolleisuus; kastelu; tukkimiehentäi
English keywords: Pinus sylvestris; Scots pine; planting; mortality; storage; Hylobius abietis; seedlings; large pine weevil; insecticide; field survival
Abstract | View details | Full text in PDF | Author Info

The aim of the present study was to establish, by means of planting experiments, the influence of different packing, heeling-in and watering as well as the length of the storage period on the development of Scots pine (Pinus sylvestris L.) seedlings, in all 2,090 seedlings, that had been lifted from the nursery bed in spring. The plants were packed in bundles and into plastic sacks in 1965 (6 storage methods) and in 1966 (3 storage methods). Control seedlings were planted without storing at the time when storage of the test material begun. The plantations were followed 3–4 years.

Storage for two weeks in the different ways and planting without storage gave similar results when seedling survival was compared. Storage in plastic sack proved to be as good as storage in bundles in a cellar, and healing-in in moist soil or in a drain were both usable methods. Watering the seedlings did not improve the results, which indicates that the storage caused no serious lack of water.

After four growing seasons an average of 19,6% of the seedlings of the 1965 experiment died, the bulk of them by the end of the first growing season. Despite control treatment, Hylobious abietis caused serious damages. In the plantations of the year 1966 mortality of the seedlings was under 5% by the end of third growing season. During the first two growing seasons after planting differences in growth of the seedlings stored in different ways could be observed in the plantations of the year 1965, but the differences levelled out later. In the plantations established in 1966 no differences in growth occurred.

The PDF includes a summary in English.

  • Räsänen, E-mail: pr@mm.unknown (email)
  • Koukkula, E-mail: ak@mm.unknown
  • Yli-Vakkuri, E-mail: py@mm.unknown
article id 4808, category Article
Erkki Lähde, Antti Oksanen. (1969). Morfologiset, gravimetriset ja fotometriset tunnukset männyn taimien juuristojen kuvaajina. Silva Fennica vol. 3 no. 4 article id 4808. https://doi.org/10.14214/sf.a14596
English title: Morphological, gravimetric, and photometric characteristics in describing of the root systems of pine transplants.
Original keywords: mänty; Pinus sylvestris; juuristo; taimet; mittausmenetelmät; juurten pinta-ala; morfologia
English keywords: Scots pine; seedlings; root system; surface area of the root system; morphology
Abstract | View details | Full text in PDF | Author Info

This project studied the value of various shoot and root-system characteristics as indicators of plantability of transplants. Correlation and regression analysis was used to compare these characteristics. The study material consisted of two-year Scots pine (Pinus sylvestris L.) transplants that had grown in a plastic greenhouse for the first year and then been transplanted in the open. The seedlings had been transplanted in the field without treatment or with the roots cut to a length of 8 cm. A part was transplanted without treatment into plastic pails. A gravimetric and photometric method was used to obtain a description of the surface area of the root systems.

The results show that the photometric value gives a good picture of the surface area of the root system. The greatest advantage offered by the method is the simplicity and rapidity of measurement. The gravimetric, and especially the titrimetric, measurement takes much more time per plant. Photometric measurement affects plantability little, and measured and planted transplants can be followed up in the field. In gravimetric measurements, it was found that fresh and dry weight of the plants were closely correlated.

Mycorrhizal frequency in the root systems gave a good picture of the surface area of the root system. The number of living roots-tips was also rather closely correlated with the surface area of the root system. The other morphological characteristics failed to serve as a satisfactory index for the surface area of root systems. The one closest correlated was the annual leader growth. The second best was stem diameter; the height of the plant, on the contrary, was rather poorly correlated with the other characteristics.

The PDF includes a summary in English.

  • Lähde, E-mail: el@mm.unknown (email)
  • Oksanen, E-mail: ao@mm.unknown
article id 4803, category Article
Kari Löyttyniemi. (1969). Männyn ja kuusen siemenien esikäsittelyn vaikutuksesta itämiseen ja taimien alkukehitykseen kasvihuoneoloissa. Silva Fennica vol. 3 no. 3 article id 4803. https://doi.org/10.14214/sf.a14591
English title: The effect of treatment of Scots pine and Norway spruce seeds on their germination and the early development of the seedlings.
Original keywords: kuusi; mänty; taimettuminen; itäminen; esikäsittely; siemenet; taimikuolleisuus
English keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; Scots pine; seedlings; seeds; treatment of seeds; mortality of seedlings
Abstract | View details | Full text in PDF | Author Info

The aim of this study was to establish the need of treatment of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seeds to be sown in greenhouse. 3 x 100 seeds of each treatment (soaking in water, treatment with Pb3O4, treatment with tiram-containing coating substance) were sown in a glasshouse on a fertilized garden peat, and covered with peat layer of 6 mm thickness. The development of seedlings was followed for 100 days before the final measurement.

Soaking the seeds with water made germination somewhat faster. In spruce the germination percentage increased, but the opposite was observed in pine. No difference could be observed between the results from soaking with acid water from peat soil and lake water. Drying the soaked seeds for a week before sowing had no harmful influence on the germination or the early development of the seedlings. Treatment with Pb3O4 did not affect the germination speed or the seedling percentage of pine or spruce, but increased the germination percentage of spruce. Coating decreased germination and seedling percentages in pine. However, the differences between the treatments were so small that their practical significance is negligible.

Germination of both the species initiated on an average in 8 days, and 16 days after sowing 80% of the seeds had germinated. Seedling mortality was about 10% of the total number of seedlings, the most common reason being damping-off.

The PDF includes a summary in English.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
article id 4786, category Article
Matti Leikola. (1969). Havaintoja männyn paksuuskasvun loppumisesta ja puiden keloutumisesta Inarin Lapissa. Silva Fennica vol. 3 no. 1 article id 4786. https://doi.org/10.14214/sf.a14572
English title: Termination of diameter growth of Scots pine in old age in northernmost Finnish Lapland.
Original keywords: mänty; Lappi; läpimitan kasvu; kelo; kasvun päättyminen
English keywords: Pinus sylvestris; Scots pine; Lapland; diameter growth; termination of growth
Abstract | View details | Full text in PDF | Author Info

The purpose of the present study is to throw light on the termination of diameter growth of Scots pine (Pinus sylvestris L.) in old age in northernmost Finnish Lapland. The material consists of thirty over-mature, dying or already dead standing trees grown in natural state. In 1907 the stand was marked for cutting, but the harvest was never carried through. Now the old labels served as a means for cross-dating the year of the final termination of growth.
It was found that as pine becomes senile its annual ring formation becomes incomplete. At first diameter growth stops in the middle part of the stem, then at the butt end, and at last on the canopy level. No correlation between the mean temperature of July and the dying of the tree was found. The average age for dying for the pine in the stand was 420–450 years. After the tree has died it takes about 35–40 years before it has become a silvery, branchless dead bole.

The PDF includes a summary in English.

  • Leikola, E-mail: ml@mm.unknown (email)
article id 4778, category Article
Kari Löyttyniemi. (1968). Teeri (Lyrurus tetrix L.) männyn taimien tuholaisena taimitarhassa. Silva Fennica vol. 2 no. 4 article id 4778. https://doi.org/10.14214/sf.a14563
English title: Feeding of terminal shoots of Scots pine seedlings by the black grouse (Lyrurus tetrix) in nursery.
Original keywords: mänty; taimitarha; taimituhot; versot; teeri
English keywords: Pinus sylvestris; nursery; Scots pine; forest nursery; seedling damages; feeding behaviour; black grouse; Lyrurus tetrix; terminal buds
Abstract | View details | Full text in PDF | Author Info

In early spring 1968 it was noticed that the black grouses (Lyrurus tetris L.) was eating terminal shoots of Scots pine (Pinus sylvestris L.) seedlings in a tree nursery in Luumäki, Southern Finland. The terminal shoots were picked 1–4 cm from the top of the seedlings. In total some thousands of two-year-old seedlings were damaged. The depth of the snow was 10–15 cm deep and only the tops of the seedlings could be seen above the surface of the snow.

The PDF includes a summary in English.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)
article id 4771, category Article
J. G. Gordon, G. E. Gatherum. (1968). Photosynthesis and growth of selected Scots pine populations. Silva Fennica vol. 2 no. 3 article id 4771. https://doi.org/10.14214/sf.a14556
Keywords: Pinus sylvestris; photosynthesis; Scots pine; height growth; provenance; growth; photoperiod
Abstract | View details | Full text in PDF | Author Info

Eight Scots pine (Pinus sylvestris L.) seed sources, ranging from 42° to 66° north latitude, were grown under a constant, 16-hour photoperiod in a greenhouse for approximately 6 months. Rates of photosynthesis, as measured by an IRGA, and growth, as measured by increase in height and fresh and dry weight, differed among seed sources at the end of the six-month growing period. Photosynthetic capacity and growth were strongly related to latitude of seed source, and were greatest in the seed sources coming from a parent environment in which maximum photoperiods are about 16 hours.

Photosynthetic efficiency (rate of photosynthesis per gram needle weight) was also strongly related to latitude of seed source, but was lowest in the seedlings which exhibited the greatest growth and photosynthetic capacity. This may have been due to (1) more mutual shading of needles on the larger seedlings and (2) a lesser proportion of juvenile needles on the larger seedlings or (3) biochemical differences in the use of photosynthate in the needles. Seed source and light intensity had an interacting effect on rates of photosynthesis only in seedlings of the two northernmost seed sources.

The PDF includes a summary in Finnish.

  • Gordon, E-mail: jg@mm.unknown (email)
  • Gatherum, E-mail: gg@mm.unknown
article id 4764, category Article
Juhani Päivänen. (1968). Istutusajankohdan vaikutus männyn istutuksen onnistumiseen ojitetuilla avosoilla. Silva Fennica vol. 2 no. 2 article id 4764. https://doi.org/10.14214/sf.a14549
English title: The effect of the date of planting on the survival of Scots pine on drained open peatlands in Finland.
Original keywords: mänty; istutus; metsitys; ojitusalueet; turvekankaat; istutusaika; avosuot; syysistutus
English keywords: Pinus sylvestris; afforestation; drained peatlands; Scots pine; planting; time of planting; autumn planting; open peatlands
Abstract | View details | Full text in PDF | Author Info

Due to mechanization of draining of peatlands, also open peatlands have been included in the draining projects due to technical reasons. Some research has been published on afforestation of open drained peatlands, but there is yet no experiments that reaches the entire development of the stands. The purpose of this paper is to discuss the possibility of extending the planting season of Scots pine (Pinus sylvestris L.) over the entire growing season in drained peatlands, where the water condition of the site is probably not the factor limiting forest development. An open low-sedge swamps in Southern Finland were planted in early summer and two weeks in midsummer in 1967.

In the light of the results, planting Scots pine would seem possible in drained peatlands throughout the growing season. However, plants may suffer considerably from lifting for the plantation in August. The success of planting at the turn of September and October is also uncertain. The nursery must be situated close to the areas to be planted, since the transportation and handling of plants during the growing season must be carried out with extreme care. The seasonality of planting work could be decreased by extending the planting season. In the future, several transplant storing methods should be tried out in connection with similar planting-time experiments.

The PDF includes a summary in English.

  • Päivänen, E-mail: jp@mm.unknown (email)
article id 4756, category Article
Bo Eklund. (1967). Annual variation of increment in Scots pine and Norway spruce in Sweden. Silva Fennica vol. 1 no. 4 article id 4756. https://doi.org/10.14214/sf.a14540
Original keywords: kuusi; mänty; läpimitan kasvu; vuosilustot; vuosikasvu; kasvun vaihtelu; kasvuindeksi
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; diameter growth; annual rings; annual growth; annual ring index series
Abstract | View details | Full text in PDF | Author Info

This lecture discusses the problem of the annual variation in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.), and its significance. A newly constructed instrument for field measurements of diameter growth is described, also the latest of the Royal College of Forestry’s series of machines for annual ring measurement. The method of constructing an annual ring index is also mentioned.

Examination of material from undisturbed stands in Northern Sweden has shown that the annual ring index series for pine are characterised by a relatively marked autocorrelation, which increases with latitude, implying that the annual ring index for a given calendar year is positively correlated with that for the year immediately preceding it. However, this seems not to be so in spruce, in which the annual ring index series is marked by the effect of the changes in cone production from the year to year. The annual ring index for spruce may be expressed in the form of climatic functions, according to which the index can be approximately calculated or known values of the meteorological variables contained in the function, in association with numerical expressions for the cone production. By means of a number of examples illustrating annual ring series from thinned stands. It is shown finally how the response to thinning can be presented in a more essential form from the variation in the annual rings, and how climatically corrected increment can be determined.

The PDF includes a summary in English.

  • Eklund, E-mail: be@mm.unknown (email)
article id 4754, category Article
Matti Leikola. (1967). Havaintoja erään hoidetun männikön tuulisuhteista. Silva Fennica vol. 1 no. 3 article id 4754. https://doi.org/10.14214/sf.a14538
English title: Observations on wind conditions in a managed Scots pine stand.
Original keywords: mänty; tuulisuus; metsikkö; pienilmasto; lämpötila; tuuli
English keywords: Pinus sylvestris; wind; Scots pine; temperature; wind velocity; wind conditions; stand climate; microclimate
Abstract | View details | Full text in PDF | Author Info

An explorative study on wind conditions in a well-managed Scots pine (Pinus sylvestris L.) stand was made in Southern Finland. The wind velocity was recorded continually with two cup anomometers from April to August, 1964. The two levels used were 2 m and 9 m. The wind velocity was lower at 2 m than within the canopy at 9 m. The dependence on the absolute wind velocity at 9 metres was logarithmic. The wind velocity did affect the difference between daily minimum temperatures at the two levels; the difference in the maximum temperatures was affected only in May and August.

The PDF includes a summary in English.

  • Leikola, E-mail: ml@mm.unknown (email)
article id 4745, category Article
Ilmari Schalin. (1967). Microfungi in the humus layer of pine, spruce and birch stands in southern Finland. Silva Fennica vol. 1 no. 2 article id 4745. https://doi.org/10.14214/sf.a14455
Keywords: Pinus sylvestris; Betula; Picea abies; forest soil; humus; fungi; microfungi; yeast
Abstract | View details | Full text in PDF | Author Info

This study elucidates the composition of the microfungal populations of the humus layer of tree forest types – Vaccinium type with Scots pine (Pinus sylvestris L.), Myrtillus type with Norway spruce (Picea abies (L.) H. Karst.) and Oxalis-Myrtillus type with birch (Betula sp.). The results indicate that the microfungi encountered in these sites bear close resemblances. The number of species increased but little towards the more fertile sites from VT to OMT. The main difference was limited to the quantitative relationships between the species.

The microfungal density in the humus layer was greatest in VT, and only slightly less in MT and OMT, in this order. In all the sampling areas, occurrence of the microfungi reached a maximum in the middle of summer, at a time when the maximum temperatures were registered in the humus. The quantitative abundance during the early autumn bears a relation to the yield of litter.

The microfungi most commonly encountered in all sampling areas were those of rapid growth, Mucor, Morierella and Penicillium species, along with Trichoderma, a little slower in growth, and actively decomposing cellulose. Mucor fungi, favouring moisture, were most abundant in the early summer and in the autumn. The Mortierella and Penicillium species, which survive dryness, were most abundant in the middle of the summer. The former is twice as common in MT and OMT than in VT, and the latter twice as common in VT as in OMT.

Scopulariopsis and Verticillium species were found regularly in MT and OMT. One Acremonium species was found almost exclusively in VT, and some Aspergillus and Mycogene in OMT alone. Sterilia mycelia was relatively abundant in MT and OMT in particular. Different kinds of yeast fungi were encountered generally in MT and OMT.

The PDF includes a summary in Finnish.

  • Schalin, E-mail: is@mm.unknown (email)
article id 4732, category Article
Juhani Päivänen. (1966). Sateen jakaantuminen erilaisissa metsiköissä. Silva Fennica no. 119 article id 4732. https://doi.org/10.14214/sf.a14290
English title: Distribution of rainfall in different types of forest stands.
Original keywords: kuusi; mänty; koivu; puulajit; sadanta; metsikkösadanta; runkovalunta
English keywords: Pinus sylvestris; Norway spruce; birch; Betula; Picea abies; Scots pine; tree species; precipitation; throughfall; stem flow
Abstract | View details | Full text in PDF | Author Info

Stand precipitation and stemflow studies became necessary in connection with hydrologic studies, for instance, to explain the deviations resulting from rains in the ratios between the water content of peat and the groundwater level, throughfall during rains of variable heaviness, and effect of stand treatment on soil moisture level. In this project the distribution of rainfall in stands differing in species composition and density was studied in Central Finland in 1963–1965 in fifteen stand precipitation sample plots. In addition, rain gauges were situated under individual Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) and birch (Betula sp.) trees.

The average precipitation in the open was 4.8 mm, the corresponding precipitation in the stand was 77% for birch, 71% for pine and 62% for spruce. Measurements of stemflow from individual sample trees showed that less than ¼ mm (about 1.5%) during a 15 mm rain in a pine stand. In the spruce stands stemflow is negligible. A part of the sample plots was in drained peatlands with a dense vegetation of small shrubs. The shrub layer retention was about 10% even during heavy rain. In a small forest clearing, the bordering effect of the forest was seen up to the distance of 5 metres from the edge of the forest. During the period of study, on an average 3% more precipitation was recorded in the clearing than in the open, the difference being probably due to the stronger wind effect in the open.

The PDF includes a summary in English.

  • Päivänen, E-mail: jp@mm.unknown (email)
article id 4731, category Article
Leo Heikurainen, Juhani Päivänen, Kustaa Seppälä. (1966). Koetuloksia männyn kylvöstä ja istutuksesta ojitetuilla soilla. Silva Fennica no. 119 article id 4731. https://doi.org/10.14214/sf.a14289
English title: Scots pine seeding and planting on drained peat soils.
Original keywords: kylvö; mänty; istutus; uudistaminen; lannoitus; turvekankaat; ojitetut suot
English keywords: Pinus sylvestris; fertilization; regeneration; Scots pine; planting; sowing; artificial regeneration; seeding
Abstract | View details | Full text in PDF | Author Info

This paper describes the preliminary results of Scots pine (Pinus sylvestris L.) seeding and planting trials on drained peat soils.

The results showed that a perpared peat surface was a better surface for seeding than the unprepared one. Planting of 2+1-year seedlings succeeded better than planting 1-year seedlings. Planting on the turf gave better survival than planting on the unprepared soil surface. The whole growing season was suitable time for planting Scots pine seedlings except May when the peat soil under the surface was still frozen.

Using fertilizers in connection with planting was surveyed in two ways. Mortality of seedlings increased when they were top-dressed with NPK fertilizer. Using a so-called spot fertilizing with several combinations of fertilizers resulted in K and N tending to increase the mortality of seedlings, but P decreasing mortality.

The PDF includes a summary in English.

  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Päivänen, E-mail: jp@mm.unknown
  • Seppälä, E-mail: ks@mm.unknown
article id 4727, category Article
Erkki Pulliainen, Kalervo Salonen. (1965). Orava männyn siemen- ja silmutuholaisena. Silva Fennica no. 117 article id 4727. https://doi.org/10.14214/sf.a14285
English title: Damage caused by squirrel (Sciurus vulgaris) to pine-buds.
Original keywords: mänty; taimituhot; kasvutappiot; orava; silmut
English keywords: Pinus sylvestris; Scots pine; seedling damages; squirrels; Sciurus vulgaris; buds
Abstract | View details | Full text in PDF | Author Info

When the seed harvest of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) are low, pine and spruce buds are among the secondary food items of squirrel (Sciurus vulgaris L.) in Finland. In this study, conducted in Nokia in Southern Finland in 1962-1963, eating of pine buds by squirrel is described. The eaten buds in 15-years old Scots pine seedlings were recorded in two seedling stands.

According to the results, the squirrels selected the largest buds of the best seedlings in the studied stands. In over 50% of the cases the squirrels chose only the buds of the leading shoot, especially the terminal bud. In half of the trees, a side bud of the leading shoot continued the growth, which causes form defects in the trees. In 35% of the damaged trees, a lateral branch continued the growth. Well-growing seedling stands may be especially susceptible for damages caused by, for instance, squirrels.

The PDF includes a summary in Finnish.

  • Pulliainen, E-mail: ep@mm.unknown (email)
  • Salonen, E-mail: ks@mm.unknown
article id 4725, category Article
Carl Olof Tamm. (1965). Some experiences from forest fertilization trials in Sweden. Silva Fennica no. 117 article id 4725. https://doi.org/10.14214/sf.a14283
Original keywords: Ruotsi; kasvu; lannoitus; turvekankaat
English keywords: Pinus sylvestris; Norway spruce; fertilization; Picea abies; drained peatlands; Scots pine; Sweden; increment
Abstract | View details | Full text in PDF | Author Info

The many unsolved questions concerning fertilization makes it difficult to forecast accurately its biological and economic consequences. Some of the problems are discussed in this paper. The most common types of forests in Sweden, Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands on well-drained mineral soil, respond strongly to nitrogenous fertilizers, but the effect of phosphate, potash or lime is small or nil, at least within 5–10 years after application. The response of nitrogen lasts 4–5 years in pine and somewhat more in spruce.

Drained peatlands usually respond to mineral fertilization, but the improvement brought about by a PK application depends, inter alia, on the nitrogen content of the peat. Peatlands with a peat low in nitrogen need NPK fertilization. For deep peatlands, a moderate or high nitrogen content, a single PK application improves growth conditions for a very long time. Experience of fertilizing shallow peatlands and poorly-drained mineral soil is very limited, but it seems easy to get a growth response either with nitrogen alone or with NPK.

The results of fertilization at the time of planting have not, as a rule, been very good in Sweden. An exception is the afforestation of abandoned fields on drained deep peat, where PK fertilizer around the plant seems to be essential for both survival and growth.

  • Tamm, E-mail: ct@mm.unknown (email)
article id 4703, category Article
E. A. Jamalainen. (1961). Havupuiden taimistojen talvituhosienivauriot ja niiden kemiallinen torjunta. Silva Fennica no. 108 article id 4703. https://doi.org/10.14214/sf.a9138
English title: Damage by low-temperature parasitic fungi on coniferous nurseries and its chemical control.
Original keywords: kuusi; mänty; taimet; taimituhot; torjunta-aineet; havupuut; taimitarhat; sienitaudit; talvituhosienet
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; fungicides; seedlings; coniferous seedlings; seedling damages; pathogens; nurseries
Abstract | View details | Full text in PDF | Author Info

Since 1954 studies have been carried out by the Department of Plant Pathology of Agricultural Research Centre on occurrence of low-temperature parasitic fungi in nurseries in Finland. This paper reports analysis of the damage caused by the fungus to Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seedlings.

In Southern and southwestern Finland, scarcely any damage caused by low-temperature parasitic fungi to coniferous seedlings was found. On the other hand, in Central, Eastern and Northern Finland, considerable injuries were present in the seedlings. The extent of damage varies between different localities and in a same location from year to year. The extent of damage is mostly dependent on snow cover which is heaviest in Central and Northern Finland. Damages are largest in wooded areas and in places where snow accumulates abundantly and remains until late in the spring.

The principal cause of winter damage to spruce seedlings is Hepotricia nigra (Hartig) which causes black snow mould. Depending on the amount of infestation, the damage can be limited to scattered groups or consist of large areas of dead seedlings. The fungus is unable to infect the plants during warm months of the growing season. The most damaging parasitic fungus in Scots pine is Phacidium infestans (Karst.) causing snow blight. The infestation varies from reddish-brown patches of infected seedlings to large areas of infected plants. Also, Botrytis cinerea has been determined from one- and two-year plants of pine and spruce.

In trials of chemical control by PCNB (pentachloronitrobenzene) gave nearly complete control of low-temperature parasitic fungi in one-year spruce seedlings. In addition, a compound of zineb (Dithane Z-78) gave similar results. Chemical control of the fungi is now common in the nurseries.

The PDF includes a summary in English.

  • Jamalainen, E-mail: ej@mm.unknown (email)
article id 4693, category Article
Martti Nenonen, Juhani Jukola. (1960). Tukkimiehen täin (Hylobius abietis L.) tuhoista mäntytaimistoissa ja niiden torjunnasta DDT :n avulla. Silva Fennica no. 104 article id 4693. https://doi.org/10.14214/sf.a9132
English title: Pine weevil (Hylobius abietis L.) injuries and their control by DDT in Scots pine seedling stands.
Keywords: Pinus sylvestris; soil preparation; Scots pine; planting; Hylobius abietis; insecticides; seedling damages; insect damages; DDT
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to find out more about pine weevil (Hylobious abietis L.) injuries in Scots pine (Pinus sylvestris L.) seedling stands and their control by means of DDT. For this purpose, inventories were made of seedling stands established earlier. Control experiments were made on burnt areas by planting seedlings dipped in a DDT emulsion.

The results of the inventories show that injuries caused by pine weevils can, in certain circumstances, especially in seedling stands established by planting, cause the complete failure in artificial regeneration. The extent and quality of the injuries vary greatly according to planting method, treatment of the cutting area, age of the seedling stand, environmental factors, and weather conditions. The most extensive injuries occur in regeneration areas of old Norway spruce stands burnt after clear cutting and planted with Scots pine seedlings. Injuries are greater in seedling stands established by planting, especially after broadcast burning, than in seedling stands originating either from artificial or natural seeding. The quality of the patch for sowing or planting has a considerable effect on the quantity and character of the injuries: in a patch from which organic matter has been removed, injuries do not appear or they are slighter. Seedlings can be protected effectively and economically by dipping their tops up to the root collar, in a DDT emulsion before planting.

The PDF includes a summary in English.

  • Nenonen, E-mail: mn@mm.unknown (email)
  • Jukola, E-mail: jj@mm.unknown
article id 4676, category Article
Gustaf Sirén. (1958). Eräitä havaintoja keskisuomalaisen ja paikallisen mäntyrodun biologisista ja teknillisistä ominaisuuksista Perä-Pohjolassa. Silva Fennica no. 96 article id 4676. https://doi.org/10.14214/sf.a9122
English title: Biological and technical properties of the local Scots pine and proveniences of Central Finland in Northern Finland.
Original keywords: Pohjois-Suomi; mänty; Pinus sylvestris; kasvu; alkuperä; tuotos; taudinkestävyys; provenienssi; Keski-Suomi
English keywords: Scots pine; northern Finland; growth; resistance; provenience; pathogen resistance; disease resistance; Central Finland
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to find out if it is possible to use Scots pine (Pinus sylvestris L.) seed from Central-Finnish origin in Northern Finland to supplement supply of local seeds. The principle has been to limit transfer of seeds to 200 km. According to this study, it seems possible to permit 300-400 km transfer of seeds at the same height above the sea level, not including the timber line area.

The author’s observations indicate that the trees originating from seeds of Central Finland at 20-35 years age withstand damage caused by snow and pine blister rust as well as the local provenience. However, the seedlings seem to be more susceptible to snow blight. Spraying of 2-3% sulphurated lime in the autumn before the arrival of snow proved to be most effective way to prevent the damage.

Southern proveniences have been found to grow faster than the local proveniences in Northern Finland. The stands of Tuomarniemi (Central Finland) and Rovaniemi (Northern Finland) provenances had no distinct difference in the summerwood percentage, and the volume weight of the Tuomarniemi provenience was higher than the weight of the provenience of Rovaniemi. The Tuomarniemi stand also gave largest yield, but the difference was probably due to partly at age difference of the sample trees. The naturally regenerated local provenance showed the greatest volume weight.

The article includes a summary in English.

  • Sirén, E-mail: gs@mm.unknown (email)
article id 4649, category Article
E. A. Jamalainen. (1956). Männyn karisteen torjunta kemiallisilla aineilla Leksvallin taimitarhassa. Silva Fennica no. 88 article id 4649. https://doi.org/10.14214/sf.a9110
English title: The control of needle cast of Scots pine with chemicals at the Leksvall nursery.
Original keywords: mänty; Pinus sylvestris; taimitarha; torjunta-aineet; männynkariste; männynharjakka; karisteet; sienitauti; Lophodermium; Peridermium pinastri; fungisidit
English keywords: Scots pine; fungicides; fungi; needle cast; pathogenic fungi; pathogen
Abstract | View details | Full text in PDF | Author Info

In 1953 and 1954 needle cast (Peridermium pinastri (Shrad.) Chev., now Lophodermium) caused much damage at the Leksvall nursery at Tammisaari as well as at some other nurseries in Southern Finland.

Experiments were conducted at the Leksvall nursery with different fungicides. The results showed that with spraying done every second week during the whole growing season beginning on May 20th and ending on 27th September in 1954, the damage caused by needle cast was entirely controlled with 2% Bordeaux mixture and the zineb preparation (Dithane Z-78); nabam preparation (Dithane D-14) being somewhat less effective. Lime sulphur, Burgundy mixture, thiram preparation, captan preparation, and PCNB preparation were rather ineffective, in addition, of these the lime sulphur and the Burgundy mixture caused damage to the needles. Phenylmercury preparation proved useless.

The article includes an abstract in English.

  • Jamalainen, E-mail: ej@mm.unknown (email)
article id 4648, category Article
Paavo Yli-Vakkuri. (1955). Männyn kylvötaimistojen hirvivahingoista Pohjanmaalla. Silva Fennica no. 88 article id 4648. https://doi.org/10.14214/sf.a9111
English title: Elk damage in seedling stands of Scots pine in Ostrobothnia.
Original keywords: mänty; Pinus sylvestris; taimituhot; hirvi; hirvituhot; Alces alces; Pohjanmaa; kylvötaimikot
English keywords: Scots pine; moose; seedling stands; seeding; elk; seedling damages; elk damages
Abstract | View details | Full text in PDF | Author Info

The article reviews the occurrence of damage causes by elk (Alces alces L.) in young Scots pine (Pinus sylvestris L.) stands established by direct seeding in the Ostrobothia region in Finland. The data was collected by random sampling, and consists of 110 sample plots in pine stands, established in 1930-1944.

Signs of elk damages could be observed in 20% of the stands. In more than half of the damaged stands pine seedlings were damaged by elk, on the rest of the stands the damage was targeted to hardwood saplings only. With the present density of elk population, the damage has an insignificant bearing upon the development of pine seedling stands in Ostrobothnia. The weaknesses of silvicultural state of the stands have been caused by other factors than elk.

Silviculturally weak stands were more liable to elk damage than strong ones. The occurrence of elk damage was more usual in stands with hardwood mixture than in pure pine stands. Especially goat willow, mountain ash and aspen, but also to some decree birch, seem to attract elk. Those factors that promote hardwood growth: fertility of the site, swampiness and the presence of seeding hardwoods in the area, increase the stand’s liability to elk damage.

The article includes an abstract in English and a summary in Swedish.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 4644, category Article
Vilho Antero Kolehmainen. (1955). Havaintoja kulotuksen merkityksestä metsiemme uudistamisessa. Silva Fennica no. 85 article id 4644. https://doi.org/10.14214/sf.a9106
English title: Effect of prescribed burning in the forest regeneration.
Original keywords: luontainen uudistaminen; kulotus; metsänuudistaminen; taimettuminen; siemenpuu
English keywords: Pinus sylvestris; Norway spruce; Picea abies; natural regeneration; Scots pine; Betula sp.; seed trees; prescribed burning
Abstract | View details | Full text in PDF | Author Info

Prescribed burning has reported to avail forest regeneration, for instance, by releasing nutrients for the use of seedlings, changing the pH of the soil and decreasing competition of ground vegetation. The aim of the study was to find out if the effects could be verified. Sample plots were measured in the experimental area of Tuomarniemi, in Central Finland, both in previously burned and untreated seedling stands and young forests. The main species in the sample plots was Scots pine (Pinus sylvestris L.).

According to the results, prescribed burning prepares the soil for regeneration. Germination percentage of the seeds is higher on the burned soil. All the species, Scots pine, Norway spruce (Picea abies (L.) Karst.) and birch species (Betula sp.) grow faster. Prescribed burning increases the amount of birch seedlings by improving its regeneration compared to unburned sites. The seed trees survive burning better if they are tall and have short crown, and have thick bark. In general, prescribed burning improves regeneration in seed tree stands.

The article includes a summary in German.

  • Kolehmainen, E-mail: vk@mm.unknown (email)
article id 4628, category Article
Gustaf Sirén. (1952). Havaintoja Peräpohjolan valtion mailla vuosina 1948-50 suoritetuista männyn kylvöistä. Silva Fennica no. 78 article id 4628. https://doi.org/10.14214/sf.a9100
English title: Observations on stands of Scots pine sown in state forests in Peräpohjola in northern Finland in 1948-50.
Original keywords: Pohjois-Suomi; valtionmetsät; kylvö; mänty; metsänviljely; Peräpohjola; uudistuminen
English keywords: Pinus sylvestris; regeneration; Scots pine; northern Finland; state forests; sowing
Abstract | View details | Full text in PDF | Author Info

The most common way to artificially regenerate cutting areas in Northern Finland has been sowing, which has, however, often given poor results. The aim of the study was to assess the success rate of sowing and study the causes of poor regeneration.

An inventory was made of 28 areas on Empetrum-Myrtillus and Hylocomnium-Myrtillus type sites sown with Scots pine (Pinus sylvestris L.) seeds in 1948-1950. In addition, to study the effect of substrata, a sowing experiment was established. According to the inventory, regeneration failed completely in 8 and partially in 6 of the 28 sown areas. Factors that explained the poor regeneration included unfavourable weather conditions in 1948-1952, insufficient clearing of sowing spot especially when the humus layer was thick, and insect damage by Otiorynchus dubius weevil.

The article includes a summary in English.

  • Sirén, E-mail: gs@mm.unknown (email)
article id 4613, category Article
Veijo Heiskanen. (1951). Mäntysahatukkien laatuarvioinnin tarkkuudesta. Silva Fennica no. 69 article id 4613. https://doi.org/10.14214/sf.a14009
English title: Accuracy of quality grading of Scots pine saw logs.
Original keywords: metsäopetus; mänty; metsänhoitajien jatkokurssit; puukauppa; jatkokoulutus; sahatukit; laatuluokitus; mäntytukki
English keywords: Pinus sylvestris; Scots pine; saw logs; forest education; quality grading; quality classes
Abstract | View details | Full text in PDF | Author Info

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation discusses accuracy of the quality grading of Scots pine (Pinus sylvestris L.) saw logs suggested by professor Ilmari Vuoristo based on a data collected by Valtiala. According to the study, greatest inaccuracies in the grading by visual inspection was caused by differences between the evaluators.

  • Heiskanen, E-mail: vh@mm.unknown (email)
article id 4612, category Article
Veijo Heiskanen. (1951). Mäntysahatukkien laadun mukaisista arvosuhteista. Silva Fennica no. 69 article id 4612. https://doi.org/10.14214/sf.a14008
English title: Value grading of Scots pine saw logs.
Original keywords: metsäopetus; mänty; metsänhoitajien jatkokurssit; sahatavara; jatkokoulutus; sahatukit; laatuluokitus; hinnoittelu
English keywords: Pinus sylvestris; Scots pine; saw logs; sawn timber; forest education; quality grading; sawn wood; timber grading
Abstract | View details | Full text in PDF | Author Info

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

Quality grading has been rarely used in pricing of saw logs due to lack of knowledge on how the quality of logs affects the value of the sawn wood. This presentation discusses the subject based on unpublished data professor Ilmari Vuoristo collected in 1930s on effects of timber grading on the quality and value of sawn wood. The quality classification developed by professor Vuoristo is presented.

  • Heiskanen, E-mail: vh@mm.unknown (email)
article id 4600, category Article
Aarne Nyyssönen. (1950). Vertailevia havaintoja hoidettujen ja luonnontilaisten männiköiden rakenteesta ja kehityksestä. Silva Fennica no. 68 article id 4600. https://doi.org/10.14214/sf.a9091
English title: Comparative study on structure and development of managed and natural Scots pine stands.
Original keywords: hakkuut; mänty; Pinus sylvestris; harvennushakkuu; kasvupaikkatyyppi; harvennus; luonnometsä; alaharvennus; läpimitan kasvu; tilavuuskasvu; latvuskerros
English keywords: natural forest; Scots pine; thinnings; diameter growth; fellings; increment; thinning from below; forest type; crown storey; tree classification
Abstract | View details | Full text in PDF | Author Info

The Forest Research Institute of Finland has established permanent sample plots to survey the effect of thinnings on the stands. This study compares the development of tended and natural Scots pine (Pinus sylvestris L.) stands growing on three different forest types: Oxalis-Myrtillus, Vaccinium and Calluna site type. The effect of heavy thinning from below (Oxalis-Myrtillus and Vaccinium site types) and increment felling (Calluna site type) was assessed by dividing the trees of the stands in tree classification classes according to their crown storey and defects.

The results show that thinning from below and increment thinning increase the proportion of trees in the 1st crown storey, which is already large in the natural stands. Also the diameter distribution is more even and the mean diameter higher after the thinnings.

In Scots pine stands in natural state, volume increment per stem is highest in the 1st crown storey and diminishes strongly towards the lower crown storeys. Thinnings increased the increment. The study indicates that many of the objectives of the intermediate cuttings, including promoting the growth of the best trees and improving the quality of the stand, have in general been achieved. Consequently, the thinnings give means to achieve the most valuable yield in the stand.

The article includes a summary in English.

  • Nyyssönen, E-mail: an@mm.unknown (email)
article id 4579, category Article
Reino Kalliola. (1942). Pyhätunturin kansallispuiston kasvillisuudesta ja kasvistosta. Silva Fennica no. 59 article id 4579. https://doi.org/10.14214/sf.a9083
English title: Vegetation and flora in the Pyhätunturi National Park.
Original keywords: luonnonsuojelualue; kuusi; kasvillisuus; mänty; kasvillisuuskartoitus; Lappi; kansallispuisto; Pyhätunturi; puuraja; tunturikoivu
English keywords: Pinus sylvestris; Norway spruce; Picea abies; vegetation; Scots pine; Lapland; nature reserve; national park; Pyhätunturi; vegetation survey; vascular plant; fell birch; Betula pubescens subsp. Czerepanovii); timber line
Abstract | View details | Full text in PDF | Author Info

The article is based on the writer’s visits in the area in 1933 and 1939. Pyhätunturi national park was established in 1938. The fell of Pyhätunturi rises up to 540 meters above the sea level, and 357 meters above the surrounding area. The soil is predominantly stony, and the rock is quartzite. The climate is continental with low rainfall. This results in a barren area, where array of plant species is limited with the exception of few gorges with fertile river valleys. The forests have remained mostly in natural state.

Vegetation is arranged in three zones: forested area, subalpine fell birch area and alpine bare top of the fell. Scots pine (Pinus sylvestris L.) forms timberline more often than Norway spruce (Picea abies (L.) H. Karst.). Coniferous forests rise up to 365 meters on the northern slopes and up to about 385 on the southern slopes of the fell. It is followed by fell birch zone (Betula tortuosa, now Betula pubescens subsp. Czerepanovii) up to about 450-475 meters on the eastern and northern slopes, and 475-490 meters on the western slopes. The most common forest site type is Empetrum-Myrtillus site type. Herb-rich spruce swamps along the rivers have highest diversity of species. The article describes the plant species found in forests, peatlands, fell birch zone and top of the fell in detail. In all 162 different vascular plant species and 16 non-indigenous species were found in the area.

The article includes an abstract in German.

  • Kalliola, E-mail: rk@mm.unknown (email)
article id 4479, category Article
L. E. T. Borg. (1936). Hankikylvöt Tuomarniemen hoitoalueessa vv. 1913-1930. Silva Fennica no. 38 article id 4479. https://doi.org/10.14214/sf.a9065
English title: Areas broadcast sown on snow in Tuomarniemi district in Finland in 1913-1930.
Original keywords: kuusi; Picea abies; kylvö; euroopanlehtikuusi; kylvömenetelmät; hankikylvö; Larix decidua; mänty; metsänviljely; Pinus sylvestris
English keywords: Norway spruce; sowing; broadcast sowing on snow; Socts pine; artificial regeneration
Abstract | View details | Full text in PDF | Author Info

Broadcast sowing on snow was relatively new method in the beginning of the 20th century in Finland, and the experiences of regeneration were diverse. The aim of the survey was to study the success rate of regeneration in the oldest and largest areas regenerated with this sowing method in Tuomarniemi district. Scots pine (Pinus sylvestris L.) was the most common tree species, but also Norway spruce (Picea abies (L.) H. Karst.) and European larch (Larix decidua Mill.) were used in broadcast sowing on snow.

According to the study, the success of broadcast sowing on snow was as good as patch sowing and sowing in furrows in the sites typical for Tuomarniemi. The regeneration areas were often drained peatlands or paludified lands. When sowing is done using Norway spruce seeds, site preparation either by broadcast burning or scalping with hoe is recommended. Mixed sowing with pine and spruce seldom succeeded due to the differences in site requirements of the species and growth of seedlings. Sowing of Scots pine succeeded well on the drained peatlands. Sowing should be done some years after draining to let the peat dry and sink. Site preparation is needed in sites growing Polytrichum-moss. Broadcast burned areas larger than 10 hectares seemed to regenerate poorer than sites in average, possibly due to dryness of the sites. Trials with European larch were successful, and the growth of the seedlings acceptable despite the sites being relatively poor for the species.

The PDF includes a summary in German.

  • Borg, E-mail: lb@mm.unknown (email)
article id 4435, category Article
Lauri Ilvessalo. (1926). Metsien säilymisen turvaaminen Karjalan kannaksen Suomenlahden rannikolla. Silva Fennica no. 2 article id 4435. https://doi.org/10.14214/sf.a8383
English title: Ensuring preservation of forests on the coast of Gulf of Finland in the Karelian Isthmus.
Original keywords: Etelä-Suomi; metsien hävittäminen; männikkö; ylihakkuu; metsänkäyttö; hakkuut
English keywords: Pinus sylvestris; Scots pine; deforestation; forest utilization; Southern Finland; overcutting; fellings
Abstract | View details | Full text in PDF | Author Info

Metsähallitus (Forest Service) commissioned a study about condition of forests on the coast of Gulf of Finland in the Karelian Isthmus. The study was made because of a growing concern on overcutting of the private forests in the area. Dominant tree species in the area is Scots pine (Pinus sylvestris L.). In fresh mineral soil sites Norway spruce (Picea abies (L.) H. Karst.) grows in mixed forest with pine or as pure stands. The forests are in average 50 to 70 years old. Younger or older stands are less frequent.

At the beginning of 18th century the local peasants sold plots for Russians, and a villa area was created along the coast. When Finland became independent, many of the properties changed owners. Timber harvesting of the forests increased and many small sawmills increased the demand of wood. Because of the cuttings, productivity of the forests decreases and danger for wind damage in the forests increases.

The author suggests that legislation created to prevent deforestation as well as counselling should be applied to improve forest management. In addition, a protective area should be formed in the Karelian Isthmus where forest preserving directives should be followed.

A summary in German is included in the PDF.

  • Ilvessalo, E-mail: li@mm.unknown (email)

Category : Article

article id 7173, category Article
Erkki Lähde. (1966). Studies on the respiration rate in the different parts of the root systems of pine and spruce seedlings and its variations during the growing season. Acta Forestalia Fennica vol. 81 no. 8 article id 7173. https://doi.org/10.14214/aff.7173
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; seedlings; respiration; seasonal variation; respiration of roots; respiration rate; short-roots; long-root
Abstract | View details | Full text in PDF | Author Info

In this study an attempt was made to use manometric Warburg technique in studying the growing season variations in the respiration rates of the roots of 1–3-year-old seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.). The respiration rates in both short-roots and long-roots have also been investigated.

According to the results, respiration intensity was the greatest in Scots pine and Norway spruce short-roots but also considerable in the long-root tips at the points of elongation. When the oxygen uptake rate per weight unit in the pine short-roots is given value of 100, the rate in the long-root tips is 61 and in the basal area 36. The corresponding values for spruce are 100, 69 and 43. The relative carbon dioxide release rates are different for the basal parts of the long-roots: pine 53 and spruce 57, when the CO2 release from the short-roots is 100. The CO2 release rate in the basal parts of the long-roots is relatively greater than the oxygen uptake. The respiration rate of the root systems of pine was larger than that of spruce due to the larger size of the root system.

The respiration rate per unit weight of pine roots of the 1- to 3-year-old seedlings decreases significantly with the increasing age. In spruce, the decrease was smaller. The result could have been different if only the short-roots of the same growing season were studied from all seedlings.

During the first growing season the root respiration rate decreased from the middle of the summer towards autumn. An experiment with pine seedlings grown in the mineral soil showed a very rapid increase in respiration rate in the spring. The rate, especially oxygen uptake, is at its greatest in the roots at the time of fastest growth.

  • Lähde, E-mail: el@mm.unknown (email)
article id 7170, category Article
Yrjö Ilvessalo. (1967). Luonnonnormaalien metsiköiden kehityksestä Kainuussa ja sen lähiympäristössä. Acta Forestalia Fennica vol. 81 no. 5 article id 7170. https://doi.org/10.14214/aff.7170
English title: The development of natural normal forest stands in southeastern Northern Finland.
Original keywords: kuusi; metsätyypit; mänty; kasvu; tuotos; luonnonnormaalit metsät; Kainuu
English keywords: Pinus sylvestris; Norway spruce; Picea abies; yield; Scots pine; northern Finland; growth; forest types; natural stands; natural normal stands
Abstract | View details | Full text in PDF | Author Info

Examination of stands developed under natural conditions can be used to provide basis for comparison for study of the development and yield of stands treated with intermediate fellings. In Finland, the first investigation and the yield and the structure of natural normal stands were published in 1920. This investigation on development and yield of the natural forests of Kainuu in southeastern Northern Finland is based on 92 sample plots on three forest types; Empetrum-Vaccinium type (EVT), Empetrum-Calluna type (ECT) and Vaccinium-Myrtillus type (VMT).

The Scots pine (Pinus sylvestris L.) sample plots represented variation of age classes for construction of mean development series. The Norway spruce (Picea abies (L.) H. Karst.) of the region are so old that development series could be obtained only for dominant trees based on stem analysis.

The average development of Scots pine stand on EMT type within the region is on average more rapid and the yield in cubic volume quantitatively larger and structurally better than that on ECT type. Self-thinning during the early decades of EVT is slower. The pine stands are denser in the age of 70 in Kainuu compared to Central Northern Finland, but the development and yield are similar.

The development, yield and structure of natural Norway spruce stand on VMT proved considerably inferior to the average level of pine stands on EVT, and to a major part on ECT. The mixed pines on spruce sample plots have developed better than spruces of equal age. Spruce stands on VMT in the area developed markedly better than Geranium-Dryopteris-Myrtillus (GDMT) in Central Northern Finland.

It seems that a spruce stand seems to require more fertile site type in north than in the southern part of Finland. These fertile types are relative rare in the north. In the region, the best results are received with pine. As a rule, also the yield of birch (Betula sp.) is poor in the region.

The PDF includes a summary in English.

  • Ilvessalo, E-mail: yi@mm.unknown (email)
article id 7166, category Article
J. E. Hårdh. (1966). Trials with carbon dioxide, light and growth substances on forest tree plants. Acta Forestalia Fennica vol. 81 no. 1 article id 7166. https://doi.org/10.14214/aff.7166
Keywords: Pinus sylvestris; Betula pendula; Picea abies; Scots pine; silver birch; seedlings; carbon dioxide; growth hormones; growth studies; tree nursery; Norway sprce
Abstract | View details | Full text in PDF | Author Info

Growth-promoting effects of enhanced caron dioxide levels upon forest tree seedlings grown in plastic houses was studied in 1964 and 1965 in the Forest Breeding Foundation in Haapastensyrjä near Loppi in Southern Finland. In both years more vigorous height and weight growth, and development of root system was achieved when the CO2 concentration was increased to 0.2% than in the normal conditions (CO2 0.03%). The CO2 concentration was increased by burning propane in the plastic houses. Burning continued for four hours per day either at 8–10 and 14–16 a clock or 6–10 a clock. Growth was not affected by the time of the treatment, and it was equally high in 0.1% and 0.2% concentrations.

Treatment of the seedlings with 100–200 ppm gibberellic acid (GA) increased the height growth of healthy, well-rooted seedlings. Treatment with a concentrated (600 ppm) dosage, as well as treatment with a combination of GA and 1-naphtyl acetic acid (NAA) caused serious defects in grafts of Scots pine (Pinus sylvestris L.). GA treatments did not induce flower formation in pine. Red light during the night seemed to enhance growth of grafts of silver birch (Betula pendula Roth) and Norway spruce (Picea abies (L.) H. Karst.).

The PDF includes a summary in Finnish.

  • Hårdh, E-mail: jh@mm.unknown (email)
article id 7164, category Article
Veijo Heiskanen. (1965). Puiden paksuuden ja nuoruuden kehityksen sekä oksaisuuden ja sahapuulaadun välisistä suhteista männiköissä. Acta Forestalia Fennica vol. 80 no. 2 article id 7164. https://doi.org/10.14214/aff.7164
English title: Relation between the development of the early age and thickness of trees and their branchiness in Scots pine stands in Finland.
Original keywords: tiheys; mänty; laatupuu; tyvitukki; oksaisuus; kasvatustiheys; laatukasvatus
English keywords: Pinus sylvestris; Scots pine; density; quality; stand density; branchiness; knottiness; butt log; quality timber
Abstract | View details | Full text in PDF | Author Info

The objective of the study was to establish the influence of the founding density of a stand and the intensity of intermediate cutting on the quality of pine saw logs stems, primarily on their branchiness. Measurements were carried out in 68 Myrtillus-type and 32 Vaccinium-type Scots pine (Pinus sylvestris L.) stands. The quality of 1,982 sample trees was assessed.

According to the results, the branchless part of the stem is longest in the older age classes of trees. In all age classes the percentage of the branchless part is highest in medium sized stems. The relative height of the crown limit is greatest in small diameter classes and continues as the thickness of the tree increases. The crown is longer in the thicker tree. The grade of the butt log is on average highest in medium sized stems. Knottiness of a log made it unsuitable for a saw log only among the thickest stems. The relative share of the u/s grade decreased as the thickness of the trees increased.

From the point of view of early development of the trees it was concluded that in all age classes the branchless part is the shorter the faster the tree has grown in diameter when it was young. Also, branches of the butt log are the bigger the faster the tree has developed when it was young. The grade of the butt log improves as the thickness of the annual rings diminishes.

To produce good quality sawn timber, the pine stands should be established dense, and the first thinnings should be delayed as much as possible. The best time for the thinning would be when the diameter of the dominant trees at stump height is 12–15 cm and when all the branches have died on the length of the butt log. After the first thinning, comparatively intense intermediate thinning may be applied.

The PDF includes a summary in English.

  • Heiskanen, E-mail: vh@mm.unknown (email)
article id 7161, category Article
Olavi Laiho. (1965). Further studies on the ectendotrophic mycorrhiza. Acta Forestalia Fennica vol. 79 no. 3 article id 7161. https://doi.org/10.14214/aff.7161
Keywords: Pinus sylvestris; Scots pine; Finland; tree species; distribution; Europe; ecology; mycorrhiza; seedlings; tree nurseries; occurrence; America
Abstract | View details | Full text in PDF | Author Info

There has not been complete agreement as to what is meant by ectendotrophic mycorrhizae, and there is a wide variety of opinion among authors on mycorrhizal terminology. In this paper ectendotrophic mycorrhizae are defined to be short roots with Hartig net and intracellular hyphae in the cortex. A mantle and digestion of intracellular hyphae may be found but are not necessary. In the study of Mikola (1965) ectendotrophic mycorrhiza was found to be common in Scots pine (Pinus sylvestris L.) seedlings in Finnish nurseries. The mycorrhizae had always similar structure and the mycelium isolated from the seedlings (E-strains) was similar. The aim of this study was to find out what kind of ectendotrophic mycorrhizae exist in forests and nurseries outside Finland, what kind of mycorrhizae do the E-strains isolated from Scots pine form with other tree species, and are these associations symbiotic.

Only one type of ectendotrophic mycorrhiza was found on the 600 short roots collected from the continents of Europa and America. The type was similar to the one described by Mikola: the mycelium is coarse and forms a strong Hartig net, and intracellular infection is heavy. Evidence is convincing that this structure was formed by the same fungus species. The species is unidentified. Mycorrhizae synthesized by E-strain with six spruce species, fir, hemloch and Douglas fir were all ectotrophic.

The E-type ectendotrophic mycorrhizae proved to be a balanced symbiosis. The seedlings of 13 tree species inoculated with the E-strain grew in the experiment better than the controls. The observation that ectendotrophic mycorrhizae dominates in the nurseries but is seldom found in forests, and then only in seedlings growing in the forest, was confirmed in the study. In synthesis experiments E-strain formed either ecto- or ectendotrophic mycorrhiza depending on the tree species.

  • Laiho, E-mail: ol@mm.unknown (email)
article id 7160, category Article
Peitsa Mikola. (1965). Studies on the ectendotrophic mycorrhiza of Scots pine in Finland. Acta Forestalia Fennica vol. 79 no. 2 article id 7160. https://doi.org/10.14214/aff.7160
Original keywords: mänty; taimet; mykorritsa; ektendomykorritsa; esiintyminen
English keywords: Pinus sylvestris; Scots pine; Finland; mycorrhiza; seedlings; tree nurseries
Abstract | View details | Full text in PDF | Author Info

The differences between different types of mycorrhiza; endomycorrhiza, ectomycorrhiza and ectendomycorrhiza, and the use of the terms have been variable in the earlier research. Studied of mycorrhiza in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seedlings may suggest that the conditions affect which kind of mycorrhiza develops in the seedlings. This study is aimed mainly at finding out whether the difference of ectotrophic and ectendotrophic mycorrhizae depends on fungal symbionts or envirionmental conditions. Furthermore, the occurrence of ectendotrophic mycorrhiza in Finland under various conditions was studied, and experiments on the physiology and ecology of the mycorrhiza and the fungal partner were conducted.

The ectendotrophic mycorrhiza as described in this paper has proved to be very common on Scots pine in Finnish nurseries, but it was not found in Norway spruce seedlings. The results did not support the hypothesis presented in some earlier studies that ectendotrophic mycorrhiza is more parasitic than the other mycorrhizal fungi. The nursery survey showed that no correlation existed between the size and vigour of the seedlings and the presence of ectendotrophic mycorrhiza. Furthermore, greenhouse-grown seedlings with and without the fungus grew equally well. The type of mycorrhiza was, however, almost exclusively confined to young (1–3-years-old) seedlings and to nursery soils. The experiments indicates also that ectendomycorrhizal fungus has a very wide ecological amplitude in regard to light intensity, soil fertility, acidity, and humus content. It has, however, a weak competitive ability in natural forest soils against the indigenous fungal population. When the seedlings were transplanted from the nursery to forest soil, their mycorrhizal population was largely changed.

  • Mikola, E-mail: pm@mm.unknown (email)
article id 7158, category Article
Olavi Huuri. (1965). Männyn- ja kuusenkäpyjen varastoinnin vaikutus niistä saatavan siemenen itävyyteen. Acta Forestalia Fennica vol. 78 no. 5 article id 7158. https://doi.org/10.14214/aff.7158
English title: The effects of storage in cones on the viability of pine and spruce seeds.
Original keywords: kuusi; mänty; itävyys; kävyt; siemenkeräys; käpyjen varastointi; metsäpuiden siemenet; siementen varastointi; karistus; itämiskyky
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; cones; seeds of forest trees; seed extraction; storage of cones; storage of seeds; germinative capacity
Abstract | View details | Full text in PDF | Author Info

Seed storing experiments with cones of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) were conducted in Oitti seed extracting plant in Southern Finland from February to December 1955. The pine cones were stores for 267 and the spruce coned for 304 days. In four of the storage methods the cones were packed in sacks and another four in wooden boxes. Sample of cones were taken once a month, seeds were extracted and the germinative capacity was tested. The remaining extracted seeds were placed in storage, and in January 1956 moved to cold seed cellar until 1962, when the viability of the seeds was tested.

According to the results, cleaned pine cones can be stores for at least nine months using almost all methods of storage which are commonly used at our seed traction plants, without hazarding the usability of the seeds. The seeds in spruce cones, however, seemed to be more sensitive to conditions during the storage. The germinative capacity of the spruce seeds began to decrease after the beginning of May. Later the seeds were infected with mould, which increased towards the end of the experiment.

Thus, preservation of the germinative capacity of the seeds of pine and spruce requires storage in different conditions. The results suggest that extraction of spruce seeds should be finished during the cold winter months. It seems that seed in the cones of pine and spruce endure storage in piles of paper or cloth sacks at least as well as in wooden boxes. Occasional warming of the storage, snow and foreign material among the cones and an over meter thick cone layer decreased the germinative capacity of spruce seeds during spring and summer. Spruce seeds that had been extracted immediately after collecting of the cones preserved their germinative capacity well during an eight years storage period.

The PDF includes a summary in English.

  • Huuri, E-mail: oh@mm.unknown (email)
article id 7157, category Article
Leo Heikurainen, Kustaa Seppälä. (1965). Regionality in stand increment and its dependence on the temperature factor on drained swamps. Acta Forestalia Fennica vol. 78 no. 4 article id 7157. https://doi.org/10.14214/aff.7157
Keywords: Pinus sylvestris; Norway spruce; Picea abies; drained peatlands; Scots pine; growth; increment; regional increment; stand quality
Abstract | View details | Full text in PDF | Author Info

The aim of this work was to study, on the basis of material published earlier (Heikurainen 1959), the effect of temperature on stand increment, to find out if there is any differences between Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.), and to study the effect of site quality on the relationship between stand increment and temperature. The calculations were based on data collected from 396 sample plots on drained peatlands in different parts of Finland.

There seemed to be no differences due to tree species or site quality in the relative amounts of growth under different climatic conditions. Thus, differences in the absolute growth between poor and fertile sites are noticeably smaller in Northern Finland than in Southern Finland. The author suggests that this implies that the lasting maximal increase of growth which can be produced, for instance, by using soil-improving agents must be less in unfavourable conditions than in favourable.

  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Seppälä, E-mail: ks@mm.unknown
article id 7156, category Article
Tauno Kallio. (1965). Tutkimuksia maannousemasienen leviämisbiologiasta ja torjuntamahdollisuuksista Suomessa. Acta Forestalia Fennica vol. 78 no. 3 article id 7156. https://doi.org/10.14214/aff.7156
English title: Studies on the biology of distribution and possibilities to control Fomes annosus in Southern Finland.
Original keywords: kuusi; mänty; juurikääpä; torjunta; kannot; ilmalevintä; itiöt
English keywords: Pinus sylvestris; Norway spruce; Picea abies; stumps; Scots pine; Heterobasidion annosum; root rot; fungicides; prevention; fungal pathogens; aerial infection
Abstract | View details | Full text in PDF | Author Info

The aim of this investigation was to clarify aerial infection of Fomes annosus (now Heterbasision annosum) in the cross-sections of stumps of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) in Southern Finland. In addition, an attempt was made to study possibilities to reduce an eventual aerial infection by means of spreading various protecting substances on the cross-section of the stumps immediately after cutting. The stumps were treated withs creosote, ceruse (lead white) and a product named ”Ventti”, which active constituent is copper. The effect of prescribed burning of the site on the aerial spreading of the fungus was studied.

Five sample plots were located in spruce stands and one in a pine stand. One of the spruce stands was prescribed burned. Samples were taken from the stumps 14–17 and 24–29 months after cutting. To identify the fungi, the samples were cultivated on a nutrient substrate in laboratory conditions. The results show that Heterobasidion annosum had spread by air to cross-sections of stumps of spruce. 11.5% of the samples taken from the spruce stumps 14–17 months and 17% of samples taken 24–29 months after cutting were infected. Burning of the site reduced strongly the aerial infection of stumps by the fungus. The stumps of Scots pine were not infected by Heterobasidion annosum in this study. The infection could be limited by treating the cross-sections with substances that are used to prevent growth of mould.

The PDF includes a summary in English.

  • Kallio, E-mail: tk@mm.unknown (email)
article id 7151, category Article
Peitsa Mikola, Olavi Laiho, Jorma Eerikäinen, Kari Kuvaja. (1964). The effect of slash burning on the commencement of mycorrhizal association. Acta Forestalia Fennica vol. 77 no. 3 article id 7151. https://doi.org/10.14214/aff.7151
Keywords: Pinus sylvestris; Scots pine; mycorrhiza; seedlings; prescribed burning; sowing
Abstract | View details | Full text in PDF | Author Info

Prescribed burning is a common silvicultural practice in northern Europe, intended to destroy the slash and ground vegetation and to reduce the thickness of the raw humus layer prior reforestation. The purpose of the experiments was to study whether there are any differences in the commencement and early development of mycorrhizal infection between burned and unburned areas. A clear-cutting area was burned on May 1961. The soil was rocky moraine, the forest type was Vaccinium type. Two weeks after burning Scots pine (Pinus sylvestris L.) was sown in patches.

According to the results, mycorrhizal infection took place on the unburned area earlier than on the burned. The difference was relatively small, perhaps 1–2 weeks. Although burning kills mycorrhizal fungi, it did not cause serious harm to the seedlings, on the contrary, the favourable influence of burning was more distinct. The high temperatures caused by the fire are restricted in the soil in a prescribed burning only a few centimetres deep. Although the mycorrhizal fungi are concentrated in a very thin surface layer of the soil, some mycorrhizae are situated deeper, and from there the fungi are able to infect roots and spread back to the surface layer. The fire also rises the pH of the soil, which can be harmful for mycorrhizal fungi. Even this effect, however, is limited to a thin surface layer.

The PDF includes a summary in Finnish.

  • Mikola, E-mail: pm@mm.unknown (email)
  • Laiho, E-mail: ol@mm.unknown
  • Eerikäinen, E-mail: je@mm.unknown
  • Kuvaja, E-mail: kk@mm.unknown
article id 7150, category Article
Olavi Laiho, Peitsa Mikola. (1964). Studies on the effect of some eradicants on mycorrhizal development in forest nurseries. Acta Forestalia Fennica vol. 77 no. 2 article id 7150. https://doi.org/10.14214/aff.7150
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; mycorrhiza; herbicide; seedlings; tree nurseries; eradicants; fungicide
Abstract | View details | Full text in PDF | Author Info

Mycorrhizal association is a characteristic feature of the trees of the northern coniferous forests. The purpose of the present study was to determine what influence some fungicides and herbicides regularly used in Finnish nurseries have on formation and development mycorrhizal in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seedlings. The results are based mainly on field experiments in nurseries. First the initiation of mycorrhiza was described in untreated seedlings.

In the first growing season mycorrhizal infection commences fairly late even under normal conditions, i.e. 6–7 weeks after seeding and 3–4 weeks after the formation of the first short roots. Soil disinfectants are commonly used in nurseries before seeding, and they are supposed to evaporate or disintegrate in a few days or 1–2 weeks. In pure culture experiments mycorrhizal fungi proved several times more sensitive than parasitic and indifferent soil moulds to herbicides and fungicides, but in field experiments the delay of mycorrhizal infection caused by them does not seem to harm the seedlings. In the second summer differences of mycorrhizal relations between treated and control plots disappeared. Accordingly, the influence of biocides on mycorrhizae, when applied in the customary concentrations, does not extend beyond the first growing season.

Methyl bromide and SMDC retarded mycorrhiza formation distinctly, while formaldehyde and allyl alcohol had no effect. Apart from not retarding mycorrhizae, formaldehyde and allyl alcohol promoted seedling growth and favoured Trichoderma viride in the soil. Trichoderma is known to be antagonistic to many fungi.

The PDF includes a summary in Finnish.

  • Laiho, E-mail: ol@mm.unknown (email)
  • Mikola, E-mail: pm@mm.unknown
article id 7148, category Article
Maunu Seppänen. (1964). Vesisateen jakautumisesta männiköissä. Acta Forestalia Fennica vol. 76 no. 8 article id 7148. https://doi.org/10.14214/aff.7148
English title: Distribution of rainfall in the Scots pine stand in Central Finland.
Original keywords: mänty; metsikkösadanta; runkovalunta; haihdunta; vesisade
English keywords: Pinus sylvestris; precipitation; stemflow; throughfall; rainfall
Abstract | View details | Full text in PDF | Author Info

Distribution of rainfall in in a Scots pine (Pinus sylvestris L.) stand and in an open place in Alajärvi in Central Finland was studies in 1959–1960. Density of the about 80 years old stand was 0.36 and the height of the trees 8–14 m. The dependence of throughfall and dependence of stemflow on 24-hour precipitation, and dependence of the distribution of 24-hour precipitation on the amount and nature of precipitation was calculated.

The precipitation of the crown of the forest depended on the rainfall. When the rainfall in the open place was over 7 mm, the rainfall within the forest was in average 89% of the rainfall in the open place, but if the rainfall in the open place was less than 1 mm, the rainfall within the forest was only 64% of that in the open place. Total stemflow in the pine stand was only 0.4%, and interception loss was 13.6%.

The PDF includes a summary in English.

  • Seppänen, E-mail: ms@mm.unknown (email)
article id 7135, category Article
Paavo Yli-Vakkuri. (1961). Kokeellisia tutkimuksia taimien syntymisestä ja ensi kehityksestä kuusikoissa ja männiköissä. Acta Forestalia Fennica vol. 75 no. 1 article id 7135. https://doi.org/10.14214/aff.7135
English title: Experimental studies on the emergence and development of tree seedlings in spruce and pine stands.
Original keywords: kuusi; kylvö; mänty; taimettuminen; uudistuminen; uudistaminen; itäminen
English keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; regeneration; Scots pine; seedlings; sowing; seeding; restocking with seedlings
Abstract | View details | Full text in PDF | Author Info

This paper aims at studying regeneration of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) by sowing and natural regeneration of birch (Betula sp.) in Western Finland.

Germination of spruce and pine seeds may be prevented by dryness and temperatures below the optimum for germination. In natural conditions, when temperature and moisture is insufficient for germination, the type of seedbed generally has en effect on germination result. Trenching of the seeding spots showed that root competition during the early stage of regeneration was not of decissive importance. It seemed to, however, improve the preservation of the seedlings later. It is common that it can take long before the seeds germinate, and during that time the number of viable seeds decrease strongly.

Also, the seedling stock quickly began to decrease in number after germination, especially during the first growing season and the following winter. The decrease was larger in intact vegetation than on mineral soil or in the humus layer. The emerging seedlings were destroyed by drought very easily, but their tolerance to drought improved later on.

The PDF includes a summary in English.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7130, category Article
Paavo Yli-Vakkuri. (1961). Tutkimuksia männyn kylvöalojen metsittymisvaiheesta. Acta Forestalia Fennica vol. 74 no. 3 article id 7130. https://doi.org/10.14214/aff.7130
English title: Studies on the development of young sown pine stands in Central Finland.
Original keywords: kylvö; mänty; taimikko; uudistaminen
English keywords: Pinus sylvestris; regeneration; Scots pine; seedling stand; sowing; seeding
Abstract | View details | Full text in PDF | Author Info

In this paper the development of sown Scots pine (Pinus sylvestris L.) seedling stands into forests is studied. The material was collected in stands sown in 1930–1940 in private forests in the Forestry Board districts of Central and Northern Ostrobothnia. The 119 areas, including both burned and other areas, were studied in 1955.

Most seedings had been carried out on relatively poor soils, mostly representing Vaccinium and Calluna type forests. 71% of the areas consisted of large forest fires, mostly from 1933. The most burned areas did not have seed producing trees nearby. The other sown areas were in general small, 1–2 ha, and near forests capable of producing seeds. The species of previous tree generation, in the older areas mostly pine and in the younger areas Norway spruce, affected tree species composition of the new tree generation.

Over 90% of the burned areas were in silviculturally good or satisfactory condition, while the main part of the other sown stands was in fair or poor condition. Weeding and thinning had been done only in the oldest stands. Most stands had been left untended. Natural new trees often competed with the sown pines, and cull-trees and border forest increased natural regeneration in the areas. In Calluna type the poor soil limited regeneration and growth of broadleaf trees. The worst competitors were naturally regenerated pine seedlings both on Calluna and Vaccinium type. On Vaccinium type also birch and sometimes also aspen (Populus tremula L.) competed with sown pine. On better sites and paludified areas competition by broadleaf trees increased. The rhythm of development of broadleaved trees is so different from pine that only those broadleaved trees that are formed in the stand when the pine seedlings are larger can develop harmoniously with pine. Due to the harmful competition, the seedling stands should be tended early on. In addition, it may be advisable to abandon the practise to leave trees on sowing areas.

The PDF includes a summary in Finnish.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7128, category Article
Paavo Yli-Vakkuri. (1961). Emergence and initial development of tree seedlings on burnt-over forest land. Acta Forestalia Fennica vol. 74 no. 1 article id 7128. https://doi.org/10.14214/aff.7128
Keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; regeneration; Scots pine; seeds; prescribed burning; sowing; seeding
Abstract | View details | Full text in PDF | Author Info

Prescribed burning has been used in regeneration areas in Finland as a method to treat the humus layer and creating more favourable chemical, physical and biological conditions for the seedlings. At the same time, fire clears away seedlings and shoots of unwanted trees and other vegetation. Direct sowing or planting, mostly Scots pine (Pinus sylvestris L.), seldom natural regeneration, is used. In this paper, the initial stages of the formation of a new tree generation of Scots pine and Norway spruce (Picea abies (L.) Karst.) on prescribed burned areas is studied in Central Finland in 1956–1960.

The burned area remains almost without vegetation for about two growing seasons. Conditions on a burned area which has not been tiled are very unfavourable for germination of seeds of coniferous and deciduous trees. On the other hand, shoots of deciduous trees occur soon after burning. Conditions for regeneration were found to be better 3–5 years after burning. Removal of humus layer in spots improved regeneration. However, the patches facilitated also natural regeneration of Norway spruce and especially birch (Betula sp.), which compete with Scots pine seedlings.

Continuous rainy periods improved the germination of Scots pine and Norway spruce seeds sown on the humus layer. Pine and spruce developed more rapidly on the exposed soil, however, young seedlings were easily destroyed. Seed eaters destroyed the pine and spruce seeds sown on the humus layer of newly burned areas completely or almost completely. The viability of pine seeds sown on the burned humus layer did not decrease for three weeks, but the viability greatly weakened after six or more weeks. Spruce seeds lost their viability faster than pine seeds.

The PDF includes a summary in Finnish.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7119, category Article
Paavo J. Ollinmaa. (1960). Eräistä ojitetuilla soilla kasvavan puun fysikaalisista ominaisuuksista. Acta Forestalia Fennica vol. 72 no. 2 article id 7119. https://doi.org/10.14214/aff.7119
English title: Physical properties of wood growing on drained peatlands.
Original keywords: kuusi; ojitus; mänty; puun laatu; turvekankaat; rauduskoivu; hieskoivu; puuaine; lujuus
English keywords: Pinus sylvestris; Norway spruce; Betula pendula; Picea abies; Betula pubescens; drained peatlands; Scots pine; wood; mechanical strength
Abstract | View details | Full text in PDF | Author Info

The objective of the investigation was to determine the differences between faultless timber grown on a peatland before and after draining, in respect of compressive strength to the grain, volume weight, and shrinkage. In addition, the influence of the boundary zone between the close-ringed wood formed before draining and the wide-ringed wood produced after draining on strength of the timber was studied. The material consisted of 15 sample trees of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.), white birch (Betula pubescens Ehrh.) and silver birch (B. Pendula Roth).

The volume weight of wood of the tree species in ascending order is; spruce, pine, white birch, silver birch. The volume weight of Scots pine seems to decrease from the butt end upwards, while no trend was revealed for spruce. In the coniferous trees, the wide-ringed wood formed subsequent to draining was slightly lighter than the close-ringed wood produced prior draining. No distinct trend was seen in the birch species. The volume weight of pine and spruce increased with decreasing width of the growth rings up to a certain limit, after which the conditions inverted.

The compressive strength of the different kinds of wood seems to increase from the butt end upwards, but after height of two meters it begins to decrease considerably. In birch, this point of inversion is in somewhat greater height. In spruce timber, the compressive strength parallel to the grain is lowest for wood which contains exclusively wide-ringed wood formed after draining. The boundary zone between the woods formed before and after draining is very distinguishable, but has no remarkable influence on the compressive strength parallel to the grain. Shrinkage of close-ringed wood is higher in all three principal directions than that of wide-ringed wood. This can be explained by the variations in volume weight and fibrillar orientation of the tracheid walls.

The PDF includes a summary in English.

  • Ollinmaa, E-mail: po@mm.unknown (email)
article id 7118, category Article
Paavo J. Ollinmaa. (1959). Reaktiopuututkimuksia. Acta Forestalia Fennica vol. 72 no. 1 article id 7118. https://doi.org/10.14214/aff.7118
English title: Study on reaction wood.
Original keywords: kuusi; mänty; havupuut; kataja; haapa; reaktiopuu; vetopuu; lujuus; leppä; kutistuminen; lehtipuut; lylypuu; ligniini
English keywords: Populus tremula; Pinus sylvestris; Norway spruce; Picea abies; Scots pine; compression wood; lignin; mechanical strength; Alnus incana; tension wood; shrinkage; Juniperus communis; raction wood; common juniper
Abstract | View details | Full text in PDF | Author Info

Compression wood of the tree species studied in this investigation, Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.) and common juniper (Juniperus communis L.), was found to be characterized in its cross section by the thick walls and rounded shape of its tracheids and the profuse occurence of spaces. Tension wood of aspen (Populus tremula L.) and alder (Alnus incana (L.) Moench) was found in microscopic examination to be characterized by the gelatinous appearance of the wood fibres, by its small cell cavities and by the thickness and buckling of the inner layer of the cecondary wall. Tracheids of the compression wood were found to have shorter length than normal on an average, while the tension wood fibres were found to be longer.

The microchemical studies suggest a higher than normal lignin content in compression wood and lower than normal lignin content in tension wood, as compared to normal wood. The reverse would be true for the cellulose contents. Volume weight of absolute dry reaction wood was distinctly higher than that of normal wood. The longitudinal shrinkage of reaction wood, particularly of compression wood, is several times that of normal wood. Transversal shrinkage of compression wood is much less than normal wood. Swelling tests revealed pushing effect of compression wood on elongation and pulling effect on tension wood on constraction. Volume shrinkage of compression wood is less than that of normal wood, in contrast to tension wood. The strength of compression wood in absolutely dry condition was nearly same as that of normal wood.

The PDF includes a summary in English.

  • Ollinmaa, E-mail: po@mm.unknown (email)
article id 7116, category Article
Kustaa Kallio. (1960). Metsikön taksatorinen tiheys keskipituuteen ja tiheyteen perustuvassa kuutiomäärän arvioinnissa. Acta Forestalia Fennica vol. 71 no. 7 article id 7116. https://doi.org/10.14214/aff.7116
English title: The mensurational density of a stand in estimating the volume on the basis of the mean height and the density class.
Original keywords: kuusi; mänty; kuutiomäärä; tilavuus; metsikön tilavuus; tilavuuden arviointi; keskitiheys; keskipituus; valtapituus
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; growing stock; volume; dominant height; estimation of volume; density class; mean height
Abstract | View details | Full text in PDF | Author Info

In Finland ocular estimation of the growing stock has been made by means of volume tables based on the mean height and density class, or on the dominant height and density class of the stand. The author has observed that if the volume of a stand is estimated by employment of both tables, the results vary markedly from one another. Furthermore, volume of fully stocked stands in the dominant height tables show an approximate correspondence with the volumes of managed normal stands in Southern Finland.

The purpose of this study is therefore to develop volume tables for coniferous trees, based on the density class and the mean height; these tables should give the same volume for a stand as the dominant height tables.

Volume per hectare of 187 Scots pine (Pinus sylvestris L.) stands and 120 Norway spruce (Picea abies (L.) Karst.) stands on different forest types were estimated using the relascope method in Southern Finland. With the volume and the measured mean and dominant heights as a basis, the density classes were extracted from both mean height tables and the dominant height tables. The investigation indicates that the author estimated the dense stands too thinly, and the thin ones too densely, and that the erroneous estimation of the density can be corrected by comparison of the ocular estimations and the corresponding measurements. The density can be measured by means of crown closure, stem number per hectare or the basal area per hectare.

The PDF includes a summary in English.

  • Kallio, E-mail: kk@mm.unknown (email)
article id 7114, category Article
Paavo Yli-Vakkuri. (1960). Metsiköiden routa- ja lumisuhteista. Acta Forestalia Fennica vol. 71 no. 5 article id 7114. https://doi.org/10.14214/aff.7114
English title: Snow cover and ground frost in Finnish forests.
Original keywords: kuusi; mänty; lumipeite; lumi; routa; lehtipuut; kasvuolosuhteet
English keywords: Pinus sylvestris; Norway spruce; deciduous trees; Picea abies; Scots pine; snow; growth conditions; snow cover; ground frost
Abstract | View details | Full text in PDF | Author Info

Snow cover and ground frost was studied in 29 forest stands in Southern and Central Finland in 1957–1959. The tree species influenced greatly accumulation of snow on the forest floor. Norway spruce (Picea abies (L.) Karst.) retains snow in its crown. In addition, snow and water falling from the branches compress the snow cover under the trees, and the ground freezes deeper because of the shallow snow cover. In the spring, the dense crown prevents rain and radiation reaching the ground, which remains cold longer. However, ground frost may protect spruce, which has a weak root system, from wind damages.

Scots pine (Pinus sylvestris L.) has similar, but milder, effects on snow cover within the forest. The crowns of pine seedlings and young trees pass snow easily, but later the crowns intercept it considerably. The lower branches are, however, high up and the snow is evenly spread on the ground. The deciduous trees intercept little snow and in the spring the snow smelts and the frozen soil thaws early. The snow conditions of deciduous forests are, however, changed by a spruce undergrowth.

It can be assumed that the unfavourable conditions in spruce forests can be alleviated by thinning. Also, mixture of pine and deciduous trees can transform the conditions more favourable in the spruce stands.

The PDF includes a summary in English.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7112, category Article
Kustaa Kallio. (1960). Etelä-Suomen kylvömänniköiden rakenteesta ja kehityksestä. Acta Forestalia Fennica vol. 71 no. 3 article id 7112. https://doi.org/10.14214/aff.7112
English title: Structure and development of Scots pine stands established by sowing in Southern Finland.
Original keywords: kylvö; kasvu; tuottokyky; uudistaminen; tuotto; kylvömännikkö
English keywords: Pinus sylvestris; yield; Scots pine; growth; sowing; increment; yield potential
Abstract | View details | Full text in PDF | Author Info

In Southern Finland Scots pine (Pinus sylvestris L.) is mainly sown on Vaccinium and Myrtillus-type sites. The material for the study was collected by measuring sample plots in pure, even-aged pine stand that had been sown. The sample stands had been thinned from below.

The volume of the stands was roughly the same as that of repeatedly thinned pine stands. The cubic volume of sown pine stands is 65–90%, varying according to age, of that of natural-normal pine stands. The current annual volume increment of stands on Myrtillus-type was 8–9 m3/ha at age of 20–30 years. The peak was reached at age of 35 years with 9 m3/ha, in the following years the increment is about 8 m3/ha until the age of 60 years. On Vaccinium type sites increment reaches 6–7 m3 level at age of 30 years, and attains the peak of 7 m3/ha at the age of 45 years. Annual increment was in young and middle-aged Myrtillus-type stands about 10% greater, and on Vaccinium-type stands 15–20% greater than in natural-normal pine stands.

The total volume increment in 70 years old Myrtillus-type stands was 580 m3/ha over bark, and in 80 years old Vaccinium-type stands 520 m3/ha. The total removal on Myrtillus-type sites totalled nearly 350 m3/ha in sown pine stands up to 70 years of age, and 280 m3/ha on Vaccinium-type stands. The total yield in sawn timber per hectare rises up to 6,300 cubic ft in a 70 years old stand on Myrtillus-type stands, and 5,300 cubic ft in Vaccinium-type stands. In conclusion, the volume and increment development of managed pine stands established by sowing up to 70–80 years of age is largely the same as in repeatedly thinned pine stands, but the structure and yield offer greater advantages. The investigation demonstrates that, in the case of Scots pine, sowing is an advantageous method of regeneration. Sowing is an advantage especially in the cases where natural regeneration is uncertain and slow.

The PDF includes a summary in English.

  • Kallio, E-mail: kk@mm.unknown (email)
article id 7110, category Article
Kullervo Kuusela. (1959). Suurin kestävä hakkuusuunnite ja sen metsätaloudellinen merkitys. Acta Forestalia Fennica vol. 71 no. 1 article id 7110. https://doi.org/10.14214/aff.7110
English title: Largest permanent allowable cut and a method for its calculation.
Original keywords: mänty; hakkuusuunnitelma; metsänarviointi; kasvu; hakkuusuunnite; suurin kestävä hakkuusuunnite; kasvuennuste
English keywords: Pinus sylvestris; Scots pine; allowable cut; forest mensuration; increment; largest allowable cut
Abstract | View details | Full text in PDF | Author Info

The purpose of the investigation was to study the factors which determine the amount of the largest permanent allowable cut and to work out a method to estimate it. There is a need to have a ’short cut’ formula for rough preliminary estimates. The preliminary estimates will be checked by stock development forecasts. The largest allowable cut and its sustained basis are only guaranteed by a forecast through a period during which all the present tree stands have reached maturity and exploited.

Estimations of the largest permanent allowable cut are based on the data of the present and desirable growing stock. The present stock was a growing stock of Scots pine (Pinus sylvestris L.) dominated stands on Vaccinium type forests in Southern Finland. The connected Austrian formula is a simple way for preliminary estimation of the largest cut but its sustained basis must be checked by a stock development forecast.

In a stock development forecast the future increment and cut are calculated. For this purpose, the average site quality, tree species, age class and average volume in each class seem to be sufficient variables. The forecast is carried out within the limiting data of the present and desirable stock.

If there is an abundance of mature and over-mature stands, the largest permanent allowable cut is greater than the present increment, provided, however, that bulk of the cut is drawn by determined generation measures. Measured in solid cubic meters, the sustained cut from the Southern Finnish pine stock exceeds the present increment by 11%. With regard to the sustained saw timber production the cut can exceed the present increment by 5–7%.

The PDF includes a summary in English.

  • Kuusela, E-mail: kk@mm.unknown (email)
article id 7486, category Article
Paavo Yli-Vakkuri. (1959). Siemensiipien hankaajista ja niiden vaikutuksesta siemenen itävyyteen. Acta Forestalia Fennica vol. 68 no. 4 article id 7486. https://doi.org/10.14214/aff.7486
English title: On machines for abrading seed wings and their influence on the germinative capacity of the seed.
Original keywords: kuusi; mänty; laitteet; metsäpuiden siemenet; karistamot; siemensiivet; siemensiipien hankaajat
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Socts pine; seeds of forest trees; seed extraction; seed wings
Abstract | View details | Full text in PDF | Author Info

This paper deals with two machines designed for abrading seed wings, and their influence on the germinative capacity of seed of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.). Both machines are commonly used in Finland.

The results of the study indicate that the act of abrading may cause slight or even serious injuries to the seed. Slight injuries of about 3% are probably not easily avoided if mechanical abrading is resorted to. It must be noted, however, that even this reduction in germinative capacity causes significant yearly loss. If the reduction in germinative capacity is greater, which seems to be possible, it is advisable to test the mechanism of the machine and its method of abrading. As the clearance of the machines can affect the extent of injuries, all machines should be tested. If possible, a continual operation control should be arranged. It could, at the same time, to supply material for improving the abrading method and equipment.

The PDF includes a summary in English.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7478, category Article
Paavo Yli-Vakkuri. (1958). Tutkimuksia ojitettujen turvemaiden kulotuksesta. Acta Forestalia Fennica vol. 67 no. 4 article id 7478. https://doi.org/10.14214/aff.7478
English title: Studies on prescribed burning of drained peatlands.
Original keywords: mänty; luontainen uudistaminen; kulotus; suot; pintakasvillisuus; turvemaat; uudistaminen; turvekankaat; vesaikko
English keywords: Pinus sylvestris; regeneration; natural regeneration; drained peatlands; Scots pine; coppice; peatlands; ground vegetation; prescribed burning
Abstract | View details | Full text in PDF | Author Info

Prescribed burning has been used to treat the mineral soil sites, but the method has been little used in drained peatlands. The course and methods of prescribed burning in drained peatlands, and the effect of burning on sprouting of broadleaved trees, growth of ground vegetation and regeneration of Scots pine (Pinus sylvestris L.) by sowing was studied in drained pine bogs in Southern Finland. The top layer of the peat was mostly Sphagnum peat. The material included a prescribed burned 12 ha drained peatland area in Tuomarniemi district, in addition to which ten previously burned areas were investigated.

The burning had succeeded mostly well, but also unsuccessfully burned sites were observed. Estinguishing of the fire was easy, and no peat fires occurred. The fire burned only the logging residue, ground vegetation and the dry top layer of the peat. The roots of brushwood and grasses survived in the peat that insulated the top layer from the heat. For instance, the abundance of cloudberry (Rubus chamaemorus L.) increased after the fire. Similarly, burning did not affect sprouting of the stumps of downy birch (Betula pubescens Ehrh.). It cannot thus be used as a method to restrict the growth of coppice in regenerated areas. The seeds of Scots pine germinated well on the burned surface. 46% of the seeds developed to seedlings on sphagnum-shrub vegetation and 16% in feathermoss-shrub vegetation.

The PDF includes a summary in German.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7476, category Article
Leo Heikurainen. (1958). Sekametsiköiden juuristoista ojitetulla suolla. Acta Forestalia Fennica vol. 67 no. 2 article id 7476. https://doi.org/10.14214/aff.7476
English title: Root systems of mixed forest in drained peatlands.
Original keywords: kuusi; ojitus; mänty; juuristo; koivu; turvekangas; mykorritsa; sekametsikkö
English keywords: Pinus sylvestris; Norway spruce; birch; Picea abies; drained peatlands; Scots pine; peatlands; mixed forests; mycorrhiza; Betula sp.; draining; root system; roots
Abstract | View details | Full text in PDF | Author Info

Draining transforms root systems of trees growing in peatlands towards the ones growing on mineral soil. However, even after efficient draining the root systems differ from the root systems of trees growing on mineral soil. This investigation concentrates on root systems of forests of similar mire types growing in similar draining conditions but having different tree species compositions. The peatland, situated in Pieksämäki in Southern Finland, was drained in 1937. Sample plots, measured in 1956, consisted of mixed forest of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst.) and birch (Betula sp.) in different compositions, and were in natural condition.

The sedge pine bog studied in this investigation was shown to have larger total amount of roots and mycorrhiza than in previously studied dwarf shrub pine bogs. This reflects better growth conditions of the better site. The depth of root system was, however, similar. Root systems of birch were deeper than those of the coniferous tree species. Differences between Scots pine and Norway spruce were small. Corresponding differences between the species were found in the density and total number of mycorrhizas. The abundance of mycorrhizas in the roots of birch increased in deeper layers of peat, but decreased especially in spruce roots. In earlier studies the abundance of mycorrhizas decreased in the roots growing in deeper layers in pure Scots pine stands, but no such variation was seen in this study. The result suggest that the deep root system of birch may affect also the root systems of the coniferous trees. On the other hand, birch roots can have advantage over the coniferous trees.

The PDF includes a summary in German.

  • Heikurainen, E-mail: lh@mm.unknown (email)
article id 7475, category Article
Peitsa Mikola. (1958). Liberation of nitrogen from alder leaf litter. Acta Forestalia Fennica vol. 67 no. 1 article id 7475. https://doi.org/10.14214/aff.7475
Keywords: Pinus sylvestris; Scots pine; seedling growth; seedlings; litter; alder; soil improvement; Alnus sp.
Abstract | View details | Full text in PDF | Author Info

Litters of different plant species vary greatly in regard to their nutrient content and other properties. The aim of the study was to compare different litters from the standpoint of their value as soil fertilizer. In an experiment Scots pine (Pinus sylvestris L.) seedlings were grown in pot cultures in which known amounts of different litters had been mixed with the soil. The tested litters were Pinus sylvestris (L.), Larix sibirica (Ledeb.), Betula sp., Populus tremula (L.), Alnus incana (L.) Moench, A. glutinosa (L.) (Gaertn.), Sorbus aucuparia (L.), Tilia cordata (Mill.), Acer platanoides (L.), Corylus avellana (L.), Eupteris aquilina (L.), and Deschampsia flexuosa (L.) Trin.

A striking difference was found between alder (Alnus sp.) leaf litter and all the other litters tested. The difference can be seen from the second growth season on, becaus the young seedling uses mainly the nutrients included in the seed. The leaf litter has mainly unfavourable effect on the growth of the pine seedlings. Only both alder species improve the growth. This is mainly due to the nitrogen content of alder leaves. Tree leaves and other forest litter are often composted in the forest nurseries. It seems that adding nitrogen to the compost is necessary, otherwise compost added to the soil may have a harmful effect on the seedlings. Alder, on the other hand, has nitrogen binding Actinomyces growing in symbiosis in its root nodules, and is able to utilize atmospheric nitrogen.

The PDF includes a summary in Finnish.

  • Mikola, E-mail: pm@mm.unknown (email)
article id 7472, category Article
Jaakko Lehto. (1956). Tutkimuksia männyn luontaisesta uudistumisesta Etelä-Suomen kangasmailla. Acta Forestalia Fennica vol. 66 no. 2 article id 7472. https://doi.org/10.14214/aff.7472
English title: Studies on the natural regeneration of Scots pine on the upland soils of Southern Finland.
Original keywords: mänty; luontainen uudistaminen; taimettuminen; uudistuminen
English keywords: Pinus sylvestris; regeneration; natural regeneration; Scots pine; stocking with seedlings
Abstract | View details | Full text in PDF | Author Info

Natural regeneration of Scots pine (Pinus sylvestris L.) by leaving a seed tree stand on a cutting area has long been the most popular regeneration method in Finland. Results of the method have, however, been unsatisfactory. The aim of the investigation was to study the basic problems of natural regeneration of Scots pine. Regeneration success was studied in 144 sample plots in pine stands at different stages of regeneration in Southern Finland. In addition, the data included information of 42 previously investigated areas.

According to the results, Scots pine can be successfully regenerated naturally on sandy and gravelly soils in Southern Finland. Preparing the ground surface by breaking or burning considerably facilitates the establishment of a seedling stand. The number of seedlings was considerably lower in the ground vegetation than in the mineral soil. Considering growth of the seedlings, root competition of the mother trees was heavy in dense stands, but insignificant in thin stands. The stand density did not affect germination of the seeds. In regeneration areas proper, where the density of mother trees usually is under 50 per hectare, there was in average 4,700 seedlings per hectare in Calluna type forests and 5,200 in Vaccinium type forests.

The PDF includes a summary in English.

  • Lehto, E-mail: jl@mm.unknown (email)
article id 7466, category Article
Leo Heikurainen. (1955). Rämemännikön juuriston rakenne ja kuivatuksen vaikutus siihen. Acta Forestalia Fennica vol. 65 no. 3 article id 7466. https://doi.org/10.14214/aff.7466
English title: Structure of Scots pine root systems in a pine swamp and effect of draining on the structure.
Original keywords: ojitus; suo; mänty; juuristo; räme; mykorritsa
English keywords: Pinus sylvestris; drained peatlands; Scots pine; peatlands; mycorrhiza; root system; pine swamp; pine pog
Abstract | View details | Full text in PDF | Author Info

The root system of a Scots pine (Pinus sylvestris L.) growing on a peatland is restricted, according to earlier studies, on the top layers of the peat above the groundwater level. Drainage of the peatland affects growth of the root system. This investigation aims at studying the root systems on the point of view of draining of peatlands. The structure and distribution, and the growth of mycorrhiza in Scots pine roots in pine swamps varying from natural state to well drained state is studied.

The study shows that Scots pine on pine swamps has more extensive root system than has earlier assumed, it is common to find 1,000 m of roots in one cubic meter in a healthy stand. The trees reach this density of roots early on. In a drained peatland, the total root length is markedly higher than in a similar stand in natural state. The root systems proved to be very shallow. Even in a well-drained site the roots did not grow deeper than 20 cm. 70% of all roots were found in the upper 5 cm layer of peat, and 90% in the upper 10 cm layer. Root systems were deeper in drained peatlands, but the difference was small. In a site in natural state the average depth of the roots was 4 cm, and in a drained site 5 cm. About 85% of the roots were under 1 mm of diameter. Short roots were found only in the fine roots. Draining increases strongly the number of short roots. Mycorrhizas of the types A, B, C and D as well as pseudomychorrizas were found in the pine roots.

The PDF includes a summary in German.

  • Heikurainen, E-mail: lh@mm.unknown (email)
article id 7440, category Article
Erkki K. Kalela. (1954). Mäntysiemenpuiden ja -puustojen juurisuhteista. Acta Forestalia Fennica vol. 61 no. 28 article id 7440. https://doi.org/10.14214/aff.7440
English title: Root systems of Scots pine seed trees and stands.
Original keywords: mänty; taimettuminen; juuristo; uudistuminen; siemenpuut; juurikilpailu
English keywords: Pinus sylvestris; regeneration; natural regeneration; Scots pine; seedlings; seed trees; root system; root competition
Abstract | View details | Full text in PDF | Author Info

Root systems of a Scots pine (Pinus sylvestris L.) stands of seed trees on a Vaccinium sites in Southern Finland were studied by taking soil samples around the seed trees. The results show that root system of an old Scots pine spreads relatively evenly around the tree up to at least 10 meters from the stem. The densest part of the root system is near the stem, which part is often acentric. This is probably due to root competition in the early stages of growth of the tree.

Root systems of the seed trees affect stocking of the site with seedlings and the growth of the seedlings. The root competition can cause, for instance, uneven grouping of the seedlings. It seems that the largest trees of a stand have the most even root system. It is therefore recommended to choose the strongest trees of the stand as seed trees, to ensure even distribution of seedlings.

The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.

The PDF includes a summary in German.

  • Kalela, E-mail: ek@mm.unknown (email)
article id 7439, category Article
Leo Heikurainen. (1954). Rämemänniköiden uudistamisesta paljaaksihakkausta käyttäen. Acta Forestalia Fennica vol. 61 no. 27 article id 7439. https://doi.org/10.14214/aff.7439
English title: Regeneration of Scots pine stands of pine swamps through clear cutting.
Original keywords: männikkö; luontainen uudistuminen; mänty; suot; alikasvos; uudistaminen; räme; turvekangas; avohakkuu
English keywords: Pinus sylvestris; regeneration; natural regeneration; drained peatlands; Scots pine; peatlands; seedlings; fellings; undergrowth; pine swamps; clear cutting
Abstract | View details | Full text in PDF | Author Info

Pine swamps are easily regenerated by natural regeneration of Scots pine (Pinus sylvestris L.). Usually seeding felling is used, but also strip system or clear cutting and regeneration along stand edge has been suggested. This article discusses the regeneration by clear cutting and sparing the existing undergrowth. The article focuses on pine swamps to be drained and the ones in natural state.

Pine swamps in natural state usually have plenty of trees of smaller diameter classes, that can be trusted to form the future tree generation after the felling. This shortens the rotation by 20-30 years. The undergrowth has been shown to recover quickly. The method suits for regeneration of drained peatlands but could fit also for regeneration of pine swamps in natural state.

The seedlings in the pine swamps are mainly 1-5 years old, and the stock is changing. It seems that larger trees produce a wider selection of age groups, but the seedlings survive longer under smaller mother trees. Part of the younger generations of seedlings seem to be destroyed when the peatland is drained. Further studies are needed to investigate how the draining and felling are to be performed to spare the young seedlings.

The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.

The PDF includes a summary in German.

  • Heikurainen, E-mail: lh@mm.unknown (email)
article id 7432, category Article
Ukko Rummukainen. (1954). Männyn ja kuusen käpysadosta ja sen arvioinnista vuosina 1950-1953. Acta Forestalia Fennica vol. 61 no. 20 article id 7432. https://doi.org/10.14214/aff.7432
English title: Estimation of Scots pine and Norway spruce cone crop in 1950-1953.
Original keywords: kuusi; mänty; käpysato; siemenkeräys; käpykeräys; arviointimenetelmä
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; seed collection; cone crop; cone collection; assessment method
Abstract | View details | Full text in PDF | Author Info

The cone crop of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) has been assessed in Finland since 1930 annually by sending a questionnaire to forest professionals around the country. Based on the result it is decided if the crop is good enough for collection of the cones next winter. This article presents the results of cone surveys in 1950-1953, and suggest improvements in the method of the investigation.

According to the survey, Scots pine crop was best in 1952, when the crop was intermediate in the whole country, and relatively abundant in the county of Lapland. Norway spruce crop was best in 1951, when the crop was better than in average in the whole country. The evaluators had variable opinions whether the crop was good enough for cone collection or not. They assessed the pine cone collection more often as profitable than the spruce cone collection. Usual reasons to regard spruce cone collection as unprofitable were seed damages and the sites being too far away. To make the results more uniform and accurate, a suggestion to change the evaluation method is presented. The evaluation should be focused on the cone crop of mature stands.

The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.
The PDF includes a summary in German.

  • Rummukainen, E-mail: ur@mm.unknown (email)
article id 7411, category Article
Aarne Nyyssönen. (1954). Hakkauksilla käsiteltyjen männiköiden rakenteesta ja kehityksestä. Acta Forestalia Fennica vol. 60 no. 4 article id 7411. https://doi.org/10.14214/aff.7411
English title: Structure and development of Scots pine stands treated with different cuttings.
Original keywords: hakkuut; mänty; kasvatushakkuu; harvennushakkuu; rakenne; tuotto; harsinta; harsintahakkuu
English keywords: Pinus sylvestris; yield; Scots pine; thinnings; fellings; selection cuttings; intermediate thinning
Abstract | View details | Full text in PDF | Author Info

Permanent sample plots are considered to be the most reliable basis for investigations into structure and development of stands. Such sample plots, established since 1924 in Finland, have been used to study thinnings of varying intensity. These studies are yet too short to give comprehensive conclusions. It is also possible to base the studies on sample plots measured in managed forests and gain in this way information suitable for practical purposes. In this investigation development of stands treated by two different methods, repeated thinnings and repeated selection cutting were studied in pure, even-aged Scots pine (Pinus sylvestris L.) stands in Southern Finland, on three forest types.

The results show that volume increment level of naturally normal stands seem to have been reached easily by stands treated with repeated thinnings. With advancing age, the growing stock of thinned stands fall short from the natural stands. As thinnings have removed primarily the poorest trees, the increment is distributed over trees of a larger size more in thinned than in naturally normal stands.

When intensive cuttings have resulted in a relatively small growing stock, the decrease in volume increment leads to considerable decrease in volume. The size of the tree has no essential effect – within certain limits - on the volume increment of the stand, if the volume removed is similar. However, every intermediate thinning removing largest-sized trees may result in the prolonged rotation. Since the volume increment of an older stand is much smaller than earlier, intermediate thinnings removing largest-sized trees should be avoided if the aim is the greatest volume yield. The growing stock of middle-aged or older stands untreated or treated with slight cuttings only can as a rule be considerably reduced without volume increment declining.

The PDF includes a summary in English.

  • Nyyssönen, E-mail: an@mm.unknown (email)
article id 7410, category Article
Paavo Yli-Vakkuri. (1953). Tutkimuksia puiden välisistä elimellisistä juuriyhteyksistä männiköissä. Acta Forestalia Fennica vol. 60 no. 3 article id 7410. https://doi.org/10.14214/aff.7410
English title: Studies on physical root connections between the trees in Scots pine stands in Finland.
Original keywords: mänty; juuristo; juuriyhteys; elävä kanto
English keywords: Pinus sylvestris; Scots pine; root system; root connection; living stump
Abstract | View details | Full text in PDF | Author Info

Observations of connections between the roots of living trees and root systems of stumps have been reported already in 1900s. In Finland root connections have been found in Birch (Betula sp.), Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.), but there are no studies on abundance of the connections. This investigation studied root connections in a series of naturally regenerated Scots pine stands from seedling stands to mature trees in Southern Finland, and some sown seedling stands.

Root connections were found to be common in naturally regenerated, older stands that had passed the thicket stage. Approximately 21-28% of the trees had at least one root connection to another living tree, dead tree or living stump. Connections were few or absent in seedling stands. Sown seedling groups had many root connections in contrary to naturally regenerated seedling stands. Trees belonging to the dominating canopy class had most root connections. The trees could form a network of up to twenty trees and living stumps. Root connections were more common the larger the tree was or the nearer the trees grew each other. The coalescent roots were often situated near the stem. Experiments showed that water and nutrients transferred in the roots could move from one tree to another. Living stumps from previous fellings were relatively common. In the sites studied, there was in average 178 stumps connected to a living tree per hectare.

The PDF includes a summary in German.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7407, category Article
Olli Vaartaja. (1951). Alikasvosasemasta vapautettujen männyn taimistojen toipumisesta ja merkityksestä metsänhoidossa. Acta Forestalia Fennica vol. 59 no. 3 article id 7407. https://doi.org/10.14214/aff.7407
English title: On the recovery of released Scots pine undergrowth and its silvicultural importance.
Original keywords: mänty; alikasvos; taimikko; kasvu; laatu; ylispuuhakkuu; ylispuut
English keywords: Pinus sylvestris; Scots pine; seedlings; undergrowth; hold-overs; removal of hold-overs; felling of standards
Abstract | View details | Full text in PDF | Author Info

There are contrary opinions on the ability of Scots pine (Pinus sylvestris L.) seedlings to withstand oppression by hold-overs and recover after their felling. The recovery potential of oppressed pine stands in Southern and Northern Finland was studied using two kinds of material, fully recovered Scots pine stands and stands recently released. The volume and volume increment of the stand were measured, and the health of the sample trees was determined.

The study showed that those released pine stands that had been in oppressed state very long (25-60 years) had recovered after clear-cutting. After the release the stands grew at first slowly, but after recovery at about the same rate as natural normal stands of a similar height. The smaller, younger, and less stunted the seedlings were when they were released, and the better the site, the faster was the recovery. At the base of released pine stands various defects was detected. When the trees were released, the defects decrease their technical value. A heavy partial cutting had generally a disadvantageous effect on the stand. Recovering seedlings were found clearly to hinder the development of younger seedlings nearby. This inhibition seemed to be a result of the rapid spread of the root system of released pine trees.

The PDF includes a summary in English.

  • Vaartaja, E-mail: ov@mm.unknown (email)
article id 7406, category Article
Jaakko O. Murto. (1951). Mäntypuumme pihka voiteluöljyn raaka-aineena : puunkäyttöopillinen tutkimus. Acta Forestalia Fennica vol. 59 no. 2 article id 7406. https://doi.org/10.14214/aff.7406
English title: Finnish Scots pine resin as raw material for lubricating oil.
Original keywords: mänty; sota-aika; kannot; pihka; voiteluöljy; pihkaöljy; männynpihka; mäntyöljy; sulffaattiselluloosa
English keywords: Pinus sylvestris; Scots pine; resin; lubricating oil; war-time; tall oil; tar wood; sulphate pulp mill
Abstract | View details | Full text in PDF | Author Info

After the Second World War shortage of lubrication oil forced Finland to develop a substitute product that was produced of indigenous materials. This report is an overview of the history of the already terminated lubricating oil industry and it gives a detailed description of lubricating oil production.

The annual lubricating oil consumption in Finland was 15,000 tons before the war, but during the war it decreased to 7-8,000 tons. In 1943 Oy Tervaöljy Ab (Tar Oil Limited) was established with the state of Finland as the main shareholder. It was commissioned to plan and build tar and tar oil plants, and it also transmitted tar from stump wood pyrolyzing plants to oil factories. Two raw materials were used to produce tar oil: tar wood collected from Scots pine (Pinus sylvestris L.) stumps and tall oil, a by-product of sulphate pulp mills. A total of 9,000 tons of lubricating oil substitutes was produced in 1943-1947, 53% of this from sulphate pulp mill by-products and 47% from tar and shale oil.

The PDF includes a summary in English.

  • Murto, E-mail: jm@mm.unknown (email)
article id 7398, category Article
Erkki K. Kalela. (1949). Männiköiden ja kuusikoiden juurisuhteista I. Acta Forestalia Fennica vol. 57 no. 2 article id 7398. https://doi.org/10.14214/aff.7398
English title: On the horizontal roots in Scots pine and Norway spruce stands.
Original keywords: kuusi; mänty; juuristo; juurikilpailu; juuriston kasvu
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; competition; root system; roots; root competition; growth of roots
Abstract | View details | Full text in PDF | Author Info

The purpose of the investigation was to study the amount, quality and distribution by layers of depth of horizontal roots in Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) stands in Southern Finland. The sample plots included stands on soil varying from sandy to stony, and stands of  varying ages from seedling stands to an old stand, in Myrtillus and Vaccinium type forests.

In a Norway spruce stand, the amount of roots increases rapidly and reaches its maximum, about 450 meters/m3, at an age of 100-110 years. In a Scots pine stand the maximum, about 370 m/m3, is reached earlier, at an age of 60-70 years. The root system of pine expands more rapidly than that of spruce. The total length of the horizontal root system of pine amounts to 1,000 m soon after 40 years of growth, of spruce at the age of 60. Later the situation changes, and at the age of 110 the root systems of both species are about the same size, but older trees of spruce have more extensive root system.

Majority of horizontal roots are under 1 mm in diameter. Of the horizontal roots of spruce stands the majority lie in the humus layer and in the topmost mineral soil stratum. Over half of horizontal spruce roots are, thus, at a maximum depth of 5 cm, while majority of the roots of Scots pine lie at maximum in depth of 10 cm. At the same layer grow also the roots of the ground vegetation, which may affect the competition between the species.

The PDF includes a summary in English.

  • Kalela, E-mail: ek@mm.unknown (email)
article id 7381, category Article
Erkki K. Kalela. (1946). Pihkomiskokeita pohjoisissa männiköissä. Acta Forestalia Fennica vol. 52 no. 3 article id 7381. https://doi.org/10.14214/aff.7381
English title: Collection of resin in Scots pine forests in the Nordic countries.
Original keywords: mänty; pihka; pihkan keräys; pihkominen
English keywords: Pinus sylvestris; Scots pine; pitch; resin; resin collection
Abstract | View details | Full text in PDF | Author Info

Systematic resin collection has not been practiced in Finland or other Nordic areas. One reason is the short growing season. Also, the local pine species, Scots pine (Pinus sylvestris L.) gives smaller resin yield than the southern species, such as Pinus maritima. In Nordic boreal forests resin has been collected only in the Soviet Union, where it has been practised also in Eastern Karelia, near the Finnish border. Resin collection experiments were arranged in former resin collection stands in Karelia in 1943. A so-called German method for running resin had been used in the stands. 30-40 sample trees were chosen in five sample sites.

Forest type did not have big influence in the resin yield. The yield seemed to be slightly higher in Scots pine stands growing in fertile sites compared to poorer sites. The diameter of the tree had largest effect on the yield. It is recommended to focus on stands with large trees, and trees with a large, vital crown. In this kind of stands it is possible to get best yield in relation to the work required. The height of the patch that was cut in the stem had no influence on the yield. The size of the patch should, however, not exceed 35-50% of the diameter of the tree.

The PDF includes a summary in German.

  • Kalela, E-mail: ek@mm.unknown (email)
article id 7367, category Article
Esko Kangas. (1942). Karistuslämmön vaikutuksesta männyn siemenen karisemiseen ja itämiseen. Acta Forestalia Fennica vol. 50 no. 14 article id 7367. https://doi.org/10.14214/aff.7367
English title: Effect of seed extracting temperature on extraction and germination of Scots pine seeds.
Original keywords: mänty; siementuotanto; itäminen; siemenet; karistus; karistuslämpötila
English keywords: Pinus sylvestris; germination; Scots pine; temperature; seeds; seed production; seed extraction
Abstract | View details | Full text in PDF | Author Info

Temperatures needed in extracting Scots pine (Pinus sylvestris L.) seeds is relatively high, however, there is little information on its effect on germination of the seeds. This survey aimed at studying how different temperatures affect both extraction result and germination of Scots pine seeds. Comparisons between different temperatures (20, 30, 40, 50, 60 and 70 ºC) were made from cones collected from same sample trees, three trees in total.

Temperatures 20 and 30 ºC resulted in incomplete opening of the cones, and gave thus smaller amount of seeds. Complete extraction requires at the least the temperature of 40 ºC. The result is slightly better in 50 ºC, but germination of the seeds is little lower. Temperatures 60 and 70 ºC improve the results, but in the cost of germination. The main reason for lower germination percentage was that the higher temperatures release more empty and defective seeds from the cones. Results of different sample trees were different due to, for instance, quality and size of cones. Higher temperatures accelerated the extraction. According to the study, perfect extraction in 40 ºC requires longer extraction time than when the temperature of 50 ºC is used. In practice, 50 ºC temperature or even little higher temperatures can be used when the extraction time is shorter. Decessive factors in choosing the temperature would be the humidity of cones and length of extraction time.

The PDF includes a summary in German.

  • Kangas, E-mail: ek@mm.unknown (email)
article id 7361, category Article
M. Lappi-Seppälä. (1942). Siperian lehtikuusen kasvusta sekametsiköissä Evon valtionpuistossa. Acta Forestalia Fennica vol. 50 no. 8 article id 7361. https://doi.org/10.14214/aff.7361
English title: Growth of Siberian larch in mixed stands in state forests of Evo in Finland.
Original keywords: kuusi; tiheys; mänty; sekametsä; siperianlehtikuusi
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; growth; mixed forests; Siberian larch; Larix sibirica
Abstract | View details | Full text in PDF | Author Info

Of the foreign tree species Siberian larch (Larix sibirica Ledeb.) has the biggest economical potential in Finland. In its natural distribution the species grows mostly in mixed stands in other areas than the core of its range in Siberia, where it grows also in pure stands. However, growth studies have given contradictory results about how Siberian larch can manage competition of different tree species in mixed stands. In this study two-year old Siberian larch seedlings were planted in areas previously sown with Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). The growth of the trees was measured when the stands were 50 years old.

It appears that the stands, about 3700 larch seedlings per hectare, have originally been too been too dense. In the two thinnings done in the area, larch has probably been favoured, which has resulted in varying mix of pine and spruce. In the 50-year old stands, Siberian larch has developed faster than Scots pine and Norway spruce. Contrary to some previous studies, the results show that Siberian larch can be grown also in mixed stands, but the growth will probably be slower than in pure stands. Best growth is achieved in pure stands that have been planted thinly enough.

The PDF includes a summary in German.

  • Lappi-Seppälä, E-mail: ml@mm.unknown (email)
article id 7359, category Article
V. T. Aaltonen. (1942). Muutamia kasvukokeita puuntaimilla. Acta Forestalia Fennica vol. 50 no. 6 article id 7359. https://doi.org/10.14214/aff.7359
English title: Growth studies on tree seedlings.
Original keywords: kuusi; mänty; taimikasvatus; koivu; kilpailu; itäminen; kasvututkimukset
English keywords: Pinus sylvestris; Norway spruce; birch; Picea abies; Scots pine; competition; Betula sp.; growth studies; germinatio
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to investigate effect of growth conditions on germination and growth of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings in greenhouse conditions. Germination of seeds becomes markedly slower as the soil temperature decreases. It seems that low temperatures affect more Norway spruce than Scots pine. When temperature rises, the fresh weight of the seedlings increases more in pine seedlings than in spruce seedlings. Accordingly, lower temperatures affect less the weight growth of spruce seedling than that of pine seedlings.

An experiment testing how root competition affect germination showed that adjacent seedlings decrease germination of seeds more than shading with branches. The effect was strongest on pine and spruce seedlings when the shading tree species was fast growing birch (Betula sp.). On the other hand, shading affected most height growth of birch seedlings. Growing space can vary in relatively large range without it affecting greatly tree growth.

The PDF includes a summary in German.

  • Aaltonen, E-mail: va@mm.unknown (email)
article id 7354, category Article
P. S. Tikka. (1940). Puiden vikanaisuuksien merkitys ja huomioon ottaminen Perä-Pohjolan mäntymetsien hoidossa. Acta Forestalia Fennica vol. 50 no. 1 article id 7354. https://doi.org/10.14214/aff.7354
English title: The effect of injuries in trees on forest management of Scots pine stands in Northern Finland.
Original keywords: Pohjois-Suomi; metsänhoito; mänty; sienitaudit; vikaisuus; latvuskerrokset; tervasroso
English keywords: Pinus sylvestris; forest management; Scots pine; Cronartium flaccidum; pathogens; crown class; injuries; diseases; Scots pine blister rust
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to find out what are the causes of damage in Scots pine (Pinus sylvestris L.) stands and the frequency of different kinds of injuries, which are then discussed in relation to the silvicultural state and management of the stands in comparison to ideal forests. Sample plots were studied in over 80-year old Scots pine dominated stands in mineral soil sites of different forest types in Northern Finland in the area of Perä-Pohjola. 10–40 trees were chosen as sample trees in each sample plot. The sample trees were felled, and the diameter, height of crown and injuries outside and inside of the stem were recorded.

Length of knot-free part of the stem was higher in the dominant trees and in older age classes of the trees. The form of the stem becomes broader and rounder with the age. The crowns are, however, longer in Northern Finland compared to Southern Finland. In management of Scots pine stands, all trees diseased by Scots pine blister rust (Cronartium flaccidum) should be removed. The disease is common in Northern Finland, and the number of diseased trees increases as the stands get older. Decay was more common in trees that had fire wounds. In general, injuries decreased the length and diameter growth of the trees. From the dominant trees should only injured and diseased trees removed in the thinnigs. Codominant trees can be left to grow when spare trees are needed to replace missing dominant trees. Detailed instruction of selection of the removed trees are given for each age class.

The PDF includes a summary in German.

  • Tikka, E-mail: pt@mm.unknown (email)
article id 7351, category Article
Esko Kangas. (1940). Tuloksia Pohjankankaan ja Hämeenkankaan metsänviljelyksistä. Acta Forestalia Fennica vol. 49 no. 4 article id 7351. https://doi.org/10.14214/aff.7351
English title: Studies on artificial regeneration in Pohjankangas and Hämeenkangas in Southern Finland.
Original keywords: kylvö; mänty; metsäpalo; metsänuudistaminen; taimikko; kulo; hyönteistuho; sienituho
English keywords: Pinus sylvestris; regeneration; Scots pine; seedling damage; ; seedling stands; insect damage
Abstract | View details | Full text in PDF | Author Info

The regeneration of forests in Hämeenkangas area in Southern Finland has been difficult due to various damages from the middle of the 1800s. Few seed trees were left in the area, and artificial regeneration has been used since 1880s. The area became an experimental area of the Forest Research Institute in 1924. The aim of the study was to survey the area before it was transferred to the Finnish Defense Forces.

The original Scots pine (Pinus sylvestris L.) forest of the esker area suffered from many forest fires. The total area is 13,000-14,000 ha, of which the experimental forests of Forest Research Institute cover 6,000 ha. The area is dry upland forest, and drought affects the survival of germlings. Soil frost is a major cause of loss of young seedlings. Sowing method affects the early development of the seedlings. Band sowing proved to be the best method regarding the soil frost. A total of 39 different harmful insect species, 8 pathogen species and 7 other causes of damages have been detected in the area.

The development of seedling stands follow a certain pattern, reported also in other studies. Many of the pine seedling stands develop well until they reach a certain height. After that seedlings begin to suffer from damages, but after reaching another stage develop normally. The damages affect the height growth of the seedlings. Some common damages are caused by Pissoides weevils, needle damages caused by certain beetles, shoot damages by Evetria resinella, and pine blister rust (Peridermium pini and Cronartium flaccidum).

The PDF includes a summary in German
  • Kangas, E-mail: ek@mm.unknown (email)
article id 7336, category Article
R. Sarvas. (1937). Kuloalojen luontaisesta metsittymisestä : Pohjois-Suomen kuivilla kankailla suoritettu metsäbiologinen tutkielma. Acta Forestalia Fennica vol. 46 no. 1 article id 7336. https://doi.org/10.14214/aff.7336
English title: Natural regeneration of burned areas. Forest biological study in dry mineral soil sites in Northern Finland.
Original keywords: luontainen uudistuminen; Pinus sylvestris; metsäpalo; Betula sp.; taimikonhoito
English keywords: Norway spruce; birch; Picea abies; forest fire; Socts pine; tending of seedling stands
Abstract | View details | Full text in PDF | Author Info

Natural regeneration has been common in Northern Finland, where forest fires have been usual, and the large areas make artificial regeneration expensive. The regeneration, and for instance tree species composition and density of the stand, cannot been controlled. In Northern Finland there is little demand for Betula sp. which is often abundant in the burnt areas. The unburned forests are generally Scots pine (Pinus sylvestris L.) or Norway spruce (Picea abies (L.) H. Karst.) dominated mixed forests with single Betula sp. trees.

The fire destroys birch for the most part in the Vaccinium site type, but the surviving trees produce enough seeds to regenerate the areas. The largest trees of Scots pine usually survive the fires. Pine has good seed years in the north only every 8th or 10th year. Spruce is totally destroyed in the forest fire and the seedlings grow poorly as primary species. The seedling stands are usually dominated by Scots pine and birch, but birch seedlings grow in batches, and do not hinder growth of pine. The drier Calluna site type stands are dominated by Scots pine. Birch seedlings may be abundant in the beginning, but most of them do not survive. Abundant emergent pine trees prevent the growth of seedlings especially in the dry site types, and they should be thinned to guarantee regeneration. Sowing results are better few years after the fire. The birch seedling should be removed from the seedling stands.

The PDF includes a summary in German.

  • Sarvas, E-mail: rs@mm.unknown (email)
article id 7325, category Article
V. T. Aaltonen. (1936). Kuusi männyn kilpailijana kasvupaikasta. Acta Forestalia Fennica vol. 42 no. 8 article id 7325. https://doi.org/10.14214/aff.7325
English title: Norway spruce as competitor in the sites typical for Scots pine.
Original keywords: Picea abies; Pinus sylvestris; levinneisyys; puulaji; lajien välinen kilpailu
English keywords: distribution; competition between species
Abstract | View details | Full text in PDF | Author Info

Norway spruce (Picea abies (L.) H. Karst.) is a species that becomes in Finland over time the dominant species in the sites that are suitable for it. The reason that it covers only a quarter of the forest areas in Finland depends mainly on forest fires. The aim of this review was to discuss the biological factors that affect competition between Scots pine and Norway spruce.

Especially important is the ability to regenerate and grow past seedling stage. There does not seem to be significant differences in the number of good seed and seedling years of the species. Spruce regenerates better on moss covered forest floor than pine. On the other hand, pine seedlings grow faster than spruce seedlings, and tolerate better dry conditions. Consequently, one of the defining biological differences is that Norway spruce needs more humid conditions than Scots pine. Spruce is shown to have greater transpiration than pine. Spruce also has higher site requirements, however, growing as undergrowth, it seems to be better able to compete of the nutrients with the larger trees than pine. It also tolerates shading better. Spruce is less frost tolerant than pine.

The PDF includes a summary in German.

  • Aaltonen, E-mail: va@mm.unknown (email)
article id 7313, category Article
Erkki Laitakari. (1934). Männyn kääpiöversojen ja kasvainten välisistä suhteista. Acta Forestalia Fennica vol. 40 no. 36 article id 7313. https://doi.org/10.14214/aff.7313
English title: The relations between main and short shoots of Scots pine.
Original keywords: mänty; Pinus sylvestris; neulanen; kääpiöverso
English keywords: needle; short shoot
Abstract | View details | Full text in PDF | Author Info

The number of short shoots and the quality of the shoots and needles in 19 shoots of 15 Scots pine (Pinus sylvestris L.) was measured. Usually Scots pine short shoots have two needles. Three-needle short shoots were found in all sample shoots but one. They were most common in fast-growing trees and the shoots in the main stem. One-needle short shoots were relatively rare. In most cases the second needle had withered. The length of the needles was 19‒80 mm, and most common lengths were 30‒50 mm. The width of the needles was in average 0.5‒1.94 mm. There was correlation between the length of the shoot and the length of the needles.

The PDF includes a summary in German.

  • Laitakari, E-mail: el@mm.unknown (email)
article id 7297, category Article
A. L. Backman. (1934). Om den Åländska skogens förhistoria. Acta Forestalia Fennica vol. 40 no. 20 article id 7297. https://doi.org/10.14214/aff.7297
English title: Early history of forests in Åland, Finland.
Keywords: Pinus sylvestris; Betula; Picea abies; Finland; tree species; distribution; Alnus incana; occurrence; Åland; pollen analysis; paleobotany; Carpinus betulus
Abstract | View details | Full text in PDF | Author Info

The paper presents preliminary results of paleobotanical studies on vegetation in Åland, south-west Finland. The investigations concentrated on studying arrival of tree species and stratigraphy of peatlands. According to the studies, some plant fossils found in the peat (Ceratophyllum submersum, Sparagnium neglectum, Najas flexilis) indicate that climate of the region has earlier been warmer than at the present. The present forests in Åland are dominated by coniferous species, but the pollen analysis of the peat indicate that Norway spruce (Picea abies (L.) H. Karst.) became a common species in the region about by the time of Christ’s birth. The species has reached its present distribution in Åland relatively late. The pollen analyses give relatively little information about the arrival of birch (Betula sp.) and Scots pine (Pinus sylvestris L.), but it seems obvious that occurrence of birch reached its culmination just before spruce. During the warm period common alder (Alnus glutinosa (L.) Gaertn.) was the most important species, and also pollen of oak (Quercus robur L.), kinden (Tilia cordata L.) and elm (Ulmus sp.) was relatively common in the peat of some of the studied peatlands. An interesting finding was the pollen of Carpinus betulus in many sites in Åland.

The PDF includes a Finnish and German summary.

  • Backman, E-mail: ab@mm.unknown (email)
article id 7287, category Article
Erkki K. Cajander. (1934). Havaintoja eräällä myrskytuhoalueella. Acta Forestalia Fennica vol. 40 no. 10 article id 7287. https://doi.org/10.14214/aff.7287
English title: Observations in a storm damage area.
Original keywords: kuusi; Picea abies; mänty; Pinus sylvestris; koivu; Betula sp.; myrskytuho; tuulituho
English keywords: Norway spruce; birch; Scots pine; storm damage; wind damage
Abstract | View details | Full text in PDF | Author Info

A big storm hit Finland in 12.10.1933, and caused forest damages especially in the coasts of the Gulf of Finland and Baltic Sea, and in the eastern part of the country. In these areas the wind felled about 75,000‒85,000 m3 timber trees in the state lands. The extent of the wind damage was measured in forest area of 1,500 hectares in Lapinjärvi in Southern Finland. The wind had felled 42% of the Scots pine (Pinus sylvestris L.), 70% of the Norway spruce (Picea abies (L.) H. Karst.) and 44% of the Betula sp. trees. Thus, Norway spruce had been most susceptible for wind damage. That extensive damages in Norway spruce seed tree stands risk the regeneration in the area. Natural regeneration of Norway spruce using seed trees may, therefore, be questioned. The seed tree areas on hills, and especially hollows next to the hills were susceptible for wind damage. A denser border stand protects sparsely stocked seed tree area. The damages were also smaller in older seed tree areas, where the trees and ground vegetation had had time to recover after the felling. The felled spruce and birch trees had often stem rot.

The PDF includes a summary in German.

  • Cajander, E-mail: ec@mm.unknown (email)
article id 7286, category Article
Matti Jalava. (1934). Havaintoja puun aseman vaikutuksesta puun ominaisuuksiin. Acta Forestalia Fennica vol. 40 no. 9 article id 7286. https://doi.org/10.14214/aff.7286
English title: Influence of the position of a tree in the stand upon the properties of the wood.
Original keywords: mänty; puun laatu; harvennushakkuu; puuaine; lujuus; latvus; kesäpuu; puun mekaaniset ominaisuudet
English keywords: Pinus sylvestris; thinning; Scots pine; crown; properties of wood; strength of wood; summerwood
Abstract | View details | Full text in PDF | Author Info

The growth of a tree is influenced by inherited properties and external circumstances, including climate, soil, the position of the tree in the stand, and the position of the wood in the stem. The tree species have optimum climate and optimum conditions. The aim of this study was to determine if the summerwood content of the wood of Scots pine (Pinus sylvestris L.) is dependent on the rate of growth of the tree. Comparing the position of the sample trees in the stand, it seems that the position of the tree and the size of its crown influences strongly the quality of the wood. In a dense stand the summerwood content was higher in the trees that had small crowns. Thinning of the stand decreased the difference in summerwood content of the trees.

The PDF includes a summary in English.

  • Jalava, E-mail: mj@mm.unknown (email)
article id 7273, category Article
T. J. Hintikka. (1933). Muutamia havaintoja männyn tuulenpesistä. Acta Forestalia Fennica vol. 39 no. 2 article id 7273. https://doi.org/10.14214/aff.7273
English title: Observations on witches' brooms in Scots pine.
Original keywords: mänty; Pinus sylvestris; tuulenpesä; mutaatio
English keywords: mutation; witches' broom
Abstract | View details | Full text in PDF | Author Info

Witches' brooms of Scots pine (Pinus sylvestris L.) have been suggested to be genetic rather than caused by bacteria. Seeds were collected from cones growing in Scots pine witches' brooms. More than half (43) of the 84 seedlings grown from the seeds were stunted and resembled witches' broom. The growth of the normal and witches' broom like seedlings were compared. When the seedlings were 8 years old, the normal seedlings were in average 37 cm and the witches' broom like seedlings 8 cm high. The result supports the theory that the witches' broom like growth was inherited in the Scots pine seedlings.

The PDF includes a summary in German.

  • Hintikka, E-mail: th@mm.unknown (email)
article id 7259, category Article
I. Lassila. (1929). Metsätyypin vaikutuksesta puun painoon. Acta Forestalia Fennica vol. 36 no. 1 article id 7259. https://doi.org/10.14214/aff.7259
English title: The influence of forest site type on the weight of wood.
Original keywords: mänty; Pinus sylvestris; metsätyyppi; puuaineen paino
English keywords: Scots pine; wood; basic density; weight of wood
Abstract | View details | Full text in PDF | Author Info

Earlier research has presented contradictory results of the influence of forest site type on the weight of wood. In this study, dominant trees of Scots pine (Pinus sylvestris L.) was chosen as sample trees on four forest site types: Calluna, Vaccinium, Myrtillus and Oxalis site types. The trees were felled in autumn, when the water content of the wood is low. Weight of the test samples was measured weigh before and after drying. Undried wood, both sapwood and heartwood, is heavier in Myrtillus type than in Vaccinium type. The weight of the air-dried heartwood did not differ between the two forest site types. Air-dried- sapwood was heaviest in Myrtillus site type. Air-dried heartwood was heaviest in Vaccinium site type, and lightest in Oxalis type. Owen-dried sapwood was heaviest in Calluna site type, where the tree growth is slow, but weight differences were small in owen-dried heartwood. It can be claimed that forest type affects wood quality.

The PDF includes a summary in English.

  • Lassila, E-mail: il@mm.unknown (email)
article id 7231, category Article
Martti Hertz. (1929). Huomioita männyn ja kuusen pituuskehityksen "vuotuisesta" ja vuorokautisesta jaksosta. Acta Forestalia Fennica vol. 34 no. 18 article id 7231. https://doi.org/10.14214/aff.7231
English title: Observations on annual and daily cycles in the height growth of Scots pine and Norway spruce.
Original keywords: kuusi; mänty; taimet; lämpötila; pituuskasvu; kasvukausi; vuotuinen vaihtelu
English keywords: Pinus sylvestris; Picea abies; height growth; temperature; seedlings; growing seasons
Abstract | View details | Full text in PDF | Author Info

The height growth of Scots pine (Pinus sylvestris L.) seedlings were observed in Korkeakoski and Evo in Southern Finland in 1925-1928. The growth was slow in the beginning of the growing season, increased after that to decrease again towards the end of the growing season. The height growth begun in May, reached the fastest growth rates in June, and ended in June-July. According to the earlier studies, the length of the height growth of Scots pine is dependent on the temperature of the previous summer. This study showed that warm temperatures of the same summer promote height growth, and low temperatures slow it down. Also the daily growth fluctuates, being highest during the afternoon and slowest during the early morning. The daily growth is dependent on temperature.

Norway spruce (Picea abies (L.) H. Karst.) begin the height growth in average 9 days later than Scots pine. Compared to pine, the speed of growth in spruce decreases slower towards the late summer.

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander. The PDF includes a summary in German.

  • Hertz, E-mail: mh@mm.unknown (email)
article id 7219, category Article
W. E. A. Hiley. (1929). A financial analysis of a money yield table. Acta Forestalia Fennica vol. 34 no. 6 article id 7219. https://doi.org/10.14214/aff.7219
Keywords: Pinus sylvestris; Scots pine; rotation
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to compare the theories of Soil Rental and Forest Rental. There is a controversy between the theories that is associated to the issues of length of rotation and grade of thinning. For the basis of the analysis was chosen Schwappach’s money yield table for Scots pine (Pinus sylvestris L.) Quality II, published in 1908. Based on the table was calculated the financial yield, the net annual income from a normal forest managed on various rotations, the capital value, and the net income expressed as the rate of interest on the capital value. According to the study, it is the rotation at which any money invested in lengthening the rotation still further, would yield no return. In the case of Scots pine, the highest income is achieved approximately with a rotation of 140 years, and the income per hectares would decrease if longer rotations were used, though the capital invested would increase.

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.

  • Hiley, E-mail: wh@mm.unknown (email)
article id 7210, category Article
Erkki Laitakari. (1927). Männyn juuristo: morfologinen tutkimus. Acta Forestalia Fennica vol. 33 no. 1 article id 7210. https://doi.org/10.14214/aff.7210
English title: Morphological study of Scots pine root system.
Original keywords: mänty; Pinus sylvestris; kasvupaikka; paalujuuri
English keywords: forest site type; taproot; vertical root system
Abstract | View details | Full text in PDF | Author Info

The root systems of 192 Scots pine (Pinus sylvestris L.) sample trees were dug out and measured in Säyneinen, Rautavaara and Pielijsäjvi in the Central Finland and Orivesi, Teisko and Hämeenkyrö in the Southern Finland. The volume of root system of Scots pine was always smaller than the stem, varying from 15% to 94% of the stem volume. The ratio is smaller in dense stands. The type of soil of the site affects how the central root system (tap root and the inner vertical roots) develop. This reflect the adaptability of the root system to different growth conditions. The root system may, for instance, substitute the tap root with stronger inner roots.

PDF includes a summary in English.

  • Laitakari, E-mail: el@mm.unknown (email)
article id 7209, category Article
Aarne Boman. (1927). Tutkimuksia männyn paksuuskasvun monivuotisista vaihteluista Suomen eri osista kerätyn aineiston perusteella. Acta Forestalia Fennica vol. 32 no. 4 article id 7209. https://doi.org/10.14214/aff.7209
English title: Studies on annual variations of diameter growth of Scots pine in different parts of Finland.
Original keywords: suo; mänty; Pinus sylvestris; läpimitan kasvu; vuosilusto; auringonpilkut
English keywords: peatland; annual ring; growth ring; sunspots
Abstract | View details | Full text in PDF | Author Info

Discs were collected from sample trees of Scots pine (Pinus sylvestris L.) in different types of peatlands and mineral soil sites in Kajaani, Rovaniemi, Kuusamo; Suojärvi, Pielisjärvi, Evo and Lokalahti in Finland. The growth ring series of the different areas reach as far as in the 1600th century in some sample plots. The diameter growth shows patterns that repeat in cycles of 7, 11, 21, 35 and 70 years. However, the cycles are not exactly equally long. The average lengths of the cycles are relatively similar both in peatlands and in mineral soil sites.

The PDF includes a summary in German.

  • Boman, E-mail: ab@mm.unknown (email)
article id 7194, category Article
T. Heikkilä. (1925). Kasvututkimuksia Perä-Pohjolasta. Acta Forestalia Fennica vol. 29 no. 4 article id 7194. https://doi.org/10.14214/aff.7194
English title: Growth studies in the northernmost Finland.
Original keywords: kuusi; Picea abies; mänty; Pinus sylvestris; arvokasvu; laatukasvu
English keywords: Norway spruce; Scots pine; value increment; quality increment; Perä-Pohjola
Abstract | View details | Full text in PDF | Author Info

There is little knowledge about the value increment of the stands that are about to become mature for felling. Sample plots were measured in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands in the most common forest site types in Rovaniemi, in northernmost Finland. Sample trees were chosen from dominant and codominant trees of the stand.

The value increments for the stands were generally very low. The average rotation of the studied stands would be 160 years. In the better forest site type, the increments of basal-area, volume and form height decrease slowly as the diameter of the tree increases. The value increment can give valuable information for intermediate fellings. They should be targeted mainly to large codominant trees and partly also in dominant trees that do not yet give logs, because their value increment is low.

The PDF includes a summary in German.

  • Heikkilä, E-mail: th@mm.unknown (email)
article id 7094, category Article
S. E. Multamäki. (1923). Tutkimuksia ojitettujen turvemaiden metsänkasvusta. Acta Forestalia Fennica vol. 27 no. 1 article id 7094. https://doi.org/10.14214/aff.7094
English title: Studies on the growth of drained peatlands in Finland.
Original keywords: ojitus; mänty; Pinus sylvestris; läpimitan kasvu; pituuskasvu; turvekangas
English keywords: Scots pine; height growth; drained peatland; diameter growth; draining
Abstract | View details | Full text in PDF | Author Info

Only about 24,000 hectares of peatlands have been drained in the state lands by the 1921. The aim of this study was to define how much the growth of the trees in the drained peatland revives. Sample plots were measured in previously drained peatlands that had sufficient Scots pine (Pinus sylvestris L.) tree stand. A stem analysis was performed to one of the sample trees. The evenness of the stands was dependent on how evenly the peatlands had dried when the stand was regenerated. Thus, the sample stands were not always fully stocked. However, they had capacity to develop towards evenly structured forests as the peatlands continued to dry further. The diameter and height growth of the dried peatlands have corresponded the similar stands in mineral soil sites. In trees that have grown stunted in the peatlands, the diameter growth seems to increase faster than the height growth. The volume growth is slightly smaller than in the similar mineral soil sites due to less favorable stem form. After the draining, the roots of the trees continued to grow from the old branches of root, but start then to form new roots. When the ground water level drops, the root layer grows deeper.

The PDF includes a summary in German.

  • Multamäki, E-mail: sm@mm.unknown (email)
article id 7049, category Article
Erkki Laitakari. (1920). Tutkimuksia sääsuhteiden vaikutuksesta männyn pituus- ja paksuuskasvuun. Acta Forestalia Fennica vol. 17 no. 1 article id 7049. https://doi.org/10.14214/aff.7049
English title: Studies on the effect of weather conditions on diameter and height growth of Scots pine.
Original keywords: mänty; Pinus sylvestris; läpimitan kasvu; pituuskasvu
English keywords: height growth; diameter growth
Abstract | View details | Full text in PDF | Author Info

The height and diameter growth measured from different Scots pine (Pinus sylvestris L.) stands in Southern Finland was compared with meteorological information. The height growth benefits from warm weather in late summer in the previous year, and especially from high temperatures in June. Precipitation or the temperature in the same year did not affect the height growth. Diameter growth benefits from high temperatures in the spring of the same year, especially in April. High precipitation in the spring has in some cases negative impact on the diameter growth. The different combinations of precipitation and temperature can have variable effects on tree growth. In the diameter growth was seen a periodicity that coincides with sunspots.

  • Laitakari, E-mail: el@mm.unknown (email)
article id 7048, category Article
O. J. Lakari. (1920). Tutkimuksia männyn muodosta. Acta Forestalia Fennica vol. 16 no. 6 article id 7048. https://doi.org/10.14214/aff.7048
English title: Studies on the stem and crown form of Scots pine.
Original keywords: mänty; Pinus sylvestris; runkomuoto; latvuskerros
English keywords: canopy layer; stem form; crown class
Abstract | View details | Full text in PDF | Author Info

Crown class is useful tool both in forest management and forest mensuration. The study presents a detailed crown classification for Scots pine (Pinus sylvestris L.). It was used to classify the sample trees prior detailed measurements of the crown and stem form. The stem form of a tree was dependent on which canopy layer it belonged. This relation was detected on both Vaccinium and Calluna site type forests. In addition, the stem tapers faster in poorer forest site types compared to better sites. The shorter the self-pruned part of the stem is, the faster the stem tapers. According to the study, the stems of stunted trees taper faster than trees of other crown classes. Also the age group affects stem form.

The PDF includes a summary in German.

  • Lakari, E-mail: ol@mm.unknown (email)
article id 7042, category Article
Yrjö Ilvessalo. (1920). Kasvu- ja tuottotaulut Suomen eteläpuoliskon mänty-, kuusi- ja koivumetsille. Acta Forestalia Fennica vol. 15 no. 4 article id 7042. https://doi.org/10.14214/aff.7042
English title: Growth and yield tables for the Scots pine, Norway spruce and birch in the southern part of Finland.
Original keywords: Etelä-Suomi; kuusi; Picea abies; mänty; Pinus sylvestris; metsätyyppi; koivu; Betula sp.; Keski-Suomi; kasvu- ja tuotostaulukko; runkolukusarja
English keywords: Southern Finland; forest site type; stem frequency distribution series; Central Finland
Abstract | View details | Full text in PDF | Author Info

The first proper growth and yield tables were prepared in Finland already in 1872, but they have been used little as the needs of forestry and forest sciences increased. One of the problems of the old yield tables was how the site quality classes are determined. The new growth and yield tables use the forest site type classification, which enables the use of same site types for all tree species. This makes it possible to compare the growth of different tree species in same kind of sites. The tables also use stem frequency distribution series. In the first stage, the tables were prepared for Southern and Central Finland.

The PDF includes a summary in German.

  • Ilvessalo, E-mail: yi@mm.unknown (email)
article id 7036, category Article
I. Lassila. (1920). Tutkimuksia mäntymetsien synnystä ja kehityksestä pohjoisen napapiirin pohjoispuolella. Acta Forestalia Fennica vol. 14 no. 3 article id 7036. https://doi.org/10.14214/aff.7036
English title: Studies on the regeneration and development of Scots pine forests north of the arctic circle.
Original keywords: luontainen uudistuminen; mänty; Pinus sylvestris; siemensato; käpy
English keywords: natural regeneration; cone; seed yield
Abstract | View details | Full text in PDF | Author Info

The frequency of years when Scots pine (Pinus sylvestris L.) produces cones and seeds affects its reproduction in the north. The study area covered most of the pine lands in Northern Finland. Scots pine seems to be able to produce cones relatively often in the north. The amount of seeds produced in one year was, however, not sufficient to produce a dense seedling stand. Thus, the natural pine stands contain usually trees in different ages-classes, which have germinated in different years. The cone production is highest in 150-170 years old trees. Pine also needs warm summers to produce viable seeds. Brush fires avail the growth of seedlings, because they clear of ground vegetation that hinders germination of seeds. The seedlings need also moisture to survive; good regeneration years have often had rainy summers.

The PDF includes a summary in German.

  • Lassila, E-mail: il@mm.unknown (email)
article id 7026, category Article
August Renvall. (1919). Suojametsäkysymyksestä VI. Asutusolojen järjestely mäntymetsärajaseuduilla. Acta Forestalia Fennica vol. 11 no. 6 article id 7026. https://doi.org/10.14214/aff.7026
English title: Protection forests VI.
Original keywords: mänty; Pinus sylvestris; asutus; kotitarvepuu; metsäraja
English keywords: Scots pine; household timber; timber line; local population
Abstract | View details | Full text in PDF | Author Info

The sixth part of the six-article series about protection forest in the Northern Finland is a review of the population and villages situated in the Scots pine (Pinus sylvestris L.) timber line area, and how private use of wood can be coordinated with the protection of pine timber line. Both the preservation of forests and the use of the forest as the source of timber and fuel wood in the timber line area are essential for the local communities, especially because in the area there is are few livelihoods. The article includes a proposal for a decree for new settlements in the northern protection forest area.

The article is divided in six parts. A German summary is in a separate PDF.

  • Renvall, E-mail: ar@mm.unknown (email)
article id 7025, category Article
August Renvall. (1919). Suojametsäkysymyksestä V. Metsänhoidon perusteet varsinaisella mäntymetsärajavyöhykkeellä. Acta Forestalia Fennica vol. 11 no. 5 article id 7025. https://doi.org/10.14214/aff.7025
English title: Protection forests V.
Original keywords: luontainen uudistuminen; metsänhoito; mänty; Pinus sylvestris; siementuotanto; metsäraja
English keywords: Scots pine; household timber; timber line; local population
Abstract | View details | Full text in PDF | Author Info

The fifth part of the six-article series about protection forest in Northern Finland outlines sustainable forest management practices for the Scots pine (Pinus sylvestris L.) forests in the pine timber line area. The author stresses the need to secure the seed production and regeneration capacity of the forests, and the growth and protection of seedlings. At the same time, the local communities’ need for timber has to be taken into account when considering the means to protect the pine forests. The main principle is not to cut more trees than has been regenerated during the time period between good seed years. The article outlines good forest management practices for the timber line area.

The article is divided in six parts. A German summary is in a separate PDF.

  • Renvall, E-mail: ar@mm.unknown (email)
article id 7024, category Article
August Renvall. (1919). Suojametsäkysymyksestä IV. Poronlaidunnan järjestely suojametsäalueella. Acta Forestalia Fennica vol. 11 no. 4 article id 7024. https://doi.org/10.14214/aff.7024
English title: Protection forests IV.
Original keywords: luontainen uudistuminen; mänty; Pinus sylvestris; metsäraja; poronhoito
English keywords: natural regeneration; Scots pine; grazing; timber line; reindeer
Abstract | View details | Full text in PDF | Author Info

This fourth part of the six-article series about protection forest in the Northern Finland is a proposal for organizing reindeer grazing to enable scots pine (Pinus sylvestris L.) regeneration near the timber line. Protection forests in the Northern Finland cover third of the natural pastures of reindeer in the area. In these areas reindeer grazing can harm the young pine seedlings. The proposal suggests temporary restrictions in grazing in the coniferous forests. Also, in the northernmost parts of Lapland the pine timberline area would be used only as winter pastures. Regional limits should be set for the number of reindeer. Also the ownership of reindeer herds and herding coopearatives included problematic issues that should be solved.

The article is divided in six parts. A German summary is in a separate PDF.

  • Renvall, E-mail: ar@mm.unknown (email)
article id 7023, category Article
August Renvall. (1919). Suojametsäkysymyksestä III. Metsän suojeleminen kuloilta. Acta Forestalia Fennica vol. 11 no. 2-3 article id 7023. https://doi.org/10.14214/aff.7023
English title: Protection forests III.
Original keywords: mänty; Pinus sylvestris; lainsäädäntö; metsäpalo; metsäraja; palontorjunta
English keywords: Scots pine; forest fire; legislation; timber line; fire protection
Abstract | View details | Full text in PDF | Author Info

The third part of the six-article series about protection forest in Northern Finland describes prevention of forest fires in the pine timber line area. The article gives a proposal for a forest fire decree. According to the proposal, lighting a campfire should be prohibited in dry and windy times. Vegetation should be cleared around a campfire in the summertime. The local people should be obliged to help to extinguish any forest fire, and given compensation for the work. The compensation would be claimed from the person who lit the fire, if that is known. A fine is collected if forest fire breaks out by negligence. 

The article is divided in six parts. The parts II and III of the article series are included in the same PDF. A German summary is in a separate PDF.

  • Renvall, E-mail: ar@mm.unknown (email)
article id 7022, category Article
August Renvall. (1919). Suojametsäkysymyksestä II. Suojametsäjärjestelmän tarkoitusperät ja edellytykset. Acta Forestalia Fennica vol. 11 no. 2-3 article id 7022. https://doi.org/10.14214/aff.7022
English title: Protection forests II.
Original keywords: luontainen uudistuminen; mänty; Pinus sylvestris; metsäraja
English keywords: natural regeneration; Scots pine; timber line
Abstract | View details | Full text in PDF | Author Info

The second part of the six-article series about protection forest in Northern Finland outlines the principles of protecting Scots pine (Pinus sylvestris L.) timber line. The protected areas should include at least all of the viable pine stands and those birch (Betula sp.) lands that are necessary to safeguard fuel wood supply in the pine forest zone. Outside the actual pine forest zone also those birch stands that are near populated regions should be protected to secure sustainable fuel wood supply. Third, south and down of the pine forest zone should be protected pine forest stands and adjacent open fell areas where forests are especially vulnerable. A new protection forest commission should be established to execute the protection forest legislation.

The article is divided in six parts. The parts II and III of the article series are included in the same PDF. A German summary is in a separate PDF.

  • Renvall, E-mail: ar@mm.unknown (email)
article id 7021, category Article
August Renvall. (1919). Suojametsäkysymyksestä I. Mäntymetsän elinehdot sen pohjoisrajalla sekä tämän rajan alenemisen syyt. Acta Forestalia Fennica vol. 11 no. 1 article id 7021. https://doi.org/10.14214/aff.7021
English title: Protection forests I.
Original keywords: mänty; Pinus sylvestris; suojametsät; metsänraja
English keywords: Scots pine; timber line; protection forest
Abstract | View details | Full text in PDF | Author Info

The article aims to give a proposal on how to organize a protection forest system to protect the pine timber line in the northernmost Finland. In this first part of the six-article series is described the range and biology of Scots pine (Pinus sylvestris L.) in the timber line area, and human actions influencing the species in the area. The southward shift of Scots pine timber line cannot be explained by change of climate. The main factors are too intensive fellings, reindeer husbandry and forest fires. The poor reproduction of pine in Lapland makes it vulnerable to disturbances. The trees produce viable seeds in average only every 100 years. Thus, effective measures are needed to protect the existing pine forests in the area.

The article is divided in six parts. A German summary is in a separate PDF.

  • Renvall, E-mail: ar@mm.unknown (email)
article id 7527, category Article
August Renvall. (1913). The periodic variation of the regeneration of pine (Pinus sylvestris) at the polar tree line. Acta Forestalia Fennica vol. 1 no. 2 article id 7527. https://doi.org/10.14214/aff.7527
Keywords: Pinus sylvestris; seed production; reproduction of pine; polar tree line; cone formation
Abstract | View details | Full text in PDF | Author Info

The study deals with the preconditions for natural regeneration of the pine at the polar tree line in northern Finland and Sweden. The data has been collected in three summers from 1909 to 1911 in areas of Inari and Utsjoki in Finland and Kaaresuvanto, Jukkasjärvi und Pajala in Sweden. The yearly variation of seed production of pine is studied and compared with the age of the stand, site factors and weather conditions.

Intensity of reproduction is dependent on different preconditions for pistils and stamens and hence the total reproduction (formation of cones) can vary very much depending on the weather.

According the study, the formation of cones varies yearly and is particularly strong every three to four years.  Supposedly the same model applies to whole polar tree line of the Fennoscandia. There seem to be no difference between northern and southern parts of Scandinavia when it comes to frequency of good cone years though they not always occur in the same years.
  • Renvall, E-mail: ar@mm.unknown (email)
article id 7519, category Article
Jori Uusitalo. (1997). Pre-harvest measurement of pine stands for sawing production planning. Acta Forestalia Fennica no. 259 article id 7519. https://doi.org/10.14214/aff.7519
Keywords: Pinus sylvestris; diameter distribution; height models; crown height estimation; forest sampling; lumber quality prediction
Abstract | View details | Full text in PDF | Author Info

To enhance the utilization of the wood, the sawmills are forced to place more emphasis on planning to master the whole production chain from the forest to the end product. One significant obstacle to integrating the forest-sawmill-market production chain is the lack of appropriate information about forest stands. Since the wood procurement point of view in forest planning systems has been almost totally disregarded there has been a great need to develop an easy and efficient pre-harvest measurement method, allowing separate measurement of stands prior to harvesting. The main purpose of this study was to develop a measurement method for Scots pine (Pinus sylvestris L.) stands which forest managers could use in describing the properties of the standing trees for sawing production planning.

Study materials were collected from ten Scots pine stands located in North Häme and South Pohjanmaa, in Southern Finland. The data comprise test sawing data on 314 pine stems, diameter at breast height (dbh) and height measures of all trees and measures of the quality parameters of pine sawlog stems in all ten study stands as well as the locations of all trees in six stands. The study was divided into four sub-studies which deal with pine quality prediction, construction of diameter and dead branch height distributions, sampling designs and applying height and crown height models. The final proposal for the pre-harvest measurement method is a synthesis of the individual sub-studies.

Quality analysis resulted in choosing dbh, distance from stump height to the first dead branch, crown height and tree height as the most appropriate quality characteristics of Scots pine. Dbh and dead branch height are measured from each pine sample tree while height and crown height are derived from dbh measures by aid of mixed height and crown height models. Pine and spruce diameter distribution as well as dead branch height distribution are most effectively predicted by the kernel function. Roughly 25 sample trees seem to be appropriate in pure pine stands. In mixed stands the number of sample trees needs to be increased in proportion to the intensity of pines in order to attain the same level of accuracy.

  • Uusitalo, E-mail: ju@mm.unknown (email)
article id 7525, category Article
Pertti Hari, Johan Ross, Marja Mecke. (1996). Production process of Scots pine. Acta Forestalia Fennica no. 254 article id 7525. https://doi.org/10.14214/aff.7525
Keywords: Pinus sylvestris; photosynthesis; Scots pine; allocation; structure; annual cycle; irradiance; stand models; geographical features
Abstract | View details | Full text in PDF | Author Info

The accompanying collective research report is the result of the research project in 1986–90 between the Finnish Academy and the former Soviet Academy of Sciences. The project was organized around common field work in Finland and in the former Soviet Union, and theoretical analyses of tree growth determining processes. Based on theoretical analyses, dynamic stand growth models were made and their parameters were determined utilizing the field results.

Annual cycle effects the tree growth. Our theoretical approach was based on adaptation to local climate conditions from Lapland to South Russia. The initiation of growth was described as a simple low and high temperature accumulation driven model. The model was linked with long-term temperature data.

Analysis of field measurements of CO2 exchange showed that irradiance is the dominating factor causing variation in photosynthetic rate in natural conditions during summer. The penetration of irradiance into Scots pine (Pinus sylvestris L.) canopy is a complicated phenomenon. A moderately simple but balanced forest radiation regime sub-model was constructed.

The common field excursions in different geographical regions resulted in a lot of experimental data of regularities of woody structure. The water transport seems to be a good common factor to analyse these properties of tree structure. The produced theoretical and experimental material was utilized in the development of stand growth model that describes the growth and development of Scots pine stands in Finland and the former Soviet Union. The core of the model is carbon and nutrient balances. This means that carbon obtained in photosynthesis is consumed or growth and maintenance and nutrients are taken according to the metabolic need. Since the fundamental metabolic processes are the same in all locations, the same growth model structure can be applied in the large range of Scots pine. The model enables the analysis of geographical differences in the growth of Scots pine. The present approach enables utilization of structural and functional knowledge gained in places of intensive research, in the analysis of growth and development of any stand.

  • Hari, E-mail: ph@mm.unknown (email)
  • Ross, E-mail: jr@mm.unknown
  • Mecke, E-mail: ph@mm.unknown
article id 7685, category Article
Risto Ojansuu. (1993). Prediction of Scots pine increment using a multivariate variance component model. Acta Forestalia Fennica no. 239 article id 7685. https://doi.org/10.14214/aff.7685
Keywords: Pinus sylvestris; crown height; volume increment; bark volume; variance component models; multivariate models; stem curve models; tree form change
Abstract | View details | Full text in PDF | Author Info

Diameter and volume increment as well as change in stem form of Scots pine (Pinus sylvestris L.) were analysed to predict tree increment variables. A stem curve set model is presented, based on prediction of the diameters at fixed angles in a polar coordinate system. This model consists of three elementary stem curves: 1) with bark, 2) without bark, and 3) without bark five years earlier. The differences between the elementary stem curves are the bark curve and the increment curve. The error variances at fixed angles and covariances between the fixed angles are divided into between-stand and within-stand components. Using principal components, the between-stand and within-stand covariance matrices are condensed separately for stem curve with bark, bark curve and increment curve. The two first principal components of the bark curve describe the vertical change in Scots pine bark type and the first principal component of the increment curve describes the increment rate. The elementary stem curves, bark curve and increment curve as well as corresponding stem volumes, bark volume and volume increment can be predicted for all trees in the stand with free choice of sample tree measurements. When only a few sample trees are measured, the stem curve set model gives significantly more accurate predictions of bark volume and volume increment for tally trees than does the volume method, which is based on the differences between two independent predictions of volume. The volume increment of tally trees can be predicted as reliably with as without measurement of sample tree height increment.

The PDF includes a summary in English.

  • Ojansuu, E-mail: ro@mm.unknown (email)
article id 7683, category Article
Alpo Luomajoki. (1993). Climatic adaptation of Scots pine (Pinus sylvestris L.) in Finland based on male flowering phenology. Acta Forestalia Fennica no. 237 article id 7683. https://doi.org/10.14214/aff.7683
Keywords: Pinus sylvestris; adaptation; anthesis; flowering phenology; pollen recording; heat sum; reinvasion
Abstract | View details | Full text in PDF | Author Info

Timing of anthesis in 21 Scots pine (Pinus sylvestris L.) stands from 14 localities in Finland was studied at the canopy level in 1963-74. Distribution of pollen catches were compared with the normal Gaussian distribution. The basis for the timing studies was the 50 per cent point of the anthesis-fitted normal distribution. Development was characterized in calendar days, in degree days (>5°C) and in period units. The count of each unit began on March 19 (included).

Period unit was found to be the most accurate delineation of development. Locally, calendar days were sometimes a more accurate parameter. Anthesis in Northern Finland occurred at a later date than in the south as was expected, but at lower heat sum. The variation in the timing of anthesis and the variation of pollen catches increased northwards. The geographical correlations calculated against distances measured along simulated post-glacial migration routes were stronger than purely latitudinal correlations. Effects of the reinvasion of Scots pine into Finland are thus still visible in pine populations.

The proportion of the average annual heat sum needed for anthesis grew rapidly above a latitude of 63° even though the heat sum needed for anthesis decreased towards the timberline. In light of flowering phenology, it seemed probable that the northern populations in Scots pine in Finland have still not completely adapted to the prevailing cold climate at these latitudes. A moderate warming of the climate would therefore be beneficial for Scots pine.

The PDF includes a summary in Finnish.

  • Luomajoki, E-mail: al@mm.unknown (email)
article id 7681, category Article
Eero Nikinmaa. (1992). Analyses of the growth of Scots pine: matching structure with function. Acta Forestalia Fennica no. 235 article id 7681. https://doi.org/10.14214/aff.7681
Keywords: Pinus sylvestris; Scots pine; pipe model; nutrients; heartwood; growth models; carbon budget; structure; partitioning of growth; growht
Abstract | View details | Full text in PDF | Author Info

A theoretical framework to analyse the growth of Scots pine (Pinus sylvestris L.) is presented. Material exchange processes and internal processes that transport, transform and consume materials are identified as the components of growth. Hierarchical system is lined out. Momentary uptake of material at a single exchange site depends on the environmental condition next to the exchange site, the internal state of the biochemical system of the plant and the structure of the plant. The internal state depends on the exchange flows over period of time and the structural growth depends on the internal state. The response of these processes to the fluxes is controlled by the genetic composition of the plant.

The theoretical framework is formulated into a mathematical model. A concept of balanced internal state was applied to describe the poorly known internal processes. Internal substrate concentrations were assumed to remain constant but tissue-specific. A linear relationship between the quantity of foliage and wood cross-sectional area was assumed to describe balanced formation of structure. The exchange processes were thus described as a function of external conditions. The stand level interactions were derived from shading and effects of root density on nutrient uptake.

The approach was tested at different levels of hierarchy. Field measurements indicated that the hypothesis of the linear relationship described well the regularities between foliage and sapwood of a tree within a stand when measured at functionally corresponding height. There was considerable variation in the observed regularities in the range of geographic occurrence of Scots pine. Model simulations gave a realistic description of stand development in Southern Finland. The same model was also able to describe growth differences in Lapland after considering the effect of growing season length in the parameter values. Simulations to South Russia indicate stronger deviation from the observed patterns.

The simulations suggest interesting features of stand development. They indicate strong variability in the distribution of carbohydrates between tree parts during stand development. Internal circulation of nutrients and the reuse of the same transport structure by various needle generations had a strong influence on the simulation results.

The PDF includes a summary in Finnish.

  • Nikinmaa, E-mail: en@mm.unknown (email)
article id 7677, category Article
Risto Heikkilä, Timo Mikkonen. (1992). Effects of density of young Scots pine (Pinus sylvestris) stand on moose (Alces alces) browsing. Acta Forestalia Fennica no. 231 article id 7677. https://doi.org/10.14214/aff.7677
Keywords: Pinus sylvestris; Scots pine; Alces alces; stand density; feeding behaviour; moose browsing; plant phenology
Abstract | View details | Full text in PDF | Author Info

The study was carried out at Padasjoki, Southern Finland, where moose (Alces alces L.) density on the winter range had been over 1.5 individuals/km2. Moose browsing intensity, expressed in terms of number of twigs eaten and biomass used, increased with stand density (biomass). Total biomass consumption (dry weight) per sample plot and per sapling. The number of bites increased, but the percentage biomass removed did not differ when stand density increased. A relatively large bite size was observed on the plots of low stand density. The quantity of food, which on average was of relatively low quality, was obviously important due to the benefit gained through reducing the search time.

The nutritive value of the browse, expressed in terms of chemical compounds indicating low food digestibility, was lower in the dense than in the sparse Scots pine stand. However, the amount of crude protein and arginine were relatively high in the dense stand. We concluded that shading affected the nutritional status of saplings on high density plots.

Although the biomass removed by moose per sapling was high for low density plots, the remaining biomass was larger than that on the high-density plots owing to the relatively large twig biomass of saplings. The number of saplings per hectare without main stem breakage increased significantly as stand density increased.

The PDF includes a summary in Finnish.

  • Heikkilä, E-mail: rh@mm.unknown (email)
  • Mikkonen, E-mail: tm@mm.unknown
article id 7669, category Article
Leena Finér. (1991). Effect of fertilization on dry mass accumulation and nutrient cycling in Scots pine on an ombrotrophic bog. Acta Forestalia Fennica no. 223 article id 7669. https://doi.org/10.14214/aff.7669
Keywords: Pinus sylvestris; biomass; fertilization; litterfall; drained peatland; nutrients; production; accumulation; nutrient uptake
Abstract | View details | Full text in PDF | Author Info

The first three-year effects of PK(MgB) and NPK(MgB) fertilization on the dry mass accumulation and nutrient cycling were studied in a Scots pine (Pinus sylvestris L.) stand growing on a drained low-shrub pine bog in Eastern Finland. The total dry mass of the tree stand before fertilization was 78 tn/ha, of which the above-ground compartments accounted for 69%. The annual above-ground dry mass production was 6.3 tn/ha, 51% of it accumulating in the tree stand.

The study period was too short for detecting any fertilization response in the stems. The total dry mass accumulation was not affected, because the increase in foliar and cone dry masses after both fertilization treatments, and that of the living branches after NPK fertilization, were compensated by the decrease in the dry mass of dead branches.

The nutrients studied accounted for 392 kg/ha (0.49%) of the total dry mass of the tree stand before fertilization. The amounts were as follows; N 173 kg/ha (44%), Ca 90 kg (23%), K 58 kg/ha (15%). The rest (18%) consisted of P, Mg, S and micronutrients combined. The unfertilized trees took up the following amounts of nutrients of the soil: N 15.6, Ca 12.8, K 4.1, P 1.3, MG 1.7, and S and Mn 1.5 kg/ha. The uptake of Fe and Zn was 510 and 130 g/ha and that of B and Cu less than 100 g/ha. More than 50% of the nutrient uptake, except for that of K and Fe, was released in litterfall. The results indicated very efficient cycling of K, Mn and B between the soil and trees.

The fertilized stands accumulated more N, P, K and B than the unfertilized ones during the tree-year study period. The increased accumulation corresponded to 35% (52 kg/ha) of the N applied on the NPK fertilized plots, 10% of the P, 25% of the K and 10% of the B on the PK and NPK fertilized plots. The increased amount of B released in litterfall after fertilization was equivalent to 4% of the applied B. Fertilization inhibited the uptake of Mn and Ca.

The PDF includes a summary in Finnish.

  • Finér, E-mail: lf@mm.unknown (email)
article id 7663, category Article
Anne Sairanen. (1990). Site characteristics of Scots pine stands infected by Gremmeniella abietina in Central Finland. 1: Mineral soil sites. Acta Forestalia Fennica no. 216 article id 7663. https://doi.org/10.14214/aff.7663
Keywords: Pinus sylvestris; Scots pine; damage risk; Gremmeniella abietina; site classification; pathogens; Ascocalyx abietina
Abstract | View details | Full text in PDF | Author Info

Mineral soil sites where Scots pine (Pinus sylvestris L.) were suffering from Gremmeniella abietina die-back (Lagerb.) M. Morelet. were characterized and classified in Central Finland. The tree stand, ground vegetation, soil type and site topography were described in 163 sample plots in 16 stands. The sites were classified according to system developed by Cajander and numerically using TWINSPAN analysis based on the ground vegetation. The site topography of severely damaged stands was checked from colour infrared aerial photographs. The disease was most severe in depressions and frost pockets. Apart from topography no significant correlations were found between disease severity and site factors. No typical vegetational pattern of forest type of the severely affected stands could be detected. Most of the stands were growing on medium-coarse, unfertile soil with a rather thick humus layer.

The PDF includes a summary in Finnish.

  • Sairanen, E-mail: as@mm.unknown (email)
article id 7662, category Article
Antti Uotila. (1990). Infection of pruning wounds in Scots pine by Phacidium coniferarum and selection of pruning season. Acta Forestalia Fennica no. 215 article id 7662. https://doi.org/10.14214/aff.7662
Keywords: Pinus sylvestris; pruning; pathogen; Phacidium coniferarum; pruning season; canker
Abstract | View details | Full text in PDF | Author Info

The Scots pine (Pinus sylvestris L.) pruning experiments were established in different geographical regions of Finland. The pines were pruned in 16 different times during the year. Half of the trees were inoculated with conidia of Phacidium coniferarum (Hahn). Annual cankers were produced in the inoculated trees pruned during October–December. The safe pruning season ended in autumn when the five-day mean temperature decreased below +7°C. The unsafe pruning season terminated when the temperature remained permanently over 0°C. Dry-pruned branches were infected only if the phloem had been wounded. The mycelia of the fungus were pathogenic in the phloem in the inoculations made from October to March. The fungus occurred commonly in slash and in pines wounded during the autumn. The fungus has a one-year life cycle.

The PDF includes a summary in Finnish.

  • Uotila, E-mail: au@mm.unknown (email)
article id 7660, category Article
Heikki Hänninen. (1990). Modelling bud dormancy release in trees from cool and temperate regions. Acta Forestalia Fennica no. 213 article id 7660. https://doi.org/10.14214/aff.7660
Keywords: Pinus sylvestris; Picea abies; climatic adaptation; annual cycle; bud dormancy; quiescence; rest; growth competence
Abstract | View details | Full text in PDF | Author Info

The premises of several models obtained from literature on bud dormancy release in trees from cool and temperate regions differs from each other with respect to responses to air temperature during the rest period of the buds. The predicted timing of bud burst in natural conditions varied among the models, as did the prediction of the models for the outcome of a chilling experiment.

Experimental results with two-year old seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) did not agree with any of the models. The experimental results also deviated from abundand earlier findings, which also disagreed with any of the models. This finding suggests that Finnish provenances of Scots pine and Norway spruce differ from more southern provenances with respect to temperature regulation of bud dormancy release.

A synthesis model for the effects of air temperature on bud dormancy release in trees was developed on the basis of the previous models and the experimental results of both the present and previous studies. The synthesis model contains part of the original models as special cases. The parameters of the synthesis model represent several aspects of the bud dormancy release of trees that should be addressed separately with each species and provenance in experimental studies. Further aspects of dormancy release were discussed, in order to facilitate further development of the models.

The PDF includes a summary in Finnish.

  • Hänninen, E-mail: hh@mm.unknown (email)
article id 7659, category Article
Ari Lääperi. (1990). Hoidettujen talvilaitumien vaikutus hirvituhoihin mäntytaimikoissa. Acta Forestalia Fennica no. 212 article id 7659. https://doi.org/10.14214/aff.7659
English title: Effect of winter feeding on moose damage to young Scots pine stands.
Original keywords: mänty; hirvituhot; männyntaimikot; talviruokinta
English keywords: Pinus sylvestris; Alces alces; seedling stands; feeding; moose damage; forest plantations
Abstract | View details | Full text in PDF | Author Info

The establishment of moose (Alces alces L.) winter feeding sites, their utilization and their effect on damage to young Scots pine (Pinus sylvestris L.) plantations was studied in Ruokolahti-Imatra area in Eastern Finland in 1987–89. During the period, the density in the area was about 3–5 moose/ 1,000 ha.

Six feeding sites were established by fertilization, offering mineral lics and the tops of aspen and Scot pine and by salting the tops of pine. The moose preferred the feeding site to control areas during both summer and winter. In winter browsing was very heavy, especially in those areas located in or close to traditional wintering areas. In winter no moose were seen in the summer habitats.

The extent of, and fluctuations in moose damage were studied in 47 Scots pine plantations in the immediate surroundings of the feeding sites (29 plantations), control areas (18 plantations) and also 68 randomly selected pine plantations. Before the experiment began in 1987 four plantations had been seriously damaged. During the study period only one plantation was seriously damaged. However, it could not be conclusively proved that damage to the pine plantations had been reduced as a result of the feeding sites. The results of the study can be put into practice elsewhere to create better living conditions for moose in their winter habitats. However, the food offered at the feeding site should be in the right proportion to the number of animals wintering in the area, so that the risk of damage to nearby plantations would be kept as small as possible.

The PDF includes a summary in Finnish.

  • Lääperi, E-mail: al@mm.unknown (email)
article id 7648, category Article
Markku Nygren. (1987). Germination characteristics of autumn collected Pinus sylvestris seeds. Acta Forestalia Fennica no. 201 article id 7648. https://doi.org/10.14214/aff.7648
Keywords: Pinus sylvestris; Scots pine; seed maturation; seed germination; seed dormancy; chilling requirement
Abstract | View details | Full text in PDF | Author Info

Germination tests in varying photoperiod- and temperature-regimes showed that for early autumn collections, germination of Scots pine (Pinus sylvestris L.) seeds is delayed, especially at low incubation temperature (+10°C) and in darkness. The presence of light during germination (8- or 24-hour photoperiod) or high incubation temperature (+20°C) enhanced germination. As autumn proceeded, a greater proportion of seed were able of germinate in darkness and also in low temperature regime. This result was consistent in both populations studied – in seeds from natural stand (Hyytiälä, Southern Finland) and in seeds from the Hyytiälä clone archive trees, growing in the same site.

An attempt was made to relate the development of germinability during autumn to previously accumulated chilling unit (optimum temperature +3.5°C) sum. Germination percent variation in subsequent cone-collection could not, however, be explained with accumulated chilling.

The PDF includes a summary in Finnish.

  • Nygren, E-mail: mn@mm.unknown (email)
article id 7634, category Article
Heikki Smolander. (1984). Measurement of fluctuating irradiance in field studies of photosynthesis. Acta Forestalia Fennica no. 187 article id 7634. https://doi.org/10.14214/aff.7634
Keywords: Pinus sylvestris; photosynthesis; Scots pine; shoot geometry; microvariation in irradiance
Abstract | View details | Full text in PDF | Author Info

The problems caused by the temporal and spatial microvariation in irradiance during field measurements of photosynthesis are studied. It is concluded on the basis of variation analyses based on irradiance data measured in a Scots pine (Pinus sylvestris L.) stand that the microvariation should be measured by integrating it over the measurement time and space.

However, the curvlinearity of the light response of photosynthesis results in biased estimates when linear integration (mean irradiance) is used. The significance of the bias is examined using a simulation technique on irradiance material. Whether the actual integral of photosynthesis can be approximated with mathematical method is next studied. The method gave satisfactory results only for a low curvature response, but the latter method was applicable also to the high curvature response. However, both methods presuppose that the mean and variance are known. Measurement of the variance is based on integration of the second power.

A new method, where the nonlinearity problem is avoided, is presented to measure fluctuation of the irradiance. The method enables the shoot geometry to be taken into account and it is also applicable to transpiration studies.

The PDF includes a summary in Finnish.

  • Smolander, E-mail: hs@mm.unknown (email)
article id 7633, category Article
Helena Henttonen. (1984). The dependence of annual ring indices on some climatic factors. Acta Forestalia Fennica no. 186 article id 7633. https://doi.org/10.14214/aff.7633
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; precipitation; temperature; effective temperature sum; annual ring index
Abstract | View details | Full text in PDF | Author Info

The paper concerns relationship between climatic factors and annual ring indices mainly in Southern Finland. The studied index series were from papers of different authors and from different localities. The monthly mean temperatures and precipitation sums were derived from the measurements of meteorological stations. Effective temperature sums for different periods of the year were calculated from the monthly mean temperatures.

The autocorrelation functions were estimated for each index series. The autocorrelations at lag I were significant except for one series. Altogether the differences in the structures of the index series were noticeable, especially between the Scots pine (Pinus sylvestris L.) index series. The influence of climatic factors on the annual ring index variation was studied using cross correlation analysis, simple distributed lag models and transfer function-noise models.

The decisive factor for the annual ring index variation of Norway spruce (Picea abies (L.) H. Karst.) appears to be the effective temperature sum of the growing season. Warm periods during latter parts of previous summer had a negative effect on indices. For the variation of the Scots pine indices the most important climatic factors were the effective temperature sum of the latter part of the growing season and, especially on the arid sites, the precipitation sum during May-July.

The PDF includes a summary in Finnish.

  • Henttonen, E-mail: hh@mm.unknown (email)
article id 7632, category Article
Pekka Kauppi. (1984). Stress, strain, and injury : Scots pine transplants from lifting to acclimation on the planting site. Acta Forestalia Fennica no. 185 article id 7632. https://doi.org/10.14214/aff.7632
Keywords: Pinus sylvestris; Scots pine; planting; seedlings; root desiccation
Abstract | View details | Full text in PDF | Author Info

This paper is the final report of a study on the damage of tree transplants induced before the trees are planted in the field. The injury development is viewed as a transient rather than a ”step-like” process. The main objective of the study is to develop concepts and methods for recognizing and analysing the dynamic aspects of that process. The report consists of three parts: i) characterization of the environments to which the plants are exposed, ii) theoretical part of model development, and iii) experiments with bare-rooted Scots pine (Pinus sylvestris L.) transplants in which the model was applied.

The results of the first part indicate fast temporal variation of the environmental stress factors, and a slow response of the plant in terms of visible injury symptoms. A model is developed in the second part of the paper for analysing the relationship between the fast stress variables and the slow injury variables. The model is employed in the third part of the study for developing experiments in which the transplants were subjected to different stress conditions. The conclusions emphasize the hazardous role of root desiccation. Similar injury development was observed over a range of different planting sites. Controlling high temperatures during the transportation and storage of the plants was introduced as an indirect method for avoiding the risk of root desiccation.

The PDF includes a summary in Finnish.

  • Kauppi, E-mail: pk@mm.unknown (email)
article id 7628, category Article
Eljas Pohtila, Tapani Pohjola. (1983). Lehvästöruiskutuksen ajoitus kasvukauden aikana. Acta Forestalia Fennica no. 181 article id 7628. https://doi.org/10.14214/aff.7628
English title: The timing of foliage spraying during the growing season.
Original keywords: mänty; herbisidit; taimikonhoito; lehdistöruiskutus; havupuutaimikot
English keywords: Pinus sylvestris; Scots pine; herbicides; seedling stands; MCPA; spraying of foliage; clearing of seedling stands; Roundup; DM; softwood seedling stand; hardwood sprouts
Abstract | View details | Full text in PDF | Author Info

An attempt was made in the study to determine the annual periods available for foliage spraying when cleaning Scots pine (Pinus sylvestris L.) dominated seedling stands. The study was made in nine experimental fields which were established in different parts of Finland. The spraying was applied throughout the growing season by DM, MCPA and Roundup. The results were inventoried one year after the treatments.

The results showed that there were big differences both in the destruction of hardwood sprouts and in the survival of pine seedlings due to the time period of the spraying. Threshold points were observed in the range of effect of DM and MCPA. By means of these it is possible to time the spraying treatments in such a way that there remains only slight damage to pine, but hardwood sprouts are destroyed totally. The results varied with Roundup so much, among other things due to rain, that such threshold points could not be determined. This preparation both had a milder effect on the hardwood seedlings and caused slighter damage to pine than the other preparations.

In Sodankylä in Northern Finland, the pines attained a good resistance to arboricides when the efficient temperature sum of the growing season was 550, but in Punkaharju in Central Finland only when it was 850. The seed provenance of the seedlings had an effect on the resistance. The threshold temperature sums of resistance in pine were on the average 70–74% from the long-term average number of degree days at the origin of the seed. The effect on the hardwood trees grew weaker as the long-term average was filled. Resistance of pine followed with a specific lag the lignification of the shoot and the ceasing of the growth of the needles.

The PDF includes a summary in English.

  • Pohtila, E-mail: ep@mm.unknown (email)
  • Pohjola, E-mail: tp@mm.unknown
article id 7626, category Article
Aarne Nyyssönen, Risto Ojansuu. (1982). Metsikön puutavaralajirakenteen, arvon ja arvokasvun arviointi. Acta Forestalia Fennica no. 179 article id 7626. https://doi.org/10.14214/aff.7626
English title: Assessment of timber assortments, value and value increment of stands in Finland.
Original keywords: kuusi; mänty; hakkuulaskelma; arvokasvu; metsikön arvo; puutavaralajirakenne
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; timber assortment; stand development; valuation; cutting budget
Abstract | View details | Full text in PDF | Author Info

The paper is the final report of a study on the estimation of value increment and inherent variables of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands. The main aim was to obtain improved criteria for decision-making concerning the priority of stands for regeneration.

The construction of various estimation models and their reliability are discussed in detail. The study, together with some previous papers, has resulted in a system which on the basis of a number of easily assessed stand variables gives for the stands concerned the volume of stems, percentages of timber assortments, stumpage value, volume increment and value increment.

The following examples are given with regard to the practical application of the results, in addition to the determination of the relative maturity of stands: 1) The study of various trends in stand development; the comparison between the volume and value variables. 2) The estimation of timber assortments needed for a cutting budget, trees marked for felling etc. 3) The calculation of the value of forests.

The PDF includes a summary in English.

  • Nyyssönen, E-mail: an@mm.unknown (email)
  • Ojansuu, E-mail: ro@mm.unknown
article id 7624, category Article
Pertti Hari, Seppo Kellomäki, Annikki Mäkelä, Pirkko Ilonen, Markku Kanninen, Eeva Korpilahti, Markku Nygren. (1982). Metsikön varhaiskehityksen dynamiikka. Acta Forestalia Fennica no. 177 article id 7624. https://doi.org/10.14214/aff.7624
English title: Dynamics of early development of tree stand.
Original keywords: tiheys; mänty; metsikön rakenne; metsikön kehitys; valo-olosuhteet; yhteyttäminen
English keywords: Pinus sylvestris; stand structure; photosynthesis; Scots pine; density; stand development; light conditions
Abstract | View details | Full text in PDF | Author Info

The report concludes a series of studies on the early development of young Scots pine (Pinus sylvestris L.) stands. The basis assumption made in the study series was that the within-stand light regime is the main driving force for total tree growth and its allocation of photosynthates for crown, stem and root growth. An individual tree growing in a stand under a varying light regime which is controlled by the stand structure, is the basic unit used in the study. The photosynthesis of an individual tree is determined by the light regime. The stand is formed from individual trees.

The model is applied in simulation of the growth and development of tree stands. Several computer runs representing various densities, height distributions and tree species mixtures were carried out. Potential application areas, properties of the model and future needs of investigations are discussed.

The PDF includes a summary in English.

  • Hari, E-mail: ph@mm.unknown (email)
  • Kellomäki, E-mail: sk@mm.unknown
  • Mäkelä, E-mail: am@mm.unknown
  • Ilonen, E-mail: pi@mm.unknown
  • Kanninen, E-mail: mk@mm.unknown
  • Korpilahti, E-mail: ek@mm.unknown
  • Nygren, E-mail: mn@mm.unknown
article id 7618, category Article
Songkram Thammincha. (1981). Climatic variation in radial growth of Scots pine and Norway spruce and its importance in growth estimation. Acta Forestalia Fennica no. 171 article id 7618. https://doi.org/10.14214/aff.7618
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; radial growth; growth indices; climatic variation
Abstract | View details | Full text in PDF | Author Info

Variation in the radial growth of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) was studied in 10 localities in Southern Finland. The aim of the study was to utilize the information on variation in the growth indices for growth estimation, and to evaluate the relative accuracy of growth estimation based on the data from increment boring, in comparison to other methods.

The climatic variation in periodic growth (5-year-period) in Southern Finland is about 11% of the normal level. The results suggest that the data from 10 localities can be used in the computation of the index series for Southern Finland and that the data from 10 relascope plots are required in the study of the climatic variation in tree growth in a given locality. The standard error of the estimate in actual growth estimation for past and future periods by the stand function method is about 23%, the errors of the method involving increment boring being 6% and 16% respectively in past and future growth estimation. The respective methods yield about 20% and 13% error in average growth estimation. With aid of the average growth indices for Southern Finland in local growth estimation the accuracy is distinctly improved, the error being equal to 12% only, while the accuracy in other cases is slightly improved.

The PDF includes a summary in Finnish.

  • Thammincha, E-mail: st@mm.unknown (email)
article id 7616, category Article
Min-Sup Chung. (1981). Flowering characteristics of Pinus sylvestris L. with special emphasis on the reproductive adaptation to local temperature factor. Acta Forestalia Fennica no. 169 article id 7616. https://doi.org/10.14214/aff.7616
Keywords: Pinus sylvestris; Scots pine; flowering; climate; temperature; seed orchards; seed production; location
Abstract | View details | Full text in PDF | Author Info

Flowering time and characteristics of cones and seed development of Scots pine (Pinus sylvestris L.) plus tree clones originating from various parts of Finland and planted (grafts) in Southern Finland (61° 48’ N, 29° 19’ E) were studied during 1976-1978.

The flowering time (in terms of period unit (p.u.) sums for flowering) of the Scots pine plus tree clones showed characteristics specific to each population and the characteristics appear mainly adapted to the local temperature factor within Finland. Generally, the development of floral organs, cones and seed in the spring and summer seasons also showed a temperature dependence in that the reproductive organs are developed rapidly and/or favourably under higher temperature conditions within its optimum range.

In this respect, establishment of northern Scots pine seed orchards in Central or Southern Finland or an optimum flowering, and a favourable seed development with an optimum physiological reproductive isolation from surrounding Scots pine populations can be justified. Problem arising from the north-south transfer of seed orchards and the significance of trees’ growth rhythm are discussed in connection with tree improvement.

The PDF includes a summary in Finnish.

  • Chung, E-mail: mc@mm.unknown (email)
article id 7614, category Article
Leo. Heikurainen. (1980). Kuivatuksen tila ja puusto 20 vuotta vanhoilla ojitusalueilla. Acta Forestalia Fennica no. 167 article id 7614. https://doi.org/10.14214/aff.7614
English title: Drainage condition and tree stands on peatlands drained 20 years ago in Finland.
Original keywords: mänty; tilavuuskasvu; ojitetut suot; sarkaleveys; ojien kunto; pohjaveden pinta; ojasyvyys
English keywords: Pinus sylvestris; Scots pine; stand volume; ditch spacing; ditch depth; volume increment; groundwater depth; ditch condition
Abstract | View details | Full text in PDF | Author Info

The aim of this investigation was to examine the dependence of stand volume and increment on different growth factors on drained peatlands drained 20 years ago. Measurements were made in 1977-79 on 35 sample plots in Central Finland on relatively poor pine bogs with a thick peat layer.

It became evident that the stand volume, increment and radial growth and growth development are primarily functions of groundwater depth. Groundwater depth is dependent, in the first place, on ditch depth and ditch condition. With regard to the variation in ditch spacing (ca. 35-70 m) under examination, the effect of ditch spacing on the stand was insignificant. As a practical recommendation it was concluded that ditches should be kept deep enough (> 70 cm) in order to maintain undisturbed stand development.

The PDF includes a summary in English.

  • Heikurainen, E-mail: lh@mm.unknown (email)
article id 7604, category Article
Jukka Laine, Hannu Mannerkoski. (1980). Lannoituksen vaikutus mäntytaimikoiden kasvuun ja hirvituhoihin karuilla ojitetuilla nevoilla. Acta Forestalia Fennica no. 166 article id 7604. https://doi.org/10.14214/aff.7604
English title: Effect on fertilization on tree growth and elk damage in young Scots pine stands planted on drained, nutrient-poor open bogs in Finland.
Original keywords: ojitus; mänty; kasvu; hirvituhot; lannoitus; taimikot; typpi; nevat; fosfori
English keywords: Pinus sylvestris; fertilization; nitrogen; drained peatlands; Scots pine; growth; phosphorus; seedlings; elk damages; open pogs
Abstract | View details | Full text in PDF | Author Info

An attempt was made in this study to determine which nutrients and in what amounts should be used in the fertilization of Scots pine (Pinus sylvestris L.) seedling stands on nutrient-poor open bogs in order to obtain optimum seedling growth and to minimize the risk of elk damage.

The most important nutrient to improve seedling growth in the experiments was phosphorus. Already rather small amounts produced a significant effect although the effect of higher dosages seemed to be longer lasting. After fertilization also nitrogen gave significant increase in growth. The number of seedlings damaged by elk increased the most on N-fertilized plots. Also, phosphorus increased the occurrence of elk damage, but effect seemed to be related to the better growth and more suitable size of P-fertilized seedlings. The effect of potassium on seedling growth and on occurrence of elk damage was negligible.

The PDF includes a summary in English.

  • Laine, E-mail: jl@mm.unknown (email)
  • Mannerkoski, E-mail: hm@mm.unknown
article id 7597, category Article
Aarne Nyyssönen, Kari Mielikäinen. (1978). Metsikön kasvun arviointi. Acta Forestalia Fennica no. 163 article id 7597. https://doi.org/10.14214/aff.7597
English title: Estimation of stand increment.
Original keywords: kuusi; mänty; tilavuuskasvu; metsänmittaus; metsikön kasvu
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; volume increment percentage; increment of stands
Abstract | View details | Full text in PDF | Author Info

The paper concerns the estimation of the increment of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands in the southern half of Finland. For the methods based on stand tables, tree functions forecasting the annual increment of diameter and height during the next 5-year period are presented. The main results of the study, however, are the functions for the volume increment percentage of pine and spruce stands. The independent variables are: forest site type, tree species, stand age and volume, and mean diameter. The standard error of estimate is about 17% in the best functions. Calculations were made also with regard to the application of the results in growth estimation of large forest areas.

The PDF includes a summary in English.

  • Nyyssönen, E-mail: an@mm.unknown (email)
  • Mielikäinen, E-mail: km@mm.unknown
article id 7595, category Article
Erkki Hallman, Pertti Hari, Pentti K. Räsänen, Heikki Smolander. (1978). Effect of planting shock on the transpiration, photosynthesis, and height increment of Scots pine seedlings. Acta Forestalia Fennica no. 161 article id 7595. https://doi.org/10.14214/aff.7595
Keywords: Pinus sylvestris; photosynthesis; Scots pine; planting; stress; seedlings; drought; transpiration; water deficit
Abstract | View details | Full text in PDF | Author Info

In the experiment Scots pine (Pinus sylvestris L.) seedlings were transplanted out in the field. The effect of the treatments on gas metabolism and daily height increment were examined. The seedlings were 5-year old Scots pine plants growing in clay pots, covered with plastic bags. Transpiration and photosynthetic rates were monitored with open IRGA measuring system for a few days before being subjected to the treatments and for one month after. In addition, the daily amounts of transpired water and daily height increments were measured. A model for the potential rate of each metabolic process was constructed.

Planting and additional exposure had a strong and rather permanent effect on the self-regulation of the processes. This effect is very similar to that caused by water deficit. Exposure makes the disturbance more pronounced. Transpiration of the transplanted seedlings decreased in a few days after planting to less than half of the potential value and that of the exposed ones decreased to a quarter of the potential value. The daily amounts of photosynthesis decreased to half of the potential value. There was no recovery in photosynthesis during the whole monitoring period of four weeks. There was a slight recovery in transpiration about five weeks after transplanting.

Thus, the treatment probably generated stress conditions throughout the whole growing period, which is characterized by strong self-regulation of photosynthesis and transpiration, thus causing an essential decrease in the total amount of CO2 fixed. The photosynthesis was depressed especially at elevated temperatures after planting, as during water deficit. Planting and additional exposure did not produce any detectable changes in the dependence of the growth rate on temperature or in the effect of self-regulation on height growth. On the other hand, the level of growth was decreased as a result of planting out.

The PDF includes a summary in Finnish.

  • Hallman, E-mail: eh@mm.unknown (email)
  • Hari, E-mail: ph@mm.unknown
  • Räsänen, E-mail: pr@mm.unknown
  • Smolander, E-mail: hs@mm.unknown
article id 7584, category Article
Leo Heikurainen, Jukka Laine. (1976). Lannoituksen, kuivatuksen ja lämpöolojen vaikutus istutus- ja luonnontaimistojen kehitykseen rämeillä. Acta Forestalia Fennica no. 150 article id 7584. https://doi.org/10.14214/aff.7584
English title: Effect of fertilization, drainage and temperature on the development of planted and natural seedlings on pine swamps.
Original keywords: ojitus; mänty; taimet; lannoitus; ojitetut suot; räme; turvekangas; lämpöolot; sarkaväli
English keywords: Pinus sylvestris; fertilization; drained peatlands; Scots pine; temperature; seedlings; ditch spacing
Abstract | View details | Full text in PDF | Author Info

The paper presents some preliminary results of a 10-year-old study the purpose of which is to determine the effect of simultaneous variations in the intensity of drainage and fertilization on the development of planted and natural seedlings on peatlands under various climatic conditions. The development of the Scots pine (Pinus sylvestris L.) seedlings appeared to be better the more intensive the degree of drainage and fertilization used. The increase in the temperature sum had a positive effect on the development of pine seedlings and decreased the mortality rate.

The best growth result was obtained with a 10 m ditch spacing and strong fertilization. As it is difficult to decrease the 10 m ditch spacing for cost reasons, it can be concluded that on such oligotrophic peatlands as were used in this experiment, only an average growth level in the seedling stands can be reached even with the most efficient forest improvement measures. Broadcast fertilization used in the experiment, at least in large doses, increases seedling mortality, as well as the coverage of the ground vegetation, particularly that of cottongrass and fireweed, and also the shrub height, thus increasing competition. It cannot be recommended for afforestation, and today spot fertilization is used. According to this experiment natural seedlings seem once they have recovered after the first years, to grow better than the planted seedlings. This was true especially in the north and in areas, where drainage was not efficient. The height and height growth of the seedlings were to a large extent dependent on the temperature sum.

The PDF includes a summary in English.

  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Laine, E-mail: jl@mm.unknown
article id 7579, category Article
Pekka Kilkki, Markku Siitonen. (1975). Metsikön puuston simulointimenetelmä ja simuloituun aineistoon perustuvien puustotunnusmallien laskenta. Acta Forestalia Fennica no. 145 article id 7579. https://doi.org/10.14214/aff.7579
English title: Simulation of artificial stands and derivation of growing stock models from this material.
Original keywords: puulajit; menetelmät; metsikkö; puusto; simulointi; puustotunnukset
English keywords: Pinus sylvestris; birch; Picea abies; stand characteristics; tree species; growing stock; methods; simulation of stands
Abstract | View details | Full text in PDF | Author Info

The purpose of this study was that of providing a long-term timber production model (Kilkki and Pökkälä 1975) with growing stock models. The paper is divided into two parts; the first is concerned with generation of the stand data through Monte-Carlo simulation. The growing stock of each stand was described by a DBH-height distribution. The necessary information on the relationships between the stand characteristics was derived from sample plots measured in the national forest inventory of Finland. A total of 1,500 Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst), and birch (Betula sp.) stands, each comprising 100 trees were provided by simulation.

In the second part, models predicting the form factor, timber assortment distribution, and value of the growing stock were derived through regression analysis for each species of tree. The predicting variables included the form factor of the basal area median tree, basal area median diameter, and height in the form factor models. In the timber assortment and value models, the only predicting variable was the volume of the basal area median tree. The Matchcurve-technique (Jensen 1973) was employed in derivation of the regression models.

The PDF includes a summary in English.

  • Kilkki, E-mail: pk@mm.unknown (email)
  • Siitonen, E-mail: ms@mm.unknown
article id 7575, category Article
Robert T Brown, Peitsa Mikola. (1974). The influence of fruticose soil lichens upon the mycorrhizae and seedling growth of forest trees. Acta Forestalia Fennica no. 141 article id 7575. https://doi.org/10.14214/aff.7575
Keywords: Pinus sylvestris; Norway spruce; Betula pendula; Picea abies; regeneration; Scots pine; lichens; Cladonia alpestris; Cladonia rangiferina; Cladonia arbuscula; Cladonia pleurota; Cetraria islandica; Stereocaulon paschale; growth inhibition
Abstract | View details | Full text in PDF | Author Info

Water extracts of six common soil lichens, Cladonia alpestris, C. rangiferina, C. arbuscula (sylvatica), C. pleurota, Cetraria islandica, Stereocaulon paschale, inhibited growth of ectomycorrhizae of Pinus sylvestris (L.). Of 17 fungi (12 mycorrhizal) tested, many were inhibited while others were scarcely influenced or even occasionally stimulated by the extracts. Cladonia alpestris extract inhibited most fungi while C. rangiferina showed much less influence.

In pure culture synthesis experiments, 32P uptake of Pinus sylvestris was significantly reduced by C. alpestris extract. Different species of fungi showed widely variant abilities to pick up 32 P. in nursery experiments, much more vigorous growth of P. sylvestris and Picea abies (L.) H. Karst. was obtained on plots without C. alpestris than on paired plots covered with it. Betula verrucosa (B. pendula Roth) showed no difference. Under natural forest conditions, P. sylvestris seedlings grow much more rapidly where C. alpestris had been eliminated by road building or reindeer grazing than do seedlings only one meter distant under undisturbed C. alpestris cover. It is suggested that by properly controlled reindeer grazing, establishment and early growth of P. sylvestris on Cladonia sites can be much enhanced. By the time that C. alpestris could become re-established the pine seedlings would have grown large enough to suffer little from reindeer grazing. This study shows the continuity of the major components of the forest tundra biome – the dependence of pines, mycorrhizae, lichens, and reindeer and their predators (human or otherwise) upon each other for a healthy existence.

The PDF includes a summary in Finnish.

  • Brown, E-mail: rb@mm.unknown (email)
  • Mikola, E-mail: pm@mm.unknown
article id 7573, category Article
Juhani Päivänen. (1974). Nutrient removal from Scots pine canopy on drained peatland by rain. Acta Forestalia Fennica no. 139 article id 7573. https://doi.org/10.14214/aff.7573
Keywords: Pinus sylvestris; fertilization; Scots pine; precipitation; nutrients; peatlands; macronutrients; stem flow
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to assess the contents and quantities of macronutrients reaching the ground with precipitation, stemflow and throughfall in Scots pine (Pinus sylvestris L.) stands growing on drained peatland, one of which was unfertilized and two of which had been fertilized three growing seasons before the measurements were carried out.

According to the results, the quantities of nutrients reaching the ground with precipitation were relatively large as compared, for example, with those removed with the stem wood carried away from the forest in logging. The nutrient most exposed to leaching from the canopy is potassium. Both the content of potassium in rainwater penetrating the canopy and the quantities reaching the ground are highest in stemflow, decreasing when moving from under the tree crowns toward the edge of the crown projection and into openings in the canopy. The results for phosphorus were similar, although not as clear as for potassium.

The contents of NO3-N were smaller in stemflow than in precipitation. The results did not support assumptions according to which nitrate nitrogen is leached from the canopy or is taken up by the canopy from precipitation. In the case both of precipitation and of throughfall and stemflow, the quantities of nitrite nitrogen recorded were smaller than the degree of precision applied in the determinations carried out (0.01 mg/1). The contents of NH4-N were on average higher in stemflow and throughfall than in precipitation.

Fertilizer application (600 kg/ha of N-P2O5-K2O, 14-18-10) increased the contents of potassium in stemflow and throughfall. A slight increase in phosphorus was also observed. Leaching of inorganic nitrogen was not affected by fertilization.

The PDF includes a summary in Finnish.

  • Päivänen, E-mail: jp@mm.unknown (email)
article id 7555, category Article
Paavo Havas. (1971). Injury to pines in the vicinity of a chemical processing plant in Northern Finland. Acta Forestalia Fennica no. 121 article id 7555. https://doi.org/10.14214/aff.7555
Keywords: Pinus sylvestris; Scots pine; toxicity; needle damages; air pollution; fertilizer processing plant
Abstract | View details | Full text in PDF | Author Info

The present investigation shows that injury to pines (Pinus silvestris L.) in the boreal coniferous zone (65 °N) occurs in winter conditions in the vicinity of a fertilizer processing plant, unless they are covered by snow. This kind of injury has multiple causes. Firstly, fertilizer dust discharged from the process operations may reduce the degree of xeromorphism of the needles, which further results in disorders of the water economy. Secondly, along with the wet fertilizer dust the needles absorb toxic substances, especially, fluorides and certain sulphur compounds. The amounts of fluorides, in particular, are large enough to bring about damage. The combined effect of these factors causes trees to die during winters with long periods of intense cold. It seems, therefore, that in the northern conditions pollution may have effects not observable in more southern regions.

The PDF includes a summary in Finnish.

  • Havas, E-mail: ph@mm.unknown (email)
article id 7548, category Article
Leo Heikurainen, Pertti Veijola. (1971). Lannoituksen ja sarkaleveyden vaikutus rämeen uudistumiseen ja taimien kasvuun. Acta Forestalia Fennica no. 114 article id 7548. https://doi.org/10.14214/aff.7548
English title: Effect of fertilization and ditch spacing on regeneration and seedling growth in pine swamps.
Original keywords: mänty; istutus; taimet; lannoitus; turvekankaat; ojitetut suot; taimikuolleisuus; räme
English keywords: Pinus sylvestris; drained peatlands; Scots pine; planting; mortality; seedlings; fertilizing; pine bogs
Abstract | View details | Full text in PDF | Author Info

In 1965 and 1966 a total of 25 experiments were laid out in various parts of Finland in order to find out the effect of simultaneous variation in the intensity of drainage and fertilization on the development of plantations and natural seedling stands of Scots pine (Pinus sylvestris L.) growing on pine swamps. The fertilizer used was Y fertilizer for peat soils, a fertilizer mixture containing 14 % N, 18 % P2O5 and 10 % K2O. It was applied in rates of 500, 1,000 and 1,500 kg/ha. The ditch spacings studied were 10, 20 and 30 m. The present paper is a preliminary report on a series of studies, the experiments will be observation for a total of 15–20 years.

Mortality of the planted seedlings was found to be the higher after the first growing season, the larger the quantity of fertilizer that had been applied. Fertilizing caused an increase in seedling mortality even after the first growing season following application. At the end of the fifth growing season the height of both natural and planted seedlings is the greater, the larger the quantity of fertilizer that has been applied. Analysis of the height growth of the seedlings showed that larger quantities of fertilizer did not increase growth in the same proportion. The occurrence of growth disturbances is the greater, the more fertilizer has been applied.

Fertilization also changed the composition of ground vegetation. The in the beginning of the experiment  birch (Betula sp.) was absent in the area, but was found in the stands the greater abundance the higher application of the fertilizer.

From the viewpoint of growth of the seedlings the best results were obtained with the greatest intensity of fertilization and the narrowest ditch spacing used in the study. The results also show that strong fertilization and a high degree of drainage intensity are not capable of bringing about any particularly good growth on peatlands which originally are relatively poor in nutrients. The growth values now obtained equal only one third of those obtained on peat soils of greater fertility.

The PDF includes a summary in English.

  • Heikurainen, E-mail: lh@mm.unknown (email)
  • Veijola, E-mail: pv@mm.unknown
article id 7546, category Article
Pentti K. Räsänen. (1970). Nostoajankohdan, pakkaustavan, varastointiajan pituuden ja kastelun vaikutuksesta männyn taimien kehitykseen. Acta Forestalia Fennica no. 112 article id 7546. https://doi.org/10.14214/aff.7546
English title: The effect of lifting date, packing, storing and watering on the field survival and growth of Scots pine seedlings.
Original keywords: mänty; taimet; varastointi; kuolleisuus; kastelu; nostoaika
English keywords: Pinus sylvestris; Scots pine; planting; mortality; storage; seedlings; watering; lifting time
Abstract | View details | Full text in PDF | Author Info

This study was carried out in 1966 in the nursery at Hyytiälä, Korkeakoski Forest District, in Southern Finland. The influence of lifting date (two liftings), way of packing (two methods) and length of storage (one, three and six weeks) on the development of Scots pine (Pinus sylvestris L.), 2 + 1, during the four years following planting was assessed. On the seedlings stored for six weeks, the influence of compensating for the water deficit was also studied.

According to the results, the lifting carried out later, i.e. when the seedlings had already started growth, gave slightly better results than when seedlings were lifted earlier. No difference could be observed for seedlings stored for one week, but for the seedlings stored for three or six weeks, mortality in the lot lifted earlier was 6- to 7-fold that of the seedlings lifted later. The main reason for this was probably that the seedlings of the earlier lifting suffered from lack of water at the time of lifting.

The growth of the seedlings lifted earlier and stored for three weeks showed a decrease compared to those lifted later. For the seedlings stored for six weeks, on the other hand, faster growth was recorded for both the seedlings of the earlier and the later lifting in comparison with those stored for shorter times. Watering increased to some extent the growth of the seedlings stored for six weeks.

During the normal, one- and three-week storing periods, seedlings were well preserved when packed both in bundles and in polythene sacks. Three years after the planting the average mortality was about 10%. Effect of watering was large for those seedlings that had been longer in the storage.

The PDF includes a summary in English.

  • Räsänen, E-mail: pr@mm.unknown (email)
article id 7612, category Article
Timo Kurkela. (1969). Antagonism of healthy and diseased Ericaceous plants to snow blight on Scots pine. Acta Forestalia Fennica no. 101 article id 7612. https://doi.org/10.14214/aff.7612
Keywords: Pinus sylvestris; antagonism; Scots pine; Vaccinium vitis-idaea; pathogens; Calluna vulgaris; control; snow blight; Phacidium infestans; ericaceous evergreens
Abstract | View details | Full text in PDF | Author Info

Two experiments were conducted in Punkaharju and Leivonmäki in the Central Finland in 1966-67 where the spread of the snow blight caused by Phacidium infestans Karst. was investigated in rows of excised branches from a ten-year-old stand of Scots pine (Pinus sylvestris L.). Ericaceous plants (Calluna vulgaris (L.) Hull and Vaccinium vitis-idaea L.) infected with snow moulds were used to determine their influence on the spread of snow blight.

The results show that significant inhibition of snow blight in Scots pine can be achieved with foliage of ericaceous evergreens. The mechanism of this inhibition is an object of conjecture. In healthy ericaceous vegetation it might be caused by saprophytic fungi living on surface of plants or by some constituent of the foliage. In the case of dead ericaceous foliage, the cause of inhibition seems to be the antagonism of other snow moulds. The antagonism of certain saprophytic organism is well known.

The observed inhibition suggests that ericaceous vegetation may be helpful for reforestation by offering a natural control of snow blight, when seedlings of Scots pine do not stand above the surrounding vegetation.

The PDF includes a summary in Finnish.

  • Kurkela, E-mail: tk@mm.unknown (email)
article id 7602, category Article
P. M. A. Tigerstedt. (1969). Progeny tests in a Pinus silvestris (L) seed orchard in Finland. Acta Forestalia Fennica no. 99 article id 7602. https://doi.org/10.14214/aff.7602
Keywords: Pinus sylvestris; Scots pine; heritability; seedlings; progeny
Abstract | View details | Full text in PDF | Author Info

Heritability of first and second-year height growth of Pinus sylvestris (L.) plants was studied using three different mating designs. Plants grew in a plastic greenhouse during the first growth period. During the second growth period they were exposed to open air conditions.

Heritability values varied from zero to 42%. An average heritability based on six separate calculations (two from each mating design) was computed and its reliability was discussed. This heritability value was 18%.

Different ways of improving heritability estimates was discussed and the need of more investigations on trait quality in relation to fitness and on the effect of natural selection and population strategy was emphasized.

  • Tigerstedt, E-mail: pt@mm.unknown (email)
article id 7611, category Article
Kustaa Seppälä. (1969). Kuusen ja männyn kasvun kehitys ojitetuilla turvemailla. Acta Forestalia Fennica no. 93 article id 7611. https://doi.org/10.14214/aff.7611
English title: Post-drainage growth rate of Norway spruce and Scots pine on peat.
Original keywords: kuusi; mänty; kasvu; läpimitan kasvu; turvekankaat; ojitetut suot; pituuskasvu; kasvun elpyminen
English keywords: Pinus sylvestris; Norway spruce; Picea abies; drained peatlands; Scots pine; height growth; growth; diameter growth; revival
Abstract | View details | Full text in PDF | Author Info

The present study is an attempt to establish the response to drainage of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) on some peatland sites, and to determine the revival of the trees and continuance of the growth after drainage. Growth of trees in four types of peatland types of drained peatlands drained between 1908-1918 were studied, and the results were compared with corresponding mineral soil sites

In pine the response to drainage was faster than in spruce in all age classes. Even the oldest groups of trees showed as good growth as trees of the same size growing on mineral soils. The rapidity of revival and the radial growth maximum are affected by the age of the tree at the time of ditching and the site fertility. The size of the trees, too, is of importance for the magnitude of post-drainage radial growth; the influence is similar in different sites. The basal area growth of trees growing on peat usually showed an unbroken increase during the entire post-drainage period. Neither the height growth indicates a decline in growth over time.

In the light of the results from sample tree analysis, it seems that tree growth gradually rises even after the revival period in peatlands originally covered by forest. The are some errors in the comparisons made, but it can be observed that aging of drainage areas as such does not mean that growth conditions become poorer.

The PDF includes a summary in English.

  • Seppälä, E-mail: ks@mm.unknown (email)
article id 7610, category Article
Matti Leikola. (1969). The influence of environmental factors on the diameter growth of forest trees : Auxanometric study. Acta Forestalia Fennica no. 92 article id 7610. https://doi.org/10.14214/aff.7610
Keywords: Pinus sylvestris; Norway spruce; birch; Picea abies; Scots pine; temperature sum; environmental factors; temperature; diameter increment; Betula sp.; xylem; daily increment
Abstract | View details | Full text in PDF | Author Info

The influence of various environmental factors on the diameter growth of trees has been studied based on data collected by following daily increment of trees and various environmental factors during the growing season in 1964–1967. The field work was carried out in two experimental stands, a Scots pine (Pinus sylvestris L.) stand and a mixed stands growing birch (Betula sp.), Norway spruce (Picea abies (L.) H. Karst.) and Scots pine, in Southern Finland.

The results show that the temperature sums preceding the beginning of diameter growth were of the same magnitude in the years studied, which indicates dependence in the relationship. Formation of new xylem cells took place in the pine stem ca. every third day when the diameter growth was most active. No summer growth inhibition was detected in diameter growth.

None of the cumulative temperature sums tried determined the time of cessation of diameter growth. In several cases, positive correlation was found between the length of the growing season and the width of the annual ring formed. When studying the relationships between the diameter increment and the environmental factors, it was found that diameter increment was totally masked in the records by the hydrostatic changes in the stem. Relationships between the diameter increment and the environmental factors of the second day preceding growth were found to be poor. In studying the deviations of the recorded daily increments from the regression surface, no clear general trend was seen for pine and spruce, but clear diminishing trend toward the end og the growing season could be seen for birch in 1967.

  • Leikola, E-mail: ml@mm.unknown (email)
article id 7188, category Article
Paavo Yli-Vakkuri, Pentti K. Räsänen, Asko Hilli. (1968). Taimien talvivarastoinnista ja sen vaikutuksesta männyn taimien istutuskelpoisuuteen. Acta Forestalia Fennica no. 88 article id 7188. https://doi.org/10.14214/aff.7188
English title: Cold-storage and its effects on the field survival and growth of planted Scots pine.
Original keywords: mänty; taimitarha; taimikasvatus; taimet; kylmävarasto; talvivarastointi; taimiviljely
English keywords: Pinus sylvestris; nursery; Scots pine; seedlings; cold storage; winterstorage
Abstract | View details | Full text in PDF | Author Info

The aim of this study was to find out the planting vigour of Scots pine (Pinus sylvestris L.) stored over the winter either in winter storage mainly in the temperature of 4 – -6 °C or in nursery beds. The experimental planting included about 4,500 of 2+1 transplants in Northern Finland. In spring 1965 the control plants were lifted in the spring before budbreak and stored in closed bags in a cold store, in the following year the control plants were lifted in June when the growth had started.

Winter storage of pine transplants in a cold store, tightly closed into bags for the major period, did not, according to the results, increase plant mortality as compared to lifting in the spring. Soaking the stored-plant roots did not affect plant mortality. Mortality was rather small in all treated lots and probably more dependent on planting site and other local factors.

No consistent difference on the leader growth, needle length, bud number and plant grade was found between the plants stored over winter and those lifted in the spring. Sealing the plants into tight bags for winter proved to be suitable method, efficiently preventing water shortage in the plants. No moulds or fungal diseases were found in the plants. In the exceptionally cold 1965–1966 winter, temperature in the cold store sank to -15 °C, but in spite of the temperatures below the recommended storing temperature, the plants survived well. The reason was that the plants froze slowly in the fall and thawed out slowly in the spring.

The value of vigour grade in predicting plant-characteristic development proved to be good, and predicted plant development also in the following year fairly well.

The PDF includes a summary in English.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
  • Räsänen, E-mail: pr@mm.unknown
  • Hilli, E-mail: ah@mm.unknown

Category : Research article

article id 22013, category Research article
Bodil Häggström, Reimo Lutter, Tomas Lundmark, Fredrik Sjödin, Annika Nordin. (2023). Effect of arginine-phosphate addition on early survival and growth of Scots pine, Norway spruce and silver birch. Silva Fennica vol. 57 no. 2 article id 22013. https://doi.org/10.14214/sf.22013
Keywords: Pinus sylvestris; Betula pendula; Picea abies; forest regeneration; seedling growth; seedling survival; arginine
Highlights: Arginine-phosphate addition (APA) represents a potential tool to aid regeneration of planted trees, especially to increase survival of Scots pine seedlings on sites where susceptible to pests;Effects of APA however varies between different sites.
Abstract | Full text in HTML | Full text in PDF | Author Info
Applying arginine-phosphate (AP) to tree seedlings at planting is a novel silvicultural practice in Northern Europe to improve the success of forest regeneration. We present three case-studies of the potential advantages of adding AP at planting on the establishment and damage susceptibility of seedlings in pure and mixed plantings of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst. ) and silver birch (Betula pendula Roth) over two years in the field. Location of study sites were in southern (S), northeastern (NE) and northwestern (NW) Sweden. The main agents of damage were pine weevil (Hylobius abietis L.) on conifers at the south site, browsing of birch at all sites and browsing/other top damage to conifers at the north sites. The effect of adding AP varied between the sites. It was positive for survival of pine at site S, despite considerable damage by pine weevil. However, at the S site more of the surviving spruce and birch were browsed when treated with AP. At the NE site AP-treatment had positive effects on conifer growth. At the NW site adding AP positively affected survival and growth of all three species, and AP-treated seedlings of all species were less browsed than untreated seedlings. AP treatment presents a potential tool to improve the success of forest regeneration, especially when establishing pine stands in south Sweden.
  • Häggström, Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden ORCID https://orcid.org/0000-0002-7738-5493 E-mail: bodil.haggstrom@slu.se
  • Lutter, Institute of Forestry and Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, Tartu 51006, Estonia ORCID https://orcid.org/0000-0001-5847-4282 E-mail: reimo.lutter@emu.ee
  • Lundmark, Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden ORCID https://orcid.org/0000-0003-2271-3469 E-mail: tomas.lundmark@slu.se
  • Sjödin, Unit for field-based forest research, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden E-mail: fredrik.sjodin@slu.se
  • Nordin, Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden ORCID https://orcid.org/0000-0002-5765-3550 E-mail: annika.nordin@slu.se
article id 10769, category Research article
Harri Mäkinen, Pekka Nöjd, Samuli Helama. (2022). Recent unexpected decline of forest growth in North Finland: examining tree-ring, climatic and reproduction data. Silva Fennica vol. 56 no. 4 article id 10769. https://doi.org/10.14214/sf.10769
Keywords: Pinus sylvestris; Picea abies; precipitation; temperature; seed production; tree-ring width; growth variation
Highlights: Tree-ring indices of Scots pine showed decadal variations and a prolonged reduction both on mineral soil sites and peatlands after the mid 2000s; The indices of Norway spruce had less pronounced decadal variations and no trend-like reduction over the last 15 years; Temperature and drought explain some part of the observed growth variability.
Abstract | Full text in HTML | Full text in PDF | Author Info

After a decades-long increasing trend, the recent results of the National Forest Inventory (NFI) reported a decline of forest growth in North Finland. The aim of this study was to assess climatic and reproduction influences behind the growth decline. We used tree-ring data that had been collected by NFI using systematic sampling. The tree-ring width series were detrended using the regional curve standardisation (RCS) removing age-related trends. The resulting tree-ring indices of Scots pine (Pinus sylvestris L.) showed decadal variations with low increment in the 1990s, and high increment in the 1980s and the early years of the current century. Thereafter, a prolonged growth reduction for pine started both on the mineral soil sites and peatlands. The tree-ring indices of Norway spruce (Picea abies (L.) Karst.) had less pronounced decadal variations and no trend-like reduction over the last 15 years. High spring and summer temperatures were found to enhance radial growth, but high winter temperatures were related to low growth for pine and spruce in the following summer. Temperature variation, accompanied by variables indicating years of drought and intensive flowering, accounted for 34% annual growth variance of pine and 21–44% for spruce. Thus, the results imply that climatic factors may have to some extent contributed to the recent growth reduction of pine. Due to its ecological and economic consequences growth decline needs to be further monitored and investigated. Moreover, analyses of stand and age structure, potentially affecting the growth decline, were beyond the scope of this paper, but also warrant further investigation.

  • Mäkinen, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, 00790 Helsinki ORCID https://orcid.org/0000-0002-1820-6264 E-mail: harri.makinen@luke.fi (email)
  • Nöjd, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, 00790 Helsinki E-mail: pekka.nojd@luke.fi
  • Helama, Natural Resources Institute Finland (Luke), Ounasjoentie 6, 96200 Rovaniemi, Finland ORCID https://orcid.org/0000-0002-9777-3354 E-mail: samuli.helama@luke.fi
article id 10707, category Research article
Martin Goude, Urban Nilsson, Euan Mason, Giulia Vico. (2022). Comparing basal area growth models for Norway spruce and Scots pine dominated stands. Silva Fennica vol. 56 no. 2 article id 10707. https://doi.org/10.14214/sf.10707
Keywords: Pinus sylvestris; basal area; Picea abies; National Forest Inventory; regression; difference equation; long-term experiment
Highlights: Models were developed that predict basal area growth for Scot pine and Norway spruce stands in Sweden; There were no apparent differences in the ability to predict basal area development between a linear regression model for basal area growth or a compatible growth and yields model for basal area; The model based on data from the 80s had similar performance as the models with data from the 2000s, showing that both can reliably be used to predict forest development.
Abstract | Full text in HTML | Full text in PDF | Author Info

Models that predict forest development are essential for sustainable forest management. Constructing growth models via regression analysis or fitting a family of sigmoid equations to construct compatible growth and yield models are two ways these models can be developed. In this study, four species-specific models were developed and compared. A compatible growth and yield stand basal area model and a five-year stand basal area growth model were developed for Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.). The models were developed using data from permanent inventory plots from the Swedish national forest inventory and long-term experiments. The species-specific models were compared, using independent data from long-term experiments, with a stand basal area growth model currently used in the Swedish forest planning system Heureka (Elfving model). All new models had a good, relatively unbiased fit. There were no apparent differences between the models in their ability to predict basal area development, except for the slightly worse predictions for the Norway spruce growth model. The lack of difference in the model comparison showed that despite the simplicity of the compatible growth and yield models, these models could be recommended, especially when data availability is limited. Also, despite using more and newer data for model development in this study, the currently used Elfving model was equally good at predicting basal area. The lack of model difference indicate that future studies should instead focus on model development for heterogeneous forests which are common but lack in growth and yield modelling research.

  • Goude, Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, SE-230 53 Alnarp, Sweden ORCID https://orcid.org/0000-0002-2179-292X E-mail: martin.goude@slu.se (email)
  • Nilsson, Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, SE-230 53 Alnarp, Sweden E-mail: urban.nilsson@slu.se
  • Mason, School of Forestry, University of Canterbury, Private Bag 4800, Christchurch, New Zealand E-mail: euan.mason@canterbury.ac.nz
  • Vico, Department of Crop Production Ecology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden E-mail: giulia.vico@slu.se
article id 10627, category Research article
Christian Kuehne, J. Paul McLean, Kobra Maleki, Clara Antón-Fernández, Rasmus Astrup. (2022). A stand-level growth and yield model for thinned and unthinned even-aged Scots pine forests in Norway. Silva Fennica vol. 56 no. 1 article id 10627. https://doi.org/10.14214/sf.10627
Keywords: Pinus sylvestris; mortality; volume growth; seemingly unrelated regression; production forestry; system of equations
Highlights: The presented growth and yield model consists of component equations for dominant height, stem density, total basal area, and total stem volume; The component equations were fitted simultaneously using seemingly unrelated regression; The model is capable to forecast and compare outcomes of varying thinning regimes; The new component equations better represent the improved growing conditions for Scots pine in Norway.
Abstract | Full text in HTML | Full text in PDF | Author Info

Management of Scots pine (Pinus sylvestris L.) in Norway requires a forest growth and yield model suitable for describing stand dynamics of even-aged forests under contemporary climatic conditions with and without the effects of silvicultural thinning. A system of equations forming such a stand-level growth and yield model fitted to long-term experimental data is presented here. The growth and yield model consists of component equations for (i) dominant height, (ii) stem density (number of stems per hectare), (iii) total basal area, (iv) and total stem volume fitted simultaneously using seemingly unrelated regression. The component equations for stem density, basal area, and volume include a thinning modifier to forecast stand dynamics in thinned stands. It was shown that thinning significantly increased basal area and volume growth while reducing competition related mortality. No significant effect of thinning was found on dominant height. Model examination by means of various fit statistics indicated no obvious bias and improvement in prediction accuracy in comparison to existing models in general. An application of the developed stand-level model comparing different management scenarios exhibited plausible long-term behavior and we propose this is therefore suitable for national deployment.

  • Kuehne, Norwegian Institute of Bioeconomy Research, Division of Forestry and Forest Resources, P.O. Box 115, NO-1431 Ås, Norway E-mail: christian.kuehne@nibio.no (email)
  • McLean, Norwegian Institute of Bioeconomy Research, Division of Forestry and Forest Resources, P.O. Box 115, NO-1431 Ås, Norway E-mail: paul.mclean@nibio.no
  • Maleki, Norwegian Institute of Bioeconomy Research, Division of Forestry and Forest Resources, P.O. Box 115, NO-1431 Ås, Norway E-mail: kobra.maleki@nibio.no
  • Antón-Fernández, Norwegian Institute of Bioeconomy Research, Division of Forestry and Forest Resources, P.O. Box 115, NO-1431 Ås, Norway E-mail: clara.anton.fernandez@nibio.no
  • Astrup, Norwegian Institute of Bioeconomy Research, Division of Forestry and Forest Resources, P.O. Box 115, NO-1431 Ås, Norway E-mail: rasmus.astrup@nibio.no
article id 10534, category Research article
Matti Haapanen, Seppo Ruotsalainen. (2021). Adaptive performance of genetically improved and unimproved seedlings of Scots pine. Silva Fennica vol. 55 no. 5 article id 10534. https://doi.org/10.14214/sf.10534
Keywords: Pinus sylvestris; cold hardiness; growth rhythm; seed orchards; bud set; freezing test; reproductive materials
Highlights: We studied the variation in adaptive traits in one-year-old seedlings of Scots pine representing different levels of genetic gain and geographical origins; All the adaptive traits analyzed showed clinal co-variation with the latitude of origin; Differences in adaptive performance between genetically improved and unimproved reproductive materials were mostly small and insignificant when the effect of the latitudinal origin was considered; First-generation seed orchard materials implied slightly poorer autumn frost hardiness compared to other materials, but the results were ambiguous.
Abstract | Full text in HTML | Full text in PDF | Author Info

Our main objective was to determine whether various genetically improved reproductive materials of Scots pine (Pinus sylvestris L.) differ in growth rhythm, autumn cold acclimation and resilience from unimproved materials. The study consisted of two successive indoor experiments with Scots pine seedlings representing four levels of genetic gain (unimproved natural stands, first-generation seed orchards, 1.5-generation seed orchards and seed orchards established with freezing-tested parents) and a wide range of geographical origins within Finland. The seedlings were assessed for terminal shoot elongation, growth cessation, bud set, freezing injuries and bud flushing over the first growth period. All the adaptive traits showed a latitudinal trend regardless of the genetic level. Seed orchard progenies and natural stand progenies did not differ significantly in the timing of growth cessation, bud set, and the flushing rate of the frost-injured seedlings, after the trait variation was adjusted to the latitude of origin. The differences in autumn frost hardiness were insignificant, too, except for the somewhat higher injury rate displayed by the first-generation seed orchard materials. The finding was not conclusive due to ambiguous results from the two experiments. Overall, we did not find evidence of alarming compromises in the adaptive performance of genetically improved materials.

  • Haapanen, Natural Resources Institute Finland (Luke), Production systems, Latokartanonkaari 9, FI-00790 Helsinki, Finland ORCID https://orcid.org/0000-0003-3294-501X E-mail: matti.haapanen@luke.fi (email)
  • Ruotsalainen, Natural Resources Institute Finland (Luke), Production systems, Vipusenkuja 5, FI-57200 Savonlinna, Finland ORCID https://orcid.org/0000-0002-2547-0282 E-mail: seppo.ruotsalainen@luke.fi
article id 10494, category Research article
Hannu Hökkä, Ari Laurén, Leena Stenberg, Samuli Launiainen, Kersti Leppä, Mika Nieminen. (2021). Defining guidelines for ditch depth in drained Scots pine dominated peatland forests. Silva Fennica vol. 55 no. 3 article id 10494. https://doi.org/10.14214/sf.10494
Keywords: Pinus sylvestris; forest management; peatland; drainage; ditch network maintenance; process model; water table
Highlights: Process-based hydrological model was applied to drained peatland forests representing a wide range of conditions in Finland; Ditch depth keeping the median July–August water table below 0.35 m was defined; Ditch depth depended on climatic conditions, stand volume, peat properties, and ditch spacing; Shallower ditches than recommended in practice proved to be sufficient in most situations.
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We used a process-based hydrological model SUSI to improve guidelines for ditch network maintenance (DNM) operations on drained peatland forests. SUSI takes daily weather data, ditch depth, strip width, peat properties, and forest stand characteristics as input and calculates daily water table depth (WTD) at different distances from ditch. The study focuses on Scots pine (Pinus sylvestris L.) dominated stands which are the most common subjects of DNM. Based on a literature survey, and consideration of the tradeoffs between forest growth and detrimental environmental impacts, long term median July–August WTD of 0.35 m was chosen as a target WTD. The results showed that ditch depths required to reach such WTD depends strongly on climatic locations, stand volume, ditch spacing, and peat thickness and type. In typical ditch cleaning areas in Finland with parallel ditches placed about 40 m apart and tree stand volumes exceeding 45 m3 ha–1, 0.3–0.8 m deep ditches were generally sufficient to lower WTD to the targeted depth of 0.35 m. These are significantly shallower ditch depths than generally recommended in operational forestry. The main collector ditch should be naturally somewhat deeper to permit water outflow. Our study brings a firmer basis on environmentally sound forestry on drained peatlands.

  • Hökkä, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: hannu.hokka@luke.fi (email)
  • Laurén, University of Eastern Finland, Faculty of Science and Forestry, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ari.lauren@uef.fi
  • Stenberg, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: leena.stenberg@luke.fi
  • Launiainen, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: samuli.launiainen@luke.fi
  • Leppä, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: kersti.leppa@luke.fi
  • Nieminen, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, P.O. Box 2, FI-00791 Helsinki, Finland E-mail: mika.nieminen@luke.fi
article id 10420, category Research article
Eeva-Liisa Terhonen, Jumoke Babalola, Risto Kasanen, Risto Jalkanen, Kathrin Blumenstein. (2021). Sphaeropsis sapinea found as symptomless endophyte in Finland. Silva Fennica vol. 55 no. 1 article id 10420. https://doi.org/10.14214/sf.10420
Keywords: Pinus sylvestris; Scots pine; Diplodia sapinea; Diplodia tip blight
Highlights: Sphaeropsis sapinea was found for the first time as an endophyte in healthy Scots pine in Finland; This finding confirms that S. sapinea can proliferate in a symptomless stage in Scots pine in Finland.
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The aim of this study was to determine if the ascomycete fungus Sphaeropsis sapinea (Fr.) Dyko & B. Sutton (syn. Diplodia sapinea (Fr.) Fuckel) could be cultured from surface sterilized Scots pine twigs presenting the endophytic stage of this fungus. This fungus causes the disease called Diplodia tip blight in conifers. Symptoms become visible when trees have been weakened by abiotic stressors related to temperature, drought and hailstorms. The disease is rapidly increasing and is observed regularly in Scots pine (Pinus sylvestris L.) forests in Europe. Changes in climatic conditions will gradually increase the damage of this pathogen, because it is favored by elevated temperatures and additionally the host trees will be more susceptible due to related environmental stress. Diplodia tip blight is emerging towards Northern latitudes, thus, actions to monitor the spread of S. sapinea in pine-dominated forests should be undertaken in Finland. Our aim was to search for S. sapinea in Scots pine along a transect in Finland. Branch samples were collected from healthy Scots pine, fungal endophytes were isolated and morphologically identified. Sixteen S. sapinea strains were found from four Scots pine trees from two locations. This finding confirms that S. sapinea is found as an endophyte in healthy Scots pine in Finland.

  • Terhonen, Forest Pathology Research Group, Department of Forest Botany and Tree Physiology, Faculty of Forest Sciences and Forest Ecology, University of Goettingen, Büsgen-Institute, Büsgenweg 2, D-37077 Göttingen, Germany E-mail: terhonen@uni-goettingen.de (email)
  • Babalola, Forest Pathology Research Group, Department of Forest Botany and Tree Physiology, Faculty of Forest Sciences and Forest Ecology, University of Goettingen, Büsgen-Institute, Büsgenweg 2, D-37077 Göttingen, Germany E-mail: j.babalola@stud.uni-goettingen.de
  • Kasanen, Forest Pathology Lab, Department of Forest Sciences, University of Helsinki, Latokartanonkaari 7, FI-00014 University of Helsinki, Finland E-mail: risto.kasanen@helsinki.fi
  • Jalkanen, Rovaniemi Research Unit, Natural Resources Institute Finland (Luke), Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: ristjal@gmail.com
  • Blumenstein, Forest Pathology Research Group, Department of Forest Botany and Tree Physiology, Faculty of Forest Sciences and Forest Ecology, University of Goettingen, Büsgen-Institute, Büsgenweg 2, D-37077 Göttingen, Germany E-mail: kathrin.blumenstein@uni-goettingen.de
article id 10276, category Research article
Adas Marčiulynas, Vaida Sirgedaitė-Šėžienė, Povilas Žemaitis, Āris Jansons, Virgilijus Baliuckas. (2020). Resistance of Scots pine half-sib families to Heterobasidion annosum in progeny field trials. Silva Fennica vol. 54 no. 4 article id 10276. https://doi.org/10.14214/sf.10276
Keywords: Pinus sylvestris; field trials; half-sib families; root rot pathogen; total phenolic compounds; tree susceptibility
Highlights: Large genetic variation was estimated in the resistance of Scots pine half-sib families to root rot in field trials; A strong relationship was observed between family resistance to root rot and phenolic compound concentration in the wood.
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Five Scots pine (Pinus sylvestris L.) progeny field trials, each established in different Lithuanian regions of provenance in 1983, were studied. Each progeny field trial consists of 140 half-sib families from seven populations (20 families from each population). The evaluation was carried out in 2012 and 2018 to assess the families resistance to Heterobasidion annosum (Fr.) Bref. An index of resistance in the infected plots was calculated. To verify the accuracy of the method, total phenolic compounds (TPC) was chosen as key parameter to compare with the plant resistance index. During the six years between the two assessments, the percentage of living Scots pine trees in the progeny field trials decreased up to 20 percentage points (range: 4 p.p. to 20 p.p.). In 2018 the area of H. annosum damaged plots (in percentage from total field trial area) varied from 17 to 27%. Tree mortality in the trial correlates with site soil fertility – more fertile soils were distinguished by higher tree percentage loss and vice versa. Using analysis from combined data of all progeny trials, the family variance component reached 13.3 ± 2.2% and family heritability was 0.81. Family heritability estimates for root rot resistance show possibilities of high breeding effectiveness. The correlations between the trials in family resistance estimates were negligible (ranging from 0 to 0.28). The significant high correlation coefficient was determined between the resistance index and TPC concentration (r = 0.77, p = 0.0003). This allows us to assume that plant resistance is directly linked on TPC synthesis. The results indicate that the chosen methods of chemical resistance for identification of root rot-resistant genotypes are applicable for the selection of Scots pine half-sib families in the field trials with higher resistance to pathogens.

  • Marčiulynas, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: adas.marciulynas@mi.lt (email)
  • Sirgedaitė-Šėžienė, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: vaida.seziene@mi.lt
  • Žemaitis, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: povilas.zemaitis@mi.lt
  • Jansons, Latvian State Forest Research Institute “Silava”, Department of Forest Tree Breeding, Rigas St.t. 111, Salaspils LV-2169, Latvia E-mail: aris.jansons@silava.lv
  • Baliuckas, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: virgilijus.baliuckas@mi.lt
article id 10389, category Research article
Juho Matala, Harri Kilpeläinen, Henrik Heräjärvi, Tapio Wall, Erkki Verkasalo. (2020). Sawlog quality and tree dimensions of Scots pine 34 years after artificial moose browsing damage. Silva Fennica vol. 54 no. 3 article id 10389. https://doi.org/10.14214/sf.10389
Keywords: Pinus sylvestris; growth; timber quality; Alces alces; defect
Highlights: The first controlled, long-term, experimental study on the tree dimensions and sawlog quality after moose damage; The trees damaged at the seedling stage had a smaller diameter, height, and tree volume at the end of the experiment; The heavier the clipping treatment, the more likely the stem form deteriorated; Deteriorated stem form and vertical branches were the most typical defects.
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Moose (Alces alces L.) browsing causes severe damage in Scots pine (Pinus sylvestris L.) seedling stands. The effects of this damage on the quality of sawlogs were studied in a long-term controlled experiment. This article reports the stem size and external quality characteristics of Scots pine stems 34 years after artificial moose browsing damage. Damaging the trees by clipping the main stem at the seedling stage reduced the diameter, height, and tree volume of the trees at the end of the experiment. The tree growth reduction was dependent on the severity of clipping. The differences between the damaged and the control trees were more obvious in diameter than in height at the time of final felling. Stem form defects and vertical branches were the most typical externally detectable defects caused by clipping. Defects in the butt logs were detected in 71–89% of the damaged trees, depending on the clipping treatment severity. The stronger the clipping treatment, the more likely the stem form was defected and the more commonly were vertical branches and crooks detected in the stems. The results indicate that both tree dimensions and stem quality suffer from moose browsing. The findings of this controlled experiment more likely underestimate than overestimate the damage in comparison to real moose browsing. Further analyses are required to assess the effects of browsing damage on the internal quality of sawlogs and subsequent economic outcomes.

  • Matala, Natural Resources Institute Finland (Luke), Natural resources, Yliopistokatu 6B, FI-80101 Joensuu, Finland E-mail: juho.matala@luke.fi (email)
  • Kilpeläinen, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Yliopistokatu 6B, FI-80101 Joensuu, Finland E-mail: harri.kilpelainen@luke.fi
  • Heräjärvi, Natural Resources Institute Finland (Luke), Production systems, Yliopistokatu 6B, FI-80101 Joensuu, Finland E-mail: henrik.herajarvi@luke.fi
  • Wall, Natural Resources Institute Finland (Luke), Research infrastructure services, Yliopistokatu 6B, FI-80101 Joensuu, Finland E-mail: tapio.wall@luke.fi
  • Verkasalo, Natural Resources Institute Finland (Luke), Production systems, Yliopistokatu 6B, FI-80101 Joensuu, Finland E-mail: erkki.verkasalo@luke.fi
article id 10273, category Research article
Lasse Aro, Anssi Ahtikoski, Jyrki Hytönen. (2020). Profitability of growing Scots pine on cutaway peatlands. Silva Fennica vol. 54 no. 3 article id 10273. https://doi.org/10.14214/sf.10273
Keywords: Pinus sylvestris; afforestation; bare land value; financial performance; peat cutaway area; stand-level optimization
Highlights: The potential wood production on cutaway peatlands can be high; Afforestation with seeding or planting was profitable at 3% rate of interest; In northern Finland, the afforestation method, ditch spacing and fertilization affected the bare land value.
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A major after-use option for former peat harvesting areas has been afforestation. The profitability of afforestation with Scots pine trees (Pinus sylvestris L.) was studied in two 31–32-year old experiments in southern and northern Finland. The stands were established by seeding and planting, and various fertilization treatments and drainage intensities were tested. The financial performance for each plot was assessed in three steps. First, the costs occurred during the measurement time were summed up according to their present value. Then, for the rest of the rotation (i.e., from the age of 31/32 onwards) the stand management was optimized in order to maximize the net present value (MaxNPV). Finally, bare land values (BLVs) were calculated by summing up the present value of costs and the MaxNPV and converting the sum of the series into infinity. The afforestation method did not affect the mean annual increment (MAI; 9.2–9.5 m3 ha–1 a–1) in the southern experiment. In the northern experiment the afforestation method, ditch spacing and fertilization had significant effects on the MAI of the stands. The average MAI of the planted pines was 8.9 m3 ha–1 a–1, and for seeded pines it was 7.5 m3 ha–1 a–1. The BLV at an interest rate of 3% was positive for all stands in both regions. In the northern region afforestation method, ditch spacing and fertilization also had a significant effect on the BLV. When the interest rate was 5%, almost two thirds of the stands had a negative BLV in both regions.

  • Aro, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Itäinen Pitkäkatu 4A, FI-20520 Turku, Finland E-mail: lasse.aro@luke.fi (email)
  • Ahtikoski, Natural Resources Institute Finland (Luke), Natural resources, Paavo Havaksentie 3, FI-90570 Oulu, Finland ORCID https://orcid.org/0000-0003-1658-3813 E-mail: anssi.ahtikoski@luke.fi
  • Hytönen, Natural Resources Institute Finland (Luke), Natural resources, Teknologiakatu 7, FI-67100 Kokkola, Finland ORCID http://orcid.org/0000-0001-8475-3568 E-mail: jyrki.hytonen@luke.fi
article id 10259, category Research article
Jyrki Hytönen, Hannu Hökkä. (2020). Comparison of granulated and loose ash in fertilisation of Scots pine on peatland. Silva Fennica vol. 54 no. 2 article id 10259. https://doi.org/10.14214/sf.10259
Keywords: Pinus sylvestris; wood ash; nutrition; fertilisation; granulation; PK fertiliser
Highlights: Granulated ash and commercial PK fertilizer increased stand growth in similar way during 15-year study period; Loose ash gave stronger and faster response than granulated ash.
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The effects of wood ash fertilisation on tree nutrition and growth on forested peatlands has been studied using loose ash, but in practice, ash fertilisation is done almost exclusively with granulated ash. In this study, the effects of granulated ash and loose ash (both 5 Mg ha–1) on the growth and nutrition of Scots pine (Pinus sylvestris L.) stands were compared between a nitrogen-poor and a nitrogen-rich site over 15 years. On the nitrogen-rich site, wood ash application was also compared with commercial PK fertilisation. On the nitrogen-rich site, mean stand volume growth increase over unfertilised control treatment during the 15 year study period using granulated ash and commercial PK fertiliser was of the same magnitude (on average, 2.2–2.3 m3 ha–1 a–1). However, when loose ash was used growth increase over control was higher (3.7 m3 ha–1 a–1). On the nitrogen-poor site, the mean growth increase gained by loose or granulated ash (1.4–1.5 m3 ha–1 a–1) over the unfertilised control treatment was not significant. Fertilisation with loose ash or PK increased foliar P, K and B concentrations already in the first or second growing season, following fertilisation on both sites. Granulated ash increased foliar P concentrations on the nitrogen-rich site less than loose ash. After an initial increase, foliar P, K and B concentrations decreased at the end of study period. On the nitrogen-poor site, foliar P concentrations were below the deficiency limit by the end of the study period.

  • Hytönen, Natural Resources Institute Finland, Natural Resources, Teknologiakatu 7, FI-67100 Kokkola, Finland ORCID https://orcid.org/0000-0001-8475-3568 E-mail: jyrki.hytonen@luke.fi (email)
  • Hökkä, Natural Resources Institute Finland, Natural Resources, Paavo Havaksentie 3, FI-90570 Oulu, Finland E-mail: hannu.hokka@luke.fi
article id 10243, category Research article
Laura Pikkarainen, Jaana Luoranen, Antti Kilpeläinen, Teppo Oijala, Heli Peltola. (2020). Comparison of planting success in one-year-old spring, summer and autumn plantings of Norway spruce and Scots pine under boreal conditions. Silva Fennica vol. 54 no. 1 article id 10243. https://doi.org/10.14214/sf.10243
Keywords: Pinus sylvestris; Picea abies; seedling damage; forest regeneration; field performance; planting season
Highlights: In Norway spruce, 84% of all plantings were successful, whereas in Scots pine, the corresponding number was 52%; The major reason for poor planting results was poor work quality; An extended planting season is possible for Norway spruce in southern and central Finland; In Scots pine, there are still large uncertainties in the success of summer and autumn plantings.
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In Nordic countries, tree planting of seedlings is mainly performed during spring and early summer. Interest has increased in extending the planting window throughout the unfrozen growing season. This study compared the success of one-year-old spring, summer and autumn plantings in practical forestry in Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) in southern and central Finland. Planting success was based on the number of viable seedlings per hectare relative to a species-specific target density. The influence of different factors to poor planting results were determined, including quality of site preparation and planting, and sources of natural damage. Overall, in Norway spruce, 85, 69 and 84% and in Scots pine 53, 55 and 40% of spring, summer and autumn plantings succeeded. In Norway spruce, the planting results were consistent between the southern and central regions, whereas in Scots pine, the success was slightly lower in the south. The poor work quality and a low density of appropriate planting spots, contributed to poor planting results, regardless of planting season, region or tree species. Considering different damages, especially mammal damage contributed to the failure of Scots pine spring plantings, whereas in summer plantings, corresponding single failure reason could not be identified. Based on our findings, extending the planting season of Norway spruce could be recommended in both regions. For Scots pine, there is still significant uncertainty about the success of summer and autumn plantings, partially due to the limited number of plantings available for analyses.

  • Pikkarainen, School of Forest Sciences, University of Eastern Finland, Yliopistonkatu 7, FI-80100 Joensuu, Finland E-mail: laura.pikkarainen@uef.fi (email)
  • Luoranen, Natural Resources Institute Finland (Luke), Production Systems, Neulaniementie 5, FI-70210 Kuopio, Finland E-mail: jaana.luoranen@luke.fi
  • Kilpeläinen, School of Forest Sciences, University of Eastern Finland, Yliopistonkatu 7, FI-80100 Joensuu, Finland E-mail: antti.kilpelainen@uef.fi
  • Oijala, Metsä Group, Metsä Forest, Kuormaajantie 7, FI-40320 Jyväskylä, Finland E-mail: teppo.oijala@metsagroup.com
  • Peltola, School of Forest Sciences, University of Eastern Finland, Yliopistonkatu 7, FI-80100 Joensuu, Finland E-mail: heli.peltola@uef.fi
article id 10183, category Research article
Tomi Karjalainen, Petteri Packalen, Janne Räty, Matti Maltamo. (2019). Predicting factual sawlog volumes in Scots pine dominated forests using airborne laser scanning data. Silva Fennica vol. 53 no. 4 article id 10183. https://doi.org/10.14214/sf.10183
Keywords: Pinus sylvestris; area based approach; k-NN; sawlog
Highlights: We predicted visually bucked factual sawlog volumes at the 30 × 30 m plot-level with several alternatives; The lowest root mean squared error value of approximately 21% was obtained with a linear mixed-effects model that employed factual sawlog volume as a response variable and airborne laser scanning metrics as predictors; The sawlog reduction model commonly used in Finland performed poorly.
Abstract | Full text in HTML | Full text in PDF | Author Info

The aim in the study was to compare alternatives for the prediction of factual sawlog volumes using airborne laser scanning (ALS) data in Scots pine (Pinus sylvestris L.) dominated forests in eastern Finland. Accurate estimates of factual sawlog volume are desirable to ease the planning of harvesting operations. The factual sawlog volume of pines was derived from visual bucking, i.e. a procedure where the defects were located on each stem during sample plot measurements. For other species, the theoretical sawlog volume was considered also as the factual sawlog volume due to data restrictions. We predicted factual sawlog volume with eight alternatives that were based on either linear mixed-effects models or k-nearest neighbour imputations. An existing sawlog reduction model, commonly used in Finland, was also tested individually and combined with a number of the alternatives, and site type information was also utilised. Model fitting and prediction was implemented at the 15 × 15 m level, but accuracy was assessed at the 30 × 30 m level. The relative root mean squared error (RMSE%) values for the factual sawlog volume predictions varied between 20.9% and 33.5%, and the best accuracy was obtained with a linear mixed-effects model. These results indicate that factual sawlog volumes in Scots pine dominated forests can be predicted with reasonable accuracy with ALS data.

  • Karjalainen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: tomikar@uef.fi (email)
  • Packalen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: petteri.packalen@uef.fi
  • Räty, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: janne.raty@uef.fi
  • Maltamo, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: matti.maltamo@uef.fi
article id 10179, category Research article
Lauri Korhonen, Jaakko Repola, Tomi Karjalainen, Petteri Packalen, Matti Maltamo. (2019). Transferability and calibration of airborne laser scanning based mixed-effects models to estimate the attributes of sawlog-sized Scots pines. Silva Fennica vol. 53 no. 3 article id 10179. https://doi.org/10.14214/sf.10179
Keywords: Pinus sylvestris; LIDAR; crown base height; hierarchical data; individual tree detection; sawlog quality
Highlights: Attributes of individual sawlog-sized pines estimated by transferring ALS-based models between sites; Mixed effects models were more accurate than k-NN imputation tested earlier; Calibration with a small number of field measured trees improved the accuracy.
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Airborne laser scanning (ALS) data is nowadays often available for forest inventory purposes, but adequate field data for constructing new forest attribute models for each area may be lacking. Thus there is a need to study the transferability of existing ALS-based models among different inventory areas. The objective of our study was to apply ALS-based mixed models to estimate the diameter, height and crown base height of individual sawlog sized Scots pines (Pinus sylvestris L.) at three different inventory sites in eastern Finland. Different ALS sensors and acquisition parameters were used at each site. Multivariate mixed-effects models were fitted at one site and the models were validated at two independent test sites. Validation was carried out by applying the fixed parts of the mixed models as such, and by calibrating them using 1–3 sample trees per plot. The results showed that the relative RMSEs of the predictions were 1.2–6.5 percent points larger at the test sites compared to the training site. Systematic errors of 2.4–6.2 percent points also emerged at the test sites. However, both the RMSEs and the systematic errors decreased with calibration. The results showed that mixed-effects models of individual tree attributes can be successfully transferred and calibrated to other ALS inventory areas in a level of accuracy that appears suitable for practical applications.

  • Korhonen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland ORCID http://orcid.org/0000-0002-9352-0114 E-mail: lauri.korhonen@uef.fi (email)
  • Repola, Natural Resources Institute of Finland (Luke), Natural resources, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: jaakko.repola@luke.fi
  • Karjalainen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: tomikar@uef.fi
  • Packalen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: petteri.packalen@uef.fi
  • Maltamo, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: matti.maltamo@uef.fi
article id 10055, category Research article
Jaakko Repola, Hannu Hökkä, Hannu Salminen. (2018). Models for diameter and height growth of Scots pine, Norway spruce and pubescent birch in drained peatland sites in Finland. Silva Fennica vol. 52 no. 5 article id 10055. https://doi.org/10.14214/sf.10055
Keywords: Pinus sylvestris; Picea abies; Betula pubescens; drained peatlands; forest drainage; mixed model; tree growth model
Highlights: Tree growth strongly correlated with site drainage status; Between-tree competition had a higher impact on tree diameter growth than on height growth; Growth predicted by the constructed models were calibrated using NFI11 data to ensure generally applicable growth predictions level in whole country.
Abstract | Full text in HTML | Full text in PDF | Author Info

The aim of this study was to develop individual-tree diameter and height growth models for Scots pine, Norway spruce, and pubescent birch growing in drained peatlands in Finland. Trees growing in peatland sites have growth patterns that deviate from that of trees growing in mineral soil sites. Five-year growth was explained by tree diameter, different tree and stand level competition measures, management operations and site characteristics. The drainage status of the site was influencing growth directly or in interaction with other variables. Site quality had a direct impact but was also commonly related to current site drainage status (need for ditch maintenance). Recent thinning increased growth of all species and former PK fertilization increased growth of pine and birch. Temperature sum was a significant predictor in all models and altitude for spruce and birch. The data were a subsample of the 7th National Forest Inventory (NFI) sample plots representing northern and southern Finland and followed by repeated measurements for 15–20 yrs. Growth levels predicted by the models were calibrated using NFI11 data to remove bias originating from the sample of the modelling data. The mixed linear models technique was used in model estimation. The models will be incorporated into the MOTTI stand simulator to replace the current peatlands growth models.

  • Repola, Natural Resources Institute Finland (Luke), Natural resources, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: jaakko.repola@luke.fi (email)
  • Hökkä, Natural Resources Institute Finland (Luke), Natural resources, Paavo Havaksen tie 3, FI-90014 University OF Oulu, Finland E-mail: hannu.hokka@luke.fi
  • Salminen, Natural Resources Institute Finland (Luke), Natural resources, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: hannu.salminen@luke.fi
article id 10040, category Research article
Bengt Andersson Gull, Torgny Persson, Aleksey Fedorkov, Tim J. Mullin. (2018). Longitudinal differences in Scots pine shoot elongation. Silva Fennica vol. 52 no. 5 article id 10040. https://doi.org/10.14214/sf.10040
Keywords: Pinus sylvestris; climate change; adaptation; shoot phenology; heritability of phenological traits; growth onset; growth cessation
Highlights: More northerly Scots pine origins exhibit earlier onset and cessation of shoot growth; Continental origins show more northern phenological behaviour; Heat accumulation requirements for onset are not fixed and may be lower when accumulating slower; Scots pine may suffer from spring frost due to earlier growth onset in a warming climate; Phenological traits show potential to adapt to new climate conditions by breeding.
Abstract | Full text in HTML | Full text in PDF | Author Info

Phenology can have a profound effect on growth and climatic adaptability of long-lived, northern tree species such as Scots pine (Pinus sylvestris L.), where the onset of growth in the spring is triggered mainly by accumulated heat, while cessation of growth is related to the joint effect of photoperiod and temperature. In this study, the objectives were: (1) to compare shoot phenology of genetic material from Scandinavia (maritime climate origin) and northern Russia (continental climate origin) sources, under field conditions in both Scandinavia and Russia (maritime and continental growth conditions); and (2) to estimate the heritabilities of phenological parameters. The material used was part of a larger provenance test series involving Scots pine populations and open-pollinated plus-tree families from Russia, Sweden and Finland. Terminal shoot elongation was measured on multiple occasions during the seventh growing season from seed at a trial near Bäcksjön (Sweden) and Syktyvkar (northern Russia). We calculated the regression of relative shoot elongation over accumulated heat sum above +5 °C using an exponential expression. Seedlings of Swedish and Russian provenance had similar heat-sum requirements for growth onset and cessation in both trials. More northern provenances started onset and cessation at a lower temperature sum, but heat accumulation requirements for onset were not fixed. Scots pine may suffer from spring frost due to earlier growth onset in a warming climate. Variation and heritability of phenological traits show potential to adapt Scots pine to new climate conditions by breeding.

  • Andersson Gull, The Swedish Forestry Research Institute (Skogforsk), Box 3, SE-918 21 Sävar, Sweden ORCID https://orcid.org/0000-0003-3556-3172 E-mail: bengt.anderssongull@skogforsk.se
  • Persson, The Swedish Forestry Research Institute (Skogforsk), Box 3, SE-918 21 Sävar, Sweden E-mail: torgny.persson@skogforsk.se
  • Fedorkov, The Institute of Biology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences (IB Komi SC UB RAS), Kommunisticheskaya St., 28, Syktyvkar, 167982, Russia ORCID https://orcid.org/0000-0001-7800-7534 E-mail: fedorkov@ib.komisc.ru
  • Mullin, The Swedish Forestry Research Institute (Skogforsk), Box 3, SE-918 21 Sävar, Sweden ORCID https://orcid.org/0000-0003-4924-1836 E-mail: tim.mullin@skogforsk.se (email)
article id 10013, category Research article
Hardo Becker, Jürgen Aosaar, Mats Varik, Gunnar Morozov, Kristiina Aun, Ülo Mander, Kaido Soosaar, Veiko Uri. (2018). Annual net nitrogen mineralization and litter flux in well-drained downy birch, Norway spruce and Scots pine forest ecosystems. Silva Fennica vol. 52 no. 4 article id 10013. https://doi.org/10.14214/sf.10013
Keywords: Pinus sylvestris; Picea abies; Betula pubescens; drained peatland forests; ammonification; effect of tree species; swamp; nitrification; transitional bog
Highlights: The net nitrogen mineralization (NNM) flux in drained peat soils depends largely on the C/N ratio and tree species; The soil NNM process is affected by trees through organic litter input into soil; Pine stand in low-fertility drained transitional bog is dominated by net ammonification; Birch and spruce stands on the fertile drained peat soil with higher pH and N content are dominated by net nitrification.
Abstract | Full text in HTML | Full text in PDF | Author Info

The main aim of the current study was to estimate the annual net nitrogen mineralization (NNM) flux in stands of different tree species growing on drained peatlands, as well as to clarify the effect of tree species, soil properties and litter on annual NNM dynamics. Three study sites were set up in May 2014: a downy birch (Betula pubescens Ehrh.) stand and a Norway spruce (Picea abies (L.) Karst.) stand in Oxalis full-drained swamp (ODS) and a Scots pine (Pinus sylvestris L.) stand in Myrtillus full-drained swamp (MDS). The NNM flux was estimated using the in situ method with incubated polyethylene bags. The highest value of NNM was found in stands that were growing on fertile ODS: 127.5 kg N ha–1 yr–1 and 87.7 kg N ha–1 yr–1, in the downy birch stand and in the Norway spruce stand, respectively. A significantly lower annual NNM flux (11.8 kg N ha–1 yr–1) occurred in the Scots pine stand growing in MDS. Nitrification was highest at fertile ODS sites and ammonification was the highest at the low fertility MDS site. For all study sites, positive correlation was found between soil temperature and NNM intensity. The difference in annual NNM between the downy birch stand and the Norway spruce stand growing on similar drained fertile peatlands was due to litter quality. The annual N input into the soil through leaf litter was the highest at the downy birch site where also the C/N ratio of litter was the lowest. The second highest N input into the soil was found in the spruce stand and the lowest in the pine stand.

  • Becker, Chair of Silviculture and Forest Ecology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1, 51014 Tartu, Estonia E-mail: hardo.becker@emu.ee (email)
  • Aosaar, Chair of Silviculture and Forest Ecology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1, 51014 Tartu, Estonia E-mail: jyrgen.aosaar@emu.ee
  • Varik, Chair of Silviculture and Forest Ecology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1, 51014 Tartu, Estonia E-mail: mats.varik@emu.ee
  • Morozov, Chair of Silviculture and Forest Ecology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1, 51014 Tartu, Estonia E-mail: gunnar.morozov@emu.ee
  • Aun, Chair of Silviculture and Forest Ecology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1, 51014 Tartu, Estonia E-mail: kristiina.aun@emu.ee
  • Mander, Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Ülikooli 18, 50090 Tartu, Estonia E-mail: ulo.mander@ut.ee
  • Soosaar, Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Ülikooli 18, 50090 Tartu, Estonia E-mail: kaido.soosaar@ut.ee
  • Uri, Chair of Silviculture and Forest Ecology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1, 51014 Tartu, Estonia E-mail: veiko.uri@emu.ee
article id 9946, category Research article
Frauke Fedderwitz, Niklas Björklund, Velemir Ninkovic, Göran Nordlander. (2018). Does the pine weevil (Hylobius abietis) prefer conifer seedlings over other main food sources? Silva Fennica vol. 52 no. 3 article id 9946. https://doi.org/10.14214/sf.9946
Keywords: Pinus sylvestris; Picea abies; forest regeneration; feeding preference; herbivore; plant tissues
Highlights: Adult pine weevils feed on seedlings and mature conifers, but cause economic damage only on seedlings; Their feeding preferences for branches and roots over seedlings were tested in a laboratory experiment; The only clear preference was for Norway spruce roots; Results support new approaches of seedling protection attempting to redirect pine weevils from planted seedlings to other food sources.
Abstract | Full text in HTML | Full text in PDF | Author Info

Adult pine weevils (Hylobius abietis (L.)) feed on the tender bark of branches and roots of mature conifer trees and on the stem bark of conifer seedlings. Their feeding on mature trees does not cause any economic damage, but their feeding on planted seedlings is so devastating that the pine weevil is considered one of the most important forest pest insects in Europe. We asked whether the pine weevil prefers seedlings over other regularly utilized food sources. This question is of particular interest because new approaches to seedling protection are based on decreasing any preference for seedlings by using less palatable plants or by enhancing their defence (by genetic selection or by methyl jasmonate treatment). In a laboratory choice experiment we tested pine weevil feeding preferences for seedlings compared with branches and roots from mature trees (separately for Norway spruce and Scots pine). Pine weevils preferred roots, but not branches, of Norway spruce over seedlings of the same species. With Scots pine there were no clear preferences, but the weevils showed a tendency to prefer roots over seedlings. These results provide support for seedling protection approaches that attempt to redirect pine feeding from planted seedlings to other food sources.

  • Fedderwitz, Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, SE-750 07 Uppsala, Sweden E-mail: frauke.fedderwitz@slu.se (email)
  • Björklund, Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, SE-750 07 Uppsala, Sweden E-mail: niklas.bjorklund@slu.se
  • Ninkovic, Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, SE-750 07 Uppsala, Sweden E-mail: velemir.ninkovic@slu.se
  • Nordlander, Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, SE-750 07 Uppsala, Sweden E-mail: goran.nordlander@slu.se
article id 7738, category Research article
Samuel Egbäck, Bo Karlsson, Karl-Anders Högberg, Kenneth Nyström, Mateusz Liziniewicz, Urban Nilsson. (2018). Effects of phenotypic selection on height-diameter ratio of Norway spruce and Scots pine in Sweden. Silva Fennica vol. 52 no. 2 article id 7738. https://doi.org/10.14214/sf.7738
Keywords: Pinus sylvestris; Picea abies; genetic correlations; heritability; Genetic selection; slenderness
Highlights: Swedish plus-tree selection promoted less slender Norway spruce trees and more slender Scots pine trees compared to neighboring trees; Similar results were also found for progeny trials which indicated that genetics played a prominent role in phenotypic appearance.
Abstract | Full text in HTML | Full text in PDF | Author Info

Genetically improved Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) are extensively used in operational Swedish forestry plantations. However, relatively little is known about the stem slenderness (height-diameter ratio) of genetically improved material. Thus, in this study we investigated effects of plus-tree selection on stem slenderness of Norway spruce and Scots pine in Sweden by evaluating both the plus-tree selection and a large number of progeny trials. Species-specific models for predicting the height-diameter ratio were estimated using regression and mixed model approach. Our results show that phenotypic plus-tree selection promoted less slender Norway spruce trees and more slender Scots pine trees compared to neighboring trees. Similar results were also found for the progeny trials which indicated that genetics played a prominent role in the phenotypic appearance. Compared to the progeny of neighboring trees, Norway spruce plus-tree progenies had a 5.3% lower height-diameter ratio, while Scots pine plus-tree progenies had a 1.5% greater height-diameter ratio. The narrow sense heritability for height-diameter ratio was 0.19 for Norway spruce and 0.11 for Scots pine, indicating that it is possible to modify the height-diameter ratio by breeding. Correlation coefficients between breeding values for height-diameter ratio and diameter were negative for Scots pine (–0.71) and Norway spruce (–0.85), indicating that selection for diameter only would result in less slender stems of both species. Similar correlations were also found between breeding values for height-diameter ratio and height of Scots pine (–0.34) and Norway spruce (–0.74).

  • Egbäck, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, 230 53 Alnarp, Sweden E-mail: samuel.egback@slu.se (email)
  • Karlsson, Skogforsk, Ekebo, 268 90 Svalöv, Sweden E-mail: bo.karlsson@skogforsk.se
  • Högberg, Skogforsk, Ekebo, 268 90 Svalöv, Sweden E-mail: karl-anders.hogberg@skogforsk.se
  • Nyström, Swedish University of Agricultural Sciences, Department of Forest Resource Management, Skogsmarksgränd, 901 83 Umeå, Sweden E-mail: kenneth.nystrom@slu.se
  • Liziniewicz, Skogforsk, Ekebo, 268 90 Svalöv, Sweden E-mail: Mateusz.Liziniewicz@skogforsk.se
  • Nilsson, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, 230 53 Alnarp, Sweden E-mail: urban.nilsson@slu.se
article id 7783, category Research article
Markku T. Lehtinen, Pertti Pulkkinen. (2017). Effects of Scots pine paternal genotypes of two contiguous seed orchards on the budset and frost hardening of first-year progeny. Silva Fennica vol. 51 no. 5 article id 7783. https://doi.org/10.14214/sf.7783
Keywords: Pinus sylvestris; provenance; conifer; environmental influence; pollen; genotype effect
Highlights: This environmentally controlled study on Scots pine demonstrated the effect of the paternal genotype on the budset and frost hardening of the progeny; With the applied study design, no significant indication of an environmental influence on the effect of the Scots pine paternal genotype was obtained.
Abstract | Full text in HTML | Full text in PDF | Author Info

In Scots pine (Pinus sylvestris L.), it has been shown that the parental conditions have a role in the phenological variation among first-year seedlings. For this reason, it is argued that they should be comprehensively controlled before estimating the parental genotype effects. This controlled-cross study examined the effects of a set of fathers of Scots pines on the timing of budset and autumn frost hardening of first-year seedlings. The paternal genotypes had either a northern or southern provenance, but had spent a period of over 25 years as grafts in a shared climatic environment in two closely located southern orchards. Pollen applied in the crosses was collected from these orchards in one year and all the maternal genotypes were pollinated in only one seed orchard. The results of freeze tests and budset observations of the consequent progeny were analysed and additionally compared with results obtained using seedlings from seed lots of natural forests in order to estimate the ability of northern paternal genotypes to maintain a northern effect under southern conditions. This environmentally controlled study demonstrated a significant effect of the paternal genotype on the budset and autumn frost hardening of first-year seedling of Scots pine. With the applied study design, no significant indication of an environmental influence on the effect of the paternal genotype was obtained. The accuracy of the observations is discussed. It is concluded that the results suggest a minor role of mutability in the effects of Scots pine paternal genotypes.

  • Lehtinen, University of Helsinki, Department of Agricultural Sciences, Latokartanonkaari 5 and 7, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: markku.t.lehtinen@helsinki.fi (email)
  • Pulkkinen, Natural Resources Institute Finland (Luke), Green Technology, Haapastensyrjäntie 34, FI-12600 Läyliäinen, Finland E-mail: pertti.pulkkinen@luke.fi
article id 1760, category Research article
Marek Fajstavr, Kyriaki Giagli, Hanuš Vavrčík, Vladimír Gryc, Josef Urban. (2017). The effect of stem girdling on xylem and phloem formation in Scots pine. Silva Fennica vol. 51 no. 4 article id 1760. https://doi.org/10.14214/sf.1760
Keywords: Pinus sylvestris; radial increment; cambial activity; cell differentiation; phloemogenesis; xylogenesis
Highlights: Stem girdling ceased the cambial activity, below the girdled area, immediately after the removal of the bark strip; Pinus sylvestris survived for up to two years after stem girdling; The girdled trees formed phloem cells above the girdled area but failed to form latewood cells in the next growing season.
Abstract | Full text in HTML | Full text in PDF | Author Info

Scots pine (Pinus sylvestris L.) is a resilient, wide spread species. This paper reports on the xylem and phloem cell formation process, before and after, the species was put under artificial stress by stem girdling. Microcore method was applied to a healthy control group and a standing group of girdled trees within an 80-year-old pine forest for two consecutive growing seasons (2013 and 2014). The stem girdling was applied in the middle of the first growing season (July 2013). Cambial activity timings (onset and cessation of cell division), cell formation intensity, cell differentiation, and the dynamics of the annual radial increment in the stem were analyzed. Cambial activity was inhibited and eventually ceased below the stem girdling immediately after the removal of the strip. Therefore, no latewood tracheids were formed. However, above the stem girdling and in the control trees, cell formation and tissue differentiation continued until the end of the growing season, with the girdled trees moving at a less intensive pace but for a longer period of time. During the following growing season (2014), the cambial zone was reactivated only above the stem girdling, not below, and eventually the girdled trees died. In 2014, the onset of the cambial activity was delayed and the division rate of the cells was slower in the girdled trees. Furthermore, the girdled trees formed less phloem cells than the control trees.

  • Fajstavr, Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 3, 613 00 Brno, Czech Republic E-mail: fajstavr.marek@seznam.cz (email)
  • Giagli, Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 3, 613 00 Brno, Czech Republic E-mail: kyriaki.giagli@mendelu.cz
  • Vavrčík, Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 3, 613 00 Brno, Czech Republic E-mail: vavrcik@mendelu.cz
  • Gryc, Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 3, 613 00 Brno, Czech Republic E-mail: gryc@mendelu.cz
  • Urban, Department of Forest Botany, Dendrology and Geobiocenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 3, 613 00 Brno, Czech Republic;  Siberian Federal University, Svobodnyj Prospect 79, Krasnoyarsk, 660041 Krasnoyarsk, Russia E-mail: josef.urban@email.cz
article id 5662, category Research article
Samuel Egbäck, Urban Nilsson, Kenneth Nyström, Karl-Anders Högberg, Nils Fahlvik. (2017). Modeling early height growth in trials of genetically improved Norway spruce and Scots pine in southern Sweden. Silva Fennica vol. 51 no. 3 article id 5662. https://doi.org/10.14214/sf.5662
Keywords: Pinus sylvestris; Picea abies; individual tree growth model; genetic component; genetic multiplier; unimproved material; improved material
Highlights: The developed height growth model based on unimproved material predicted the development relatively well for genetically improved Norway spruce; For genetically improved Scots pine, however, the model needed to be modified; By incorporating a genetic component into the Scots pine model, the prediction errors were reduced.
Abstract | Full text in HTML | Full text in PDF | Author Info

Genetically improved Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) are used extensively in operational Swedish forestry plantations to increase production. Depending on the genetic status of the plant material, the current estimated genetic gain in growth is in the range 10–20% for these species and this is expected to increase further in the near future. However, growth models derived solely from data relating to genetically improved material in Sweden are still lacking. In this study we investigated whether an individual tree growth model based on data from unimproved material could be used to predict the height increment in young trials of genetically improved Norway spruce and Scots pine. Data from 11 genetic experiments with large genetic variation, ranging from offspring of plus-trees selected in the late 1940s to highly improved clonal materials selected from well performing provenances were used. The data set included initial heights at the age of 7–15 years and 5-year increments for almost 2000 genetic entries and more than 20 000 trees. The evaluation indicated that the model based on unimproved trees predicted height development relatively well for genetically improved Norway spruce and there was no need to incorporate a genetic component. However, for Scots pine, the model needed to be modified. A genetic component was developed based on the genetic difference recorded within each trial, using mixed linear models and methods from quantitative genetics. By incorporating the genetic component, the prediction errors were significantly reduced for Scots pine. This study provides the first step to incorporate genetic gains into Swedish growth models and forest management planning systems.

  • Egbäck, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, 230 53 Alnarp, Sweden E-mail: samuel.egback@slu.se (email)
  • Nilsson, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, 230 53 Alnarp, Sweden E-mail: urban.nilsson@slu.se
  • Nyström, Swedish University of Agricultural Sciences, Department of Forest Resource Management, Skogsmarksgränd, 901 83 Umeå, Sweden E-mail: kenneth.nystrom@slu.se
  • Högberg, Skogforsk, Ekebo, 268 90 Svalöv, Sweden E-mail: karl-anders.hogberg@skogforsk.se
  • Fahlvik, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, 230 53 Alnarp, Sweden E-mail: nils.fahlvik@slu.se
article id 1734, category Research article
Jyrki Hytönen, Paula Jylhä, Keith Little. (2017). Positive effects of wood ash fertilization and weed control on the growth of Scots pine on former peat-based agricultural land – a 21-year study. Silva Fennica vol. 51 no. 3 article id 1734. https://doi.org/10.14214/sf.1734
Keywords: Pinus sylvestris; fertilization; vegetation management; shading; agricultural soil; overgrowth; potassium deficiency; production potential
Highlights: Weed control decreased and fertilization increased vegetation height and shading of seedlings; Weed control decreased mortality, but fertilization had no effect; Despite improved foliar K concentration though ash fertilization, all trees in the trial had severe K deficiency after 21 years; Weed control increased growth by 20 m3 ha–1 and fertilization by 35 m3 ha–1 in 21 years.
Abstract | Full text in HTML | Full text in PDF | Author Info

The impacts of weed control, ash fertilization and their interaction were tested for the afforestation of former agricultural peat-based soil with Scots pine (Pinus sylvestris L.) in northern Finland in a factorial arrangement of four treatments. Weed control with herbicides was carried out in July 1 and 2 years from planting, and wood ash (5 Mg ha–1) was applied in the spring of the 2nd year. Various vegetation, tree growth and nutrient assessments were made over the 21-year study period. Weed control decreased the weed cover by 36–56 percentage points, vegetation height by 4–26 cm and thus shading of seedlings by vegetation for at least 4 years after planting. For the same period, ash fertilization increased vegetation height by 6–15 cm and shading of seedlings. Weed control reduced seedling mortality by 27 percentage points in 21 years, but ash fertilization had no significant effect. Ash fertilization increased foliar potassium and boron concentrations, but its effect declined, and severe K-deficiency was recorded 21 years after planting. Up to the 9th year, weed control had a greater influence on growth than fertilization. Later the significance of fertilization increased due to an aggravated K-deficiency. Stand volume at year 21 for the untreated control plots was 8 m3 ha–1. Weed control and fertilization increased stand volume by 20 and 35 m3 ha–1, with a combined effect of 55 m3 ha–1. The effects of weed control and fertilization were additive and no significant interactions were found. Due to severe K-deficiencies, re-fertilization of all treatments would be necessary for the continued survival and growth of Scots pine.

  • Hytönen, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Teknologiakatu 7, FI-67100 Kokkola, Finland ORCID http://orcid.org/0000-0001-8475-3568 E-mail: jyrki.hytonen@luke.fi (email)
  • Jylhä, Natural Resources Institute Finland (Luke), Green technology, Teknologiakatu 7, FI-67100 Kokkola, Finland E-mail: paula.jylha@luke.fi
  • Little, Nelson Mandela Metropolitan University, George Campus, Western Cape, South Africa E-mail: keith.little@nmmu.ac.za
article id 1721, category Research article
Anna Hebda, Błażej Wójkiewicz, Witold Wachowiak. (2017). Genetic characteristics of Scots pine in Poland and reference populations based on nuclear and chloroplast microsatellite markers. Silva Fennica vol. 51 no. 2 article id 1721. https://doi.org/10.14214/sf.1721
Keywords: Pinus sylvestris; phylogeography; conifers; genetic divergence; population structure; microsatellite markers; neutral variation
Highlights: Similar genetic variation was found between Polish Scots pine populations from a wide variety of habitats based on nSSR and cpSSR markers; Homogeneity was observed in the genetic structures of Polish and Finnish populations from the continuous pine range; Genetic differentiation in microsatellite markers was identified only when populations from the central pine distribution were compared to the marginal stands.
Abstract | Full text in HTML | Full text in PDF | Author Info

Polymorphisms at a set of eighteen nuclear (nSSR) and chloroplast (cpSSR) microsatellite loci were investigated in sixteen populations of Scots pine (Pinus sylvestris L.) derived from the provenance trial experiment and representative of the species distribution range and climatic zones in Poland. The patterns of genetic variation were compared to the reference samples from the species distribution in Europe and Asia. A similar level of genetic variation and no evidence of population structure was found among the Polish stands. They showed genetic similarity and homogenous patterns of allelic frequency spectra compared to the Northern European populations. Those populations were genetically divergent compared to the marginal populations from Turkey, Spain and Scotland. The population structure patterns reflect the phylogeography of the species and the divergence of populations that most likely do not share recent history. As the analysed provenance trial populations from Poland are diverged in phenotypic traits but are genetically similar, they could be used to test for selection at genomic regions that influence variation in quantitative traits.

  • Hebda, University of Agriculture in Krakow, Faculty of Forestry, Institute of Forest Ecology and Silviculture, Department of Genetics and Forest Tree Breeding, 29 Listopada 46, 31-425 Kraków, Poland ORCID http://orcid.org/0000-0002-3149-8644 E-mail: ana.hebda@gmail.com (email)
  • Wójkiewicz, Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland E-mail: bwojkiew@man.poznan.pl
  • Wachowiak, Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland; Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland E-mail: witoldw@man.poznan.pl
article id 1692, category Research article
Aleksey Fedorkov, Ludmila Gutiy. (2017). Performance of lodgepole pine and Scots pine in field trials located in north-west Russia. Silva Fennica vol. 51 no. 1 article id 1692. https://doi.org/10.14214/sf.1692
Keywords: Pinus sylvestris; stem defects; mortality; Pinus contorta; stem growth
Highlights: Stem volume was bigger for lodgepole pine in comparison to local Scots pine except for the southernmost origin; The proportion of stems with no defects was lower for all lodgepole pine seed sources than for local Scots pine; Lodgepole pine stem growth traits were significantly related to latitude of seed origin.
Abstract | Full text in HTML | Full text in PDF | Author Info

Mortality, stem growth and quality of lodgepole pine (Pinus contorta var. latifolia) originating from the six Swedish seed orchards and local Scots pine (Pinus sylvestris L.) were estimated in four field trials established in the Komi Republic (north-west Russia). A randomized row-plot design with 6–12 replicates of each entry was used. The tree mortality was slightly higher for Scots pine than that for lodgepole pine, except for the lodgepole pine seed sources of the southern origins with lower survival. Scots pine stem quality was better than that of lodgepole pine, but the lodgepole pine stem growth was faster except the seed source of the southernmost origin. The lodgepole pine seed sources of northern origins had better stem growth (height, diameter at breast height and volume), while the effect of latitude on the quality traits was insignificant.

  • Fedorkov, Institute of Biology, Komi Science Center, Russian Academy of Sciences, 28 Kommunisticheskaya st., Syktyvkar 167982, Russia ORCID http://orcid.org/0000-0001-7800-7534 E-mail: fedorkov@ib.komisc.ru (email)
  • Gutiy, Syktyvkar Forest Institute (branch), Saint-Petersburg State Forest Technical University, 39 Lenin st., Syktyvkar 167000, Russia E-mail: lguti@mail.ru
article id 1564, category Research article
Stanislav Vacek, Zdeněk Vacek, Lukáš Bílek, Jaroslav Simon, Jiří Remeš, Iva Hůnová, Jan Král, Tereza Putalová, Miroslav Mikeska. (2016). Structure, regeneration and growth of Scots pine (Pinus sylvestris L.) stands with respect to changing climate and environmental pollution. Silva Fennica vol. 50 no. 4 article id 1564. https://doi.org/10.14214/sf.1564
Keywords: Pinus sylvestris; natural regeneration; climate; stand development; production; air-pollution
Highlights: Pine forest stands showed positive development of stand structural characteristics related to their diversity, number of regeneration individuals and growth characteristics; Tree-ring width was positively correlated with precipitation, while it was negatively correlated with temperature in growing seasons; Mean NOx concentrations showed positive effect on radial growth of pine; Serious defoliation was caused by SO2 concentrations and N deposition in combination with extreme climate events.
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Changes in the structure and development of managed Scots pine (Pinus sylvestris L.) stands with respect to changing environmental conditions were set for the period 1979–2015. The study was conducted in conditions of natural pinewoods and pine-oak sites on five permanent research plots (0.25 ha) in Eastern Bohemia, Czech Republic (CR). Studied forest stands showed positive development of stand structural characteristics related to their diversity, number of regeneration individuals and growth characteristics. The standing volume of regularly distributed tree layer in 2015 was in the range of 320–434 m3 ha–1, which indicates an increase by 5.9–20.0% over 10 years. Correlation between pine radial increment and the amount of precipitation was generally the strongest one. Positive statistically significant correlation between diameter increment and temperature was demonstrated only for the average March temperature of the current year. Within the CR, study site can be characterised as a medium polluted area both for sulphur and nitrogen, despite this SO2 concentrations and N deposition in combination with extreme climate events caused severe defoliation in pine stands. Conversely, radial growth was positively significantly correlated with mean NOx concentrations. Drought mainly in combination with even medium environmental pollution can further worsen the health status of pine stands in lowland areas of Central Europe. Thus, formulation of silvicultural techniques able to mitigate the impact of these stress factors is needed.

  • Vacek, Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, 165 21 Prague, Czech Republic E-mail: vacekstanislav@fld.czu.cz
  • Vacek, Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, 165 21 Prague, Czech Republic E-mail: vacekz@fld.czu.cz
  • Bílek, Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, 165 21 Prague, Czech Republic E-mail: bilek@fld.czu.cz
  • Simon, Mendel University in Brno, Faculty of Forestry and Wood Technology, Zemědělská 3, 613 00 Brno, Czech Republic E-mail: jaroslav.simon@mendelu.cz
  • Remeš, Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, 165 21 Prague, Czech Republic E-mail: remesj@email.cz (email)
  • Hůnová, Czech Hydrometeorological Institute, Na Šabatce 17 143 06 Prague, Czech Republic E-mail: hunova@chmi.cz
  • Král, Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, 165 21 Prague, Czech Republic E-mail: kraljan@fld.czu.cz
  • Putalová, Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 129, 165 21 Prague, Czech Republic E-mail: putalova@fld.czu.cz
  • Mikeska, University of Hradec Králové, Faculty of Science, Rokitanského 62, 500 03 Hradec Králové, Czech Republic E-mail: Mikeska.Miroslav@uhul.cz
article id 1565, category Research article
Teija Ruuhola, Ari Nikula, Nivala Vesa, Seppo Nevalainen, Juho Matala. (2016). Effects of bedrock and surficial deposit composition on moose damage in young forest stands in Finnish Lapland. Silva Fennica vol. 50 no. 3 article id 1565. https://doi.org/10.14214/sf.1565
Keywords: Pinus sylvestris; plantation; Alces alces; soil; damage risk; topography; geochemistry
Highlights: The effect of bedrock and soil on moose damage in forest plantations were examined; Moose damage were concentrated in nutrient rich bedrock areas; Bedrock of damaged stands contained a higher proportion of mafic and alkaline rocks; Pine-dominated stands on fine grained fertile forest sites had the highest damage risk.
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There is evidence that moose are attracted to fertile growth habitats apparently due to better quality and larger quantities of food. The nutrients in mineral soils originate from the weathering of bedrock and the composition of parental bedrock affects the fertility of produced mineral soil, thus affecting also the import of nutrients into the whole food web. We surveyed the connection between moose damage in forest plantations and the composition of bedrock and surficial deposits in Finnish Lapland. We used a database of compensated moose damage in private forests in years 1997−2010. Undamaged stands in National Forest Inventories (NFI) from years 1986–2008 served as a control data and moose-damaged NFI-stands as a reference data. Bedrock and surficial depositions and the location of studied stands in relation to ancient shorelines were explored by using the digital databases of the Geological Survey of Finland. Moose-damaged stands were concentrated in southwestern and east Lapland in the areas of the Peräpohja Schist Belt and Lapland’s Greenstone Belt that are both composed of nutrient-rich rocks. The bedrock of damaged stands contained a higher proportion of mafic and alkaline rocks than did the control stands. Moose-damaged stands were pine-dominated and grew in more fertile forest sites than did control stands. Part of pine stands probably located in soils formerly occupied by spruce, which may increase the stands’ vulnerability to biotic threats. Especially, there were relatively more moose damage in pine plantations regenerated on fine-grained mineral soils derived from nutrient rich rocks than in less fertile soils.

  • Ruuhola, Natural Resources Institute Finland (Luke), Natural Resources and Bioproduction, Yliopistokatu 6, FI-80101 Joensuu, Finland; University of Eastern Finland, Faculty of Science and Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: teija.ruuhola@uef.fi
  • Nikula, Natural Resources Institute Finland (Luke), Economics and Society, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: ari.nikula@luke.fi (email)
  • Vesa, Natural Resources Institute Finland (Luke), Economics and Society, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: vesa.nivala@luke.fi
  • Nevalainen, Natural Resources Institute Finland (Luke), Natural Resources and Bioproduction, Yliopistokatu 6, FI-80101 Joensuu, Finland E-mail: seppo.nevalainen@luke.fi
  • Matala, Natural Resources Institute Finland (Luke), Natural Resources and Bioproduction, Yliopistokatu 6, FI-80101 Joensuu, Finland E-mail: juho.matala@luke.fi
article id 1562, category Research article
Mats Erik Berlin, Torgny Persson, Gunnar Jansson, Matti Haapanen, Seppo Ruotsalainen, Lars Bärring, Bengt Andersson Gull. (2016). Scots pine transfer effect models for growth and survival in Sweden and Finland. Silva Fennica vol. 50 no. 3 article id 1562. https://doi.org/10.14214/sf.1562
Keywords: Pinus sylvestris; adaptation; tree breeding; reaction patterns; forest regeneration material
Highlights: Scots pine transfer effect models for growth and survival, valid in both Sweden and Finland have been developed; The models use high-resolution gridded climate data and can predict performance in future climatic conditions; The models perform well both for unimproved and genetically improved material and can be used to develop deployment recommendations of contemporary forest regeneration material in Sweden and Finland.
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In this study, we developed models of transfer effects for growth and survival of Scots pine (Pinus sylvestris L.) in Sweden and Finland using a general linear mixed-model approach. For model development, we used 378 provenance and progeny trials with a total of 276 unimproved genetic entries (provenances and stand seed check-lots) distributed over a wide variety of climatic conditions in both countries. In addition, we used 119 progeny trials with 3921 selected genetic entries (open- and control pollinated plus-tree families) for testing model performance. As explanatory variables, both climatic indices derived from high-resolution gridded climate datasets and geographical variables were used. For transfer, latitude (photoperiod) and, for describing the site, temperature sum were found to be main drivers for both survival and growth. In addition, interaction terms (between transfer in latitude and site altitude for survival, and transfer in latitude and temperature sum for growth) entail changed reaction patterns of the models depending on climatic conditions of the growing site. The new models behave in a way that corresponds well to previous studies and recommendations for both countries. The model performance was tested using selected plus-trees from open and control pollinated progeny tests. Results imply that the models are valid for both countries and perform well also for genetically improved material. These models are the first step in developing common deployment recommendations for genetically improved forest regeneration material in both Sweden and Finland.

  • Berlin, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: mats.berlin@skogforsk.se (email)
  • Persson, Skogforsk, Box 3, SE-91821 Sävar, Sweden E-mail: torgny.persson@skogforsk.se
  • Jansson, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: gunnar.jansson@skogforsk.se
  • Haapanen, Natural Resources Institute Finland (Luke), Green Technology, Box 18, FI-01301 Vantaa, Finland E-mail: matti.haapanen@luke.fi
  • Ruotsalainen, Natural Resources Institute Finland (Luke), Green Technology, Finlandiantie 18, FI-58450 Punkaharju, Finland E-mail: seppo.ruotsalainen@luke.fi
  • Bärring, Rossby Centre, Swedish Meteorological and Hydrological Institute, Folkborgsvägen 17, SE-60176 Norrköping, Sweden E-mail: lars.barring@smhi.se
  • Andersson Gull, Skogforsk, Box 3, SE-91821 Sävar, Sweden E-mail: bengt.andersson@skogforsk.se
article id 1514, category Research article
Heidi Hallongren, Ville Kankaanhuhta, Mikael Kukkonen. (2016). Cleaning Scots pine seedling stands with mechanical uprooters – a work quality comparison of two related devices. Silva Fennica vol. 50 no. 3 article id 1514. https://doi.org/10.14214/sf.1514
Keywords: Pinus sylvestris; productivity; early cleaning; mechanized silviculture
Highlights: The productivity of the narrower modified device was significantly better than the wider original device; Work quality did not differ significantly between devices when stand characteristics, regeneration success and pre-existing damage were taken into account; Results indicate that mechanical uprooting devices may be further developed to a cost-effective alternative to motor-manual techniques for the early cleaning of direct seeded commercial Scots pine stands.
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Commercial forests require early cleaning to ensure the unhindered and uniform growth of crop trees. In order to be cost effective, non-crop vegetation should be uprooted to prevent their recovery. Performing this work manually is a labour-intensive task but it can be done mechanically. We evaluated the efficiency of two uprooting devices in direct seeded Scots pine (Pinus sylvestris L.) stands ca. 1 m tall. Productivity and quality of the uprooting work was investigated across eight stands and ca. 160 sample plots in northern Karelia, eastern Finland. Time consumption of the uprooters was analyzed through a linear regression model and the work quality through a multilevel multivariate model in terms of the number of individual Scots pine seedlings, processing units (i.e., a bunch of seedlings to be harvested in the future) and broadleaves. The productivity of the narrower modified device was significantly better in terms of time consumption than the wider original device. Work quality did not differ significantly between devices when stand characteristics, regeneration success and pre-existing damage were taken into account. Results indicate that mechanical uprooting devices may be further developed to a cost-effective alternative to motor-manual techniques for the early cleaning of direct seeded commercial Scots pine stands.

  • Hallongren, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: heidi.hallongren@luke.fi (email)
  • Kankaanhuhta, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: ville.kankaanhuhta@luke.fi
  • Kukkonen, University of Eastern Finland, School of Forest Sciences. P.O. Box 111, FI-80101 Joensuu, Finland E-mail: mikaelkukkonen@hotmail.com
article id 1441, category Research article
Dorota Zawadzka, Stanisław Drozdowski, Grzegorz Zawadzki, Jerzy Zawadzki. (2016). The availability of cavity trees along an age gradient in fresh pine forests. Silva Fennica vol. 50 no. 3 article id 1441. https://doi.org/10.14214/sf.1441
Keywords: Pinus sylvestris; forest management; Poland; Augustów Forest; cavity-nesting birds; woodpeckers
Highlights: The density of cavity trees in pine-dominated, managed forests varied in relation to stand age and was highest in stands older than 130 years of age; Cavities excavated by woodpeckers dominated among all cavities; The number of trees with cavities appears insufficient to ensure the effective protection of bird diversity in managed stands of Augustów Forest.
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Given their importance as a resource for many forest organisms, tree cavities were inventoried in the managed pine forests of north-east Poland, in relation to the: 70–100, 101–130 and >130 year age-classes within the clear-cutting system. The densities at which cavities were present was found to depend on forest age, given that stands 70–100 years old were characterised by an average density of 0.62 trees ha–1, while forests older than 130 years reported 3.28 trees ha–1. Stands aged 70–100 years differed from those aged 130+ in having just 0.27 trees ha–1 of cavity trees, as compared with 2.91 trees ha–1. The total volume of cavity trees in stands up to 100 years old was 0.37 m3 ha–1 on average, as compared with 5.42 m3 ha–1 in stands over 130 years old. The cavities created by woodpeckers constituted 76% of all of those found, and included 53% excavated by great spotted woodpeckers (Dendrocopos major L.) and 23% by black woodpeckers (Dryocopus martius L.) The proportion of cavities excavated by D. major was highest in the youngest age class of stands. There, cavities made by D. martius constituted only 8% of the total, as compared with 31% in the oldest stands. The abundance of cavity trees thus differed along an age gradient, though in any event the availability of cavity trees appears to be too limited to provide for the needs of hole-nesting birds. Forest managers must thus take more account than hitherto of the need to protect cavity trees.

  • Zawadzka, Institute of Forest Science, University of Łódź, Branch in Tomaszów Mazowiecki, Konstytucji 3 Maja 65/67, 97-200 Tomaszów Mazowiecki, Poland E-mail: dorota_zaw@wp.pl
  • Drozdowski, Department of Silviculture, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland E-mail: stanislaw_drozdowski@sggw.pl (email)
  • Zawadzki, Eagle Conservation Committee, Okółek 14, 16-506 Giby, Poland E-mail: grzesiekgfz@op.pl
  • Zawadzki, Eagle Conservation Committee, Okółek 14, 16-506 Giby, Poland E-mail: jerzy_zaw@wp.pl
article id 1410, category Research article
Seppo Nevalainen, Juho Matala, Kari T. Korhonen, Antti Ihalainen, Ari Nikula. (2016). Moose damage in National Forest Inventories (1986–2008) in Finland. Silva Fennica vol. 50 no. 2 article id 1410. https://doi.org/10.14214/sf.1410
Keywords: Populus tremula; Pinus sylvestris; regeneration; soil preparation; thinning; Betula spp.; Keywords Alces alces; seedling stands; tree species mixture
Highlights: Almost 100 000 stands were studied; The proportion of damage doubled during the study period; Tree species mixture had a clear effect on the damage frequency; The damage was more common in mineral soils than in peatlands, in artificially than in naturally regenerated stands and in stands that needed thinning or clearing or in which soil preparation was used.
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The occurrence of moose damage was studied using data from three National Forest Inventories (NFIs) accomplished between 1986 and 2008 in Finland. The combined data included a total of 97 390 young stands. The proportion of moose damage increased from 3.6% to 8.6% between the 8th NFI (1986–1994) and the 10th NFI (2004–2008). The majority (75%) of the damage occurred in Scots pine-dominated stands. The proportion of damage was higher in aspen-dominated stands than in stands dominated by any other tree species. The tree species mixture also had a clear effect on the occurrence of damage. Pure Scots pine stands had less damage than mixed Scots pine stands, and moose damage decreased linearly with the increasing proportion of Scots pine. Stands on mineral soil had more frequent moose damage than stands on peatlands. The fertility class of the site had no straightforward effect on the damage frequency. Artificially regenerated stands had more damage than naturally regenerated stands. Accomplished soil preparation measures and the need for thinning or clearing operations increased moose damage. High proportions of moose damage in young stands were found around the country. In the 10th NFI, the largest concentration of damage was found in southwestern Finland. Our study shows the temporal and spatial changes in the occurrence of moose damage and pinpoints some important silvicultural factors affecting the relative risk of young stands over a large geographical area.

  • Nevalainen, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: seppo.nevalainen@luke.fi (email)
  • Matala, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juho.matala@luke.fi
  • Korhonen, Natural Resources Institute Finland (Luke), Economics and society, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: kari.t.korhonen@luke.fi
  • Ihalainen, Natural Resources Institute Finland (Luke), Economics and society, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: antti.ihalainen@luke.fi
  • Nikula, Natural Resources Institute Finland (Luke), Economics and society, P.O. Box 16, FI-96301 Rovaniemi, Finland E-mail: ari.nikula@luke.fi
article id 1408, category Research article
Anna Katharina Franke, Pasi Aatsinki, Ville Hallikainen, Esa Huhta, Mikko Hyppönen, Vesa Juntunen, Kari Mikkola, Seppo Neuvonen, Pasi Rautio. (2015). Quantifying changes of the coniferous forest line in Finnish Lapland during 1983–2009. Silva Fennica vol. 49 no. 4 article id 1408. https://doi.org/10.14214/sf.1408
Keywords: Pinus sylvestris; Picea abies; tree line; forest regeneration; environmental change; stand volume
Highlights: Volume of the growing stock of spruce and pine has increased in forests and in timber lines during the past 26 years; Spruce stem numbers increased on average, while pine stem numbers remained stable and location-specific variation was observed; Presuming that the ongoing trend of increasing temperature will remain, the enhanced forest regeneration and growth may result in extension of forests in the future.
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The boreal timber- and tree-line forests grow in harsh environmental conditions in their outermost distribution limit. Here even small environmental changes may cause dramatic changes in the distribution of tree species. We examined changes of the forest lines of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) in Finnish Lapland five times during 1983–2009. We monitored the number of stems and the volume of the growing stock in thirteen different locations in forest-line areas. The linear temporal trends and the variations of these response variables were used as indicators of a possible change during the study period. Spruce showed a significant increase both in the volume of the growing stock (up to 40% increase) and in the total stem number (up to 100% increase). A significant increase in the volume of the growing stock was observed in the pine data as well (up to 70% increase), whereas the stem number stagnated or even decreased. The results suggest that spruce needs favourable conditions to have an abundant regeneration, but after the establishment the seedlings seem to be more resistant against biotic and abiotic disturbances than pine seedlings. The increasing stand volume might result in a climate-related northward and upward extension of forests in the future. However, our results show that responses in the boreal forest line are species and location specific and a more favourable climate does not necessarily lead to an advance of the coniferous forest line.

  • Franke, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: anna.franke@fau.de (email)
  • Aatsinki, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: pasi.aatsinki@luke.fi
  • Hallikainen, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: ville.hallikainen@luke.fi
  • Huhta, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: esa.huhta@luke.fi
  • Hyppönen, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: mikko.hypponen@luke.fi
  • Juntunen, The Sámi Education Institute, Menesjärventie 4, P.O. Box 50, FI-99871 Inari, Finland E-mail: vesa.juntunen@sogsakk.fi
  • Mikkola, Natural Resources Institute Finland (Luke), Economics and society, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: kari.mikkola@luke.fi
  • Neuvonen, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, P.O. Box 68, FI-80101, Joensuu, Finland E-mail: seppo.neuvonen@luke.fi
  • Rautio, Natural Resources Institute Finland (Luke), Bio-based business and industry, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: pasi.rautio@luke.fi
article id 1354, category Research article
Johannes Edvardsson, Anton Hansson. (2015). Multiannual hydrological responses in Scots pine radial growth within raised bogs in southern Sweden. Silva Fennica vol. 49 no. 4 article id 1354. https://doi.org/10.14214/sf.1354
Keywords: Pinus sylvestris; peatland; dendrochronology; precipitation; hydrology; river discharge
Highlights: Annual growth of Scots pine (Pinus sylvestris L.) at Boreal raised bogs was found to reflect a synthesis of climate controlled moisture variability over the preceding one to four year period; Excessive soil moisture is a growth limiting factor for trees at raised bogs; River discharge data reflect hydrological conditions in peat bogs better than precipitation data.
Abstract | Full text in HTML | Full text in PDF | Author Info

To explore interactions between climate and peatland hydrology, Scots pine (Pinus sylvestris L.) growing at four raised bogs in southern Sweden were subject to a dendroclimatological study. Radial tree growth reflecting climate and water table fluctuations over multiannual periods was detected as significant negative correlations between tree-ring width (TRW) chronologies and the preceding one to four years total precipitation or river discharge. Systematically stronger negative correlations were obtained when river discharge instead of precipitation was compared to radial tree growth. This indicates that river discharge reflect moisture variability of peat bogs better than what precipitation data does. Meanwhile, monthly precipitation and radial tree growth did not show any clear correlation, whereas spring and early summer temperatures had a positive influence on the tree growth. Our study shows that growth variability of bog pines in the Boreal zone reflect hydrological responses related to a synthesis of climate controlled moisture variability over several year periods.

  • Edvardsson, Dendrolab.ch, Institute of Geological Sciences, University of Bern, Baltzerstrasse 1+3, CH-3012 Bern, Switzerland & Quaternary Sciences, Department of Geology, Lund University, Sölvegatan 12, SE-223 62 Lund, Sweden ORCID http://orcid.org/0000-0001-5163-1599 E-mail: johannes.edvardsson@dendrolab.ch (email)
  • Hansson, Quaternary Sciences, Department of Geology, Lund University, Sölvegatan 12, SE-223 62 Lund, Sweden E-mail: anton.hansson@geol.lu.se
article id 1301, category Research article
Mikko Moilanen, Jyrki Hytönen, Hannu Hökkä, Anssi Ahtikoski. (2015). Fertilization increased growth of Scots pine and financial performance of forest management in a drained peatland in Finland. Silva Fennica vol. 49 no. 3 article id 1301. https://doi.org/10.14214/sf.1301
Keywords: Pinus sylvestris; stand growth; peatlands; needle nutrients; P deficiency; K deficiency
Highlights: All fertilizers containing phosphorus and potassium improved the P and K status and the stem growth of Scots pine still 26 years from application; Wood ash, containing more nutrients than other fertilizers, gave the strongest stand growth response and the highest net present value; Ash fertilizer treatment outperformed other fertilizer treatments and control in net present value, regardless of the applied discount rate, 3%, 4% or 5%.
Abstract | Full text in HTML | Full text in PDF | Author Info

The long-term effects of fertilization on the needle nutrient concentrations, growth and financial performance of a Scots pine (Pinus sylvestris L.) stand was examined in a thick-peated drained peatland forest located in Central Finland. At the trial establishment in 1985, the trees were suffering from P and K deficiencies, but their N status was good. The fertilizer treatments were Control, PK (rock phosphate + potassium chloride), ApaBio (apatite phosphorus + biotite) and wood ash, applied both with and without N and replicated six times. All treatments containing phosphorus and potassium increased foliar P and K concentrations above the deficiency limits up to the end of the study period of 26 years. The effect of the fertilization on stand volume growth of Scots pine was strong and continued still at the end of the study period. The trees on ApaBio and PK plots grew nearly two-fold and those on Ash plots over two-fold compared with the control plots. In a thinning made at the end of the study period the total logging removal on fertilized plots was 1.5–2.2 times greater and included more saw logs than on the control plots. Ash fertilizer treatment outperformed other fertilizer treatments as well as the control. With a 5% discounted equivalent annual income (EAI) of Ash fertilizer treatment was statistically significantly (p=0.009) almost three times higher than that of control. As a conclusion, fertilization (either using PK fertilizers or Ash) in N-rich drained peatlands is a financially feasible method of management.

  • Moilanen, Natural Resources Institute Finland, Natural resources and bioproduction, Paavo Havaksen tie 3, FI-90014 Oulu, Finland E-mail: mikko.moilanen@luke.fi (email)
  • Hytönen, Natural Resources Institute Finland, Natural resources and bioproduction, Silmäjärventie 2, FI-69100 Kannus, Finland E-mail: jyrki.hytonen@luke.fi
  • Hökkä, Natural Resources Institute Finland, Natural resources and bioproduction, Eteläranta 55, FI-96301 Rovaniemi, Finland E-mail: hannu.hokka@luke.fi
  • Ahtikoski, Natural Resources Institute Finland, Natural resources and bioproduction, Paavo Havaksen tie 3, FI-90014 Oulu, Finland E-mail: anssi.ahtikoski@luke.fi
article id 1262, category Research article
Āris Jansons, Roberts Matisons, Māra Zadiņa, Linards Sisenis, Jānis Jansons. (2015). The effect of climatic factors on height increment of Scots pine in sites differing by continentality in Latvia. Silva Fennica vol. 49 no. 3 article id 1262. https://doi.org/10.14214/sf.1262
Keywords: Pinus sylvestris; dendroecology; height growth reconstruction; meteorological conditions; Baltic region; increment variation
Highlights: Height increment-climate relationships of Scots pine were assessed using dendrochronological techniques; Annual height increment was significantly affected by climatic factors; In western Latvia, temperature in preceding summer mainly affected height increment; In eastern Latvia height increment was affected by previous autumn temperature; During the 20th century, the effect of climatic factors has altered likely dues to climate change.
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Height growth of trees is a crucial parameter that influences the composition and productivity of forest stands and quality of timber; however, the relationships between annual height increment (HI) and climatic factors have been poorly studied. In this study, the effect of monthly mean temperature and precipitation sums on the HI of Scots pine in two sites in Latvia have been determined using dendrochronological techniques. Correlation and response function analyses were conducted for entire chronologies of HI and for 50-year intervals within them. Climatic factors significantly affected the HI of Scots pine; however, not only did the suite of significant factors differ between the sites, but the influence of these factors changed during the 20th century. In the site in western Latvia where climate is milder, temperature in the preceding summer was the main climatic determinant of HI. The effect of temperature in the dormant period and spring was significant during the first part of the 20th century, while the effect of temperature in the previous September and November has become significant since the second half of the 20th century. In the site in eastern Latvia where summers are hotter, HI has been affected by both temperature and water deficit related factors in the summer. However, since the later part of the 20th century, the effect of temperature in the previous October has intensified and become the main climatic determinant of HI.
  • Jansons,  LSFRI “Silava”, Rīgas str. 111, Salaspils, Latvia, LV2169 E-mail: aris.jansons@silava.lv
  • Matisons,  LSFRI “Silava”, Rīgas str. 111, Salaspils, Latvia, LV2169 E-mail: robism@inbox.lv (email)
  • Zadiņa,  LSFRI “Silava”, Rīgas str. 111, Salaspils, Latvia, LV2169 E-mail: mara.zadina@silava.lv
  • Sisenis, LUA Forestry Faculty, Akadēmijas str. 11, Jelgava, Latvia E-mail: linards.sisenis@llu.lv
  • Jansons, Forest Competence Centre, Dzērbenes str. 27, Riga, Latvia, LV1006 E-mail: janis.jansons@silava.lv
article id 1220, category Research article
Elisabeth Düthorn, Lea Schneider, Oliver Konter, Philipp Schön, Mauri Timonen, Jan Esper. (2015). On the hidden significance of differing micro-sites on tree-ring based climate reconstructions. Silva Fennica vol. 49 no. 1 article id 1220. https://doi.org/10.14214/sf.1220
Keywords: Pinus sylvestris; climate change; Picea abies; Finland; temperature reconstruction; RCS detrending
Highlights: Pines and spruces show growth level differences in wet and dry micro-sites with higher growth rates in the dry sites; Spruces show a robust climate-growth relationship with June-July temperatures; Application of collective detrending methods can bias long-term trends in climate reconstructions, if relict and recent samples originate from different micro-sites.
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Tree-ring chronologies are commonly extended back in time by combining samples from living trees with relict material preserved in man-made structures or natural archives (e.g. lakes). Although spatially close, these natural archives and living-tree-sites often comprise different micro-climates. Inhomogeneous growth conditions among these habitats, which may yield offsets in growth-rates, require caution in data processing. Here we assess species-specific growth dynamics in two micro-habitats and their potential effects on long chronologies by combining tree-ring data from different living-tree-sites with an “artificial” subfossil dataset. Well replicated (n > 80) Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) chronologies from northern Fennoscandia, sampled directly at the lakeshore (wet) and several meters beyond the lakeshore (dry) reveal high coherence of the variance between micro-sites (rspruce = 0.59, rpine = 0.68). Significant differences of the Regional Curves (RC) indicate faster growth of both species at the drier site though. Growth differences are more pronounced between the spruce micro-sites. The combination of recent dry and wet spruce data with artificial relict data results in two long chronologies covering the last 800 years with substantially different trends, although they consist of the same relict material and the micro-site chronologies correlate significantly over the past two centuries. The combination of spruce samples from dry inland micro-sites with subfossil samples originating from the wet lake shore can result in an underestimation of past temperatures prior to the 19th century. Such effects, hidden in the composition of long chronologies (living trees + subfossil samples) can bias long-term trends in climate reconstructions.
  • Düthorn, Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany E-mail: duethorn@uni-mainz.de (email)
  • Schneider, Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany E-mail: l.schneider@geo.uni-mainz.de
  • Konter, Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany E-mail: O.Konter@geo.uni-mainz.de
  • Schön, Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany E-mail: philipp.schoen@gmx.de
  • Timonen, Natural Resources Institute Finland (Luke), Natural resources and bioproduction, FI-96301 Rovaniemi, Finland E-mail: mauri.timonen@metla.fi
  • Esper, Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany E-mail: J.Esper@geo.uni-mainz.de
article id 1119, category Research article
Beata Woziwoda, Agnieszka Parzych, Dominik Kopeć. (2014). Species diversity, biomass accumulation and carbon sequestration in the understorey of post-agricultural Scots pine forests. Silva Fennica vol. 48 no. 4 article id 1119. https://doi.org/10.14214/sf.1119
Keywords: biodiversity; Pinus sylvestris plantation; overstorey-understorey interaction; biotic homogenization; Leucobryo-Pinetum community
Highlights: Understorey plant species diversity significantly increases with the age of a Scots pine stand; Biomass of mosses decreases by a quarter, while biomass of herbs increases several times; Total understorey’s carbon stock increases over three times. The highest amount of carbon is accumulated in understorey species like Vaccinium myrtillus and Dicranum polysetum; The growing proportion of vascular plants in the understorey biomass results in an increase in the understorey C/N ratio.
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The purpose of this study was to examine how the age of a stand of post-agricultural Scots pine forests affects the species composition, biomass and the carbon stock of the forest understorey. The community structure and species composition were studied in 75 plots (100 m2 in size), the amount of biomass, organic carbon and total nitrogen were analysed in 75 subplots (1/16 m2 in size). The plots were located in 21 plantations with the stand age of 41–60, 61–80 and over 80-years. Results show that the understorey species diversity increased with the increasing age of Scots pine stands, and the structure and species composition of secondary forests (although managed for timber production) became similar to the fresh pine forest of the European temperate region (Leucobryo-Pinetum community). Despite the increasing species diversity, however, only six understorey vascular and moss species played an important role in the biomass accumulation and C sequestration. Due to the differences in the dominant species composition, the total amount of understorey biomass significantly differed among the forest stands. The mean moss biomass ranged from 3046 kg ha–1 in 41–60-year-old stands, trough 2686 kg ha–1 in 61–80-year-old stands to 2273 kg ha–1 in over 80-year-old stands, and the mean understorey vascular plant biomass amounted to 2 kg ha–1, 1924 kg ha–1 and 3508 kg ha–1, respectively. The concentration of organic C varied considerably between species; it was the highest in Vaccinium myrtillus (50.6%) and in Dicranum polysetum (49.5%). The total mass of C was nearly 800 kg ha–1 in the youngest forests, in the subsequent age series it was two times higher and 3.5 times higher in the oldest ones. Differences in the species composition and in the C/N ratio in different species (generally higher for vascular plants and lower for mosses) were expressed in an increase in the understorey C/N ratio, which was 39.5, 46.6 and 48.6, respectively.
  • Woziwoda, Department of Geobotany and Plant Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland E-mail: woziwoda@biol.uni.lodz.pl (email)
  • Parzych, Environmental Chemistry Research Unit, Institute of Biology and Environmental Protection, Pomeranian University in Słupsk, Arciszewskiego 22b, 76-200 Słupsk, Poland E-mail: parzycha1@op.pl
  • Kopeć, Department of Geobotany and Plant Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland E-mail: domin@biol.uni.lodz.pl
article id 989, category Research article
Anna Saarsalmi, Pekka Tamminen, Mikko Kukkola. (2014). Effects of long-term fertilisation on soil properties in Scots pine and Norway spruce stands. Silva Fennica vol. 48 no. 1 article id 989. https://doi.org/10.14214/sf.989
Keywords: boreal forest; nitrogen; Pinus sylvestris L.; phosphorus; liming; forest soils; Picea abies (L.) Karst.
Highlights: N fertilisation increased the amount of carbon in the organic layer; N fertilisation decreased the C/N ratio in the surface soil; N addition increased the amount of most nutrients in the organic layer; N fertilisation tended to lower pH, although only slightly.
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The response of surface soil after 45- to 52-years to repeated nitrogen and phosphorus fertilisation was studied. This study included 30 factorial experiments established in young (5- to 30-year-old) stands using plots of 900 m2, on average, and by randomising treatments within each experiment. Total amount of N added varied from 534 to 1908 kg ha–1 and that of P from 69 to 193 kg ha–1, repeated at every second N fertilisation. Liming was performed twice; in total, 6000 kg ha–1 of dolomite was applied. Nitrogen fertilisation increased the mass of the organic layer and the amount of carbon and consequently the amounts of most of the elements in the organic layer. In both the organic layer and the 0–10 cm layer of mineral soil, nitrogen fertilisation decreased the C/N ratio and tended to lower pH, although only slightly. Phosphorus fertilisation increased the amounts of P and Ca. Liming increased the total amounts of most elements in the organic layer, except for C and N. We were able to derive models to describe how changes in the chemical properties of the surface soil depended on doses of elements and on site and stand properties.
  • Saarsalmi, Finnish Forest Research Institute, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: anna.saarsalmi@metla.fi (email)
  • Tamminen, Finnish Forest Research Institute, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: pekka.tamminen@metla.fi
  • Kukkola, Finnish Forest Research Institute, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: mikko.kukkola@metla.fi
article id 441, category Research article
Ane Zubizarreta-Gerendiain, Petri Pellikka, Jordi Garcia-Gonzalo, Veli-Pekka Ikonen, Heli Peltola. (2012). Factors affecting wind and snow damage of individual trees in a small management unit in Finland: assessment based on inventoried damage and mechanistic modelling. Silva Fennica vol. 46 no. 2 article id 441. https://doi.org/10.14214/sf.441
Keywords: Pinus sylvestris; Picea abies; Betula spp.; critical wind speed; snow loading; damage risk
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In this work, we assessed the factors affecting wind and snow damage of individual trees in a small management unit in western Finland. This was done based on inventoried damage and observed wind speeds and snow loading in storms Pyry and Janika in 2001 and Mielikki in 2002 together with mechanistic model. First, we studied which factors explain the observed damage in individual trees. Secondly, we studied how well the mechanistic model (HWIND) could predict the wind speed needed to uproot individual trees at the margins of permanent upwind edges. We found that Pyry storm caused 70% and Janika and Mielikki 18 and 12% of observed damage. In Janika storm, all trees uprooted. In other storms, both uprooting and stem breakage occurred. Scots pine suffered the most damage. Recently thinned stands on the upwind edges of open areas suffered the most damage. But, damage occurred also on soils with relatively shallow anchorage. HWIND predicted correctly damage for 69% of all uprooted trees. No-uprooting was correctly predicted for 45 and 19% of standing trees (all Scots pines), which were measured within and at the immediate upwind edge of same stands. HWIND model needs further validation at the permanent edges and/or on soils with shallow rooting to improve its prediction accuracy in such conditions.
  • Zubizarreta-Gerendiain, Technical University of Lisbon, School of Agriculture, Forest Research Centre, Lisbon, Portugal E-mail: azg@nn.po
  • Pellikka, University of Helsinki, Dept. of Geosciences and Geography, Helsinki, Finland E-mail: pp@nn.fi
  • Garcia-Gonzalo, Technical University of Lisbon, School of Agriculture, Forest Research Centre, Lisbon, Portugal E-mail: jgg@nn.po
  • Ikonen, University of Eastern Finland, School of Forest Sciences, Joensuu, Finland E-mail: vpi@nn.fi
  • Peltola, University of Eastern Finland, School of Forest Sciences, Joensuu, Finland E-mail: heli.peltola@uef.fi (email)
article id 54, category Research article
Urban Nilsson, Björn Elfving, Kjell Karlsson. (2012). Productivity of Norway spruce compared to Scots pine in the interior of northern Sweden. Silva Fennica vol. 46 no. 2 article id 54. https://doi.org/10.14214/sf.54
Keywords: Pinus sylvestris; current annual increment; mean annual increment; Picea abies; site index; yield
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Productivity of Norway spruce (Picea abies L. Karst.) and Scots pine (Pinus sylvestris L.) was studied in 12 paired plots in the interior of northern Sweden. Stands were established between 1928 and 1959; yield plots were established between 1974 and 1983 during pre-commercial thinning of the stands. Gross stem-wood production was significantly higher for Scots pine than for Norway spruce, stem-wood production by Norway spruce being 29.4% that of Scots pine. The site index for Norway spruce was lower than for Scots pine at all sites except one; the average difference in site index was 4.8 m. The simulated maximum mean annual increment (MAImax) during the rotation was 19% higher than the MAImax estimated with the site index for Scots pine, whereas simulated MAImax and MAImax estimated from the site index was about the same for Norway spruce. The simulations also indicated that MAI peaked about 50 years later for Norway spruce than for Scots pine. More small trees were included in the diameter distribution of Norway spruce than of Scots pine resulting in a lower stem-wood volume for Norway spruce when stands with the same dominant height were compared. This study shows that the difference in growth and rotation length between Scots pine and Norway spruce has implications when choosing which species to grow in the interior of northern Sweden.
  • Nilsson, Swedish University of Agricultural Sciences (SLU), Southern Swedish Forest Research Centre, Alnarp, Sweden E-mail: urban.nilsson@slu.se (email)
  • Elfving, SLU, Forest Ecology and Management, Umeå, Sweden E-mail: be@nn.se
  • Karlsson, SLU, Unit of Field Based Research, Asa, Sweden E-mail: kk@nn.se
article id 99, category Research article
Jouni Siipilehto. (2011). Local prediction of stand structure using linear prediction theory in Scots pine-dominated stands in Finland. Silva Fennica vol. 45 no. 4 article id 99. https://doi.org/10.14214/sf.99
Keywords: Pinus sylvestris; linear prediction; diameter distribution; Weibull; Johnson’s SB; height curve; stand characteristics
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This study produced a family of models for eight standard stand characteristics, frequency and basal area-based diameter distributions, and a height curve for stands in Finland dominated by Scots pine (Pinus sylvestris L.). The data consisted of 752 National Forest Inventory-based sample plots, measured three times between 1976 and 2001. Of the data, 75% were randomly selected for modelling and 25% left out for model evaluation. Base prediction models were constructed as functions of stand age, location and site providing strongly average expectations. These expectations were then calibrated with the known stand variables using linear prediction theory when estimating the best linear unbiased predictor (BLUP). Three stand variables, typically assessed in Finnish forest management planning fieldwork, were quite effective for calibrating the expectation for the unknown variable. In the case of optional distributions, it was essential to choose the weighting of the diameter distribution model such that the available input variables and the model applied were based on the same scale (e.g. arithmetic stand variables for frequency distribution). Additional input variables generally improved the accuracy of the validated characteristics, but the improvements in the predicted distributions were most noteworthy when the arithmetic mean and basal area-weighted median were simultaneously included in the BLUP estimation. The BLUP method provided a flexible approach for characterising relationships among stand variables, alternative size distributions and the height–diameter curve. Models are intended for practical use in the MOTTI simulator.
  • Siipilehto, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: jouni.siipilehto@metla.fi (email)
article id 93, category Research article
Pertti Pulkkinen, Saila Varis, Raimo Jaatinen, Aulis Leppänen, Anne Pakkanen. (2011). Increasing survival and growth of Scots pine seedlings with selection based on autumn coloration. Silva Fennica vol. 45 no. 4 article id 93. https://doi.org/10.14214/sf.93
Keywords: Pinus sylvestris; adaptation; field trials; harsh conditions; needles; nursery; selection
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This study evaluates the possibility of using autumn coloration of young Scots pine (Pinus sylvestris L.) seedlings as an indicator of adaptation to harsh climate conditions. One-year old seedlings from natural stands with different origins and seed orchards were classified as “red/reddish” and “green” based on the needle color after artificially increased night length in nursery and then measured after 14 years in field trials. In almost all the studied groups seedlings classified as “red/reddish” had significantly higher survival rate than seedlings classified as “green”. The survival of “red/reddish” was 14.2% higher than “green” among natural stand seed material and 56.2% among seed orchard material. During the study period the survival difference between “red/reddish” and “green” seedlings tended to increase. The seedling color had limited connection with the height growth, even though the trees classified as “red/reddish” were slightly taller than those classified as “green”. However, the total productivity over all field trials, described here as a heightsum, of “red/reddish” trees was 15% higher than productivity of “green” trees from natural stand material, and 61% higher than those from seed orchard material. It seems that controlled selection based on autumn color can be utilized within seed crops of different types with the aim to increase the adaptability of seed material to different environmental conditions.
  • Pulkkinen, Metla, Haapastensyrjä, Läyliäinen, Finland E-mail: pertti.pulkkinen@metla.fi (email)
  • Varis, Metla, Haapastensyrjä, Läyliäinen, Finland E-mail: sv@nn.fi
  • Jaatinen, Metla, Haapastensyrjä, Läyliäinen, Finland E-mail: rj@nn.fi
  • Leppänen, Metla, Haapastensyrjä, Läyliäinen, Finland E-mail: al@nn.fi
  • Pakkanen, Metla, Haapastensyrjä, Läyliäinen, Finland E-mail: ap@nn.fi
article id 104, category Research article
Eeva Terhonen, Teresa Marco, Hui Sun, Risto Jalkanen, Risto Kasanen, Martti Vuorinen, Fred Asiegbu. (2011). The effect of latitude, season and needle-age on the mycota of Scots pine (Pinus sylvestris) in Finland. Silva Fennica vol. 45 no. 3 article id 104. https://doi.org/10.14214/sf.104
Keywords: Pinus sylvestris; needles; harsh environment; mycota; needle age; cryptic lifecycle; Hormonema dematioides
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The seasonal and latitudinal influences on the diversity and abundance of mycota of Pinus sylvestris needles were investigated. A sample of 1620 needles resulted in a total of 3868 fungal isolates, which were assigned to 68 operational taxonomic units (OTUs). The majority of these OTUs (65%) belong to Ascomycota and only 0.03% was grouped as Basidiomycota. The dominant and most frequently isolated OTU was Hormonema dematioides. Other well-known species with a saprotrophic nutritional mode such as Lophodermium spp. were also observed. The abundance of fungi increased from fall to spring. Frequencies varied significantly in Northern and Southern Finland suggesting that factors associated with latitudinal differences have an impact on the abundance of fungi.
  • Terhonen, University of Helsinki, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: et@nn.fi (email)
  • Marco, University of Helsinki, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: tm@nn.fi
  • Sun, University of Helsinki, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: hs@nn.fi
  • Jalkanen, Finnish Forest Research Institute, Rovaniemi Research Unit, Rovaniemi, Finland E-mail: rj@nn.fi
  • Kasanen, University of Helsinki, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: rk@nn.fi
  • Vuorinen, Finnish Forest Research Institute, Suonenjoki Research Unit, Suonenjoki, Finland E-mail: mv@nn.fi
  • Asiegbu, University of Helsinki, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: fa@nn.fi
article id 29, category Research article
Piotr Androsiuk, Roman Zielinski, Kornelia Polok. (2011). B-SAP markers derived from the bacterial KatG gene differentiate populations of Pinus sylvestris and provide new insights into their postglacial history. Silva Fennica vol. 45 no. 1 article id 29. https://doi.org/10.14214/sf.29
Keywords: Pinus sylvestris; KatG gene; molecular markers; population differentiation; migrations
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The aim of the studies was to evaluate the efficiency of the KatG gene based B-SAP markers as a tool to distinguish morphologically diversified and geographically distant Scots pine populations and to track the routes of migrations. The 19 populations growing in the IUFRO 1982 provenance experiment and representing the natural distribution of the species in Europe were scored using 103 B-SAP loci. Among them 26% loci were polymorphic. The level of polymorphism was associated with the location of primers on the KatG template. The diversity was low, He = 0.086, and deposited mostly among populations. Seven unique markers were found that identified populations and likely they were associated with morphology. The overall genetic identity was relatively low, I = 0.933 (D = 0.069). The block of six B-SAP markers discriminated populations into two groups in agreement with their geographic origin and thereby further described as the North and the South. The North group was uniform with genetic diversity, He = 0.026 and the overall genetic distance D = 0.022. Presumably, it migrated from refugia in the Alps via France, northern Germany and Denmark, to Scandinavia and Russia. The South group was heterogeneous with He = 0.063 and D = 0.047. This group migrated from the Carpathians via Slovakia to Germany and Poland. The Balkans and Asian refugia did not take part in recolonization of Europe. The block of six B-SAP/KatG markers can be recommended for tracking postglacial history of Scots pine.
  • Androsiuk, University of Warmia and Mazury in Olsztyn, Department of Genetics, Plac Lodzki 3, 10-967 Olsztyn, Poland E-mail: pa@nn.pl
  • Zielinski, University of Warmia and Mazury in Olsztyn, Department of Genetics, Plac Lodzki 3, 10-967 Olsztyn, Poland E-mail: rz@nn.pl
  • Polok, University of Warmia and Mazury in Olsztyn, Department of Genetics, Plac Lodzki 3, 10-967 Olsztyn, Poland E-mail: kpolok@moskit.uwm.edu.pl (email)
article id 123, category Research article
Staffan Jacobson, Folke Pettersson. (2010). An assessment of different fertilization regimes in three boreal coniferous stands. Silva Fennica vol. 44 no. 5 article id 123. https://doi.org/10.14214/sf.123
Keywords: Pinus sylvestris; boreal forests; Picea abies; biomass yield; carbon sequestration; fertilization regimes; foliar analysis
Abstract | View details | Full text in PDF | Author Info
In 1981–82 three field experiments were established with the aim of elucidating (i) the growth response of middle-aged coniferous stands at different fertilization intensities and, hence, the economic outcomes; and (ii) the need to add nutrients other than nitrogen (N). Nutrient additions were performed at intervals of two, four, six and eight years. The experiments were established on typical podzolized and N-limited mor-humus sites, two in Scots pine (Pinus sylvestris L.) stands and one in a Norway spruce (Picea abies (L.) Karst.) stand, at three different locations in Sweden. The ages of the stands were 65–70 years at the time of establishment. Growth responses were calculated after a 22-year study period. The growth responses were significant in all treatments. The addition of nutrients other than N did not affect stem growth at any of the sites. The growth response tended to increase with decreasing application interval. The results also revealed that the efficiency of fertilization is reduced as the interval between fertilizations is shortened. Accordingly, the growth effect per kg of added N was negatively correlated to fertilization intensity. The least intensive fertilization regime (an eight-year interval) resulted in an average net increase in C sequestration of 35 kg per kg N added. The profitability, in terms of internal rate of return, the present net value at different interest rates and the cost of production, i.e. the cost to produce one extra m3 under the different N regimes, are presented and discussed.
  • Jacobson, Skogforsk, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: staffan.jacobson@skogforsk.se (email)
  • Pettersson, Skogforsk, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: fp@nn.se
article id 132, category Research article
Mats Berlin, Lars Lönnstedt, Gunnar Jansson, Öje Danell, Tore Ericsson. (2010). Developing a Scots pine breeding objective: a case study involving a Swedish sawmill. Silva Fennica vol. 44 no. 4 article id 132. https://doi.org/10.14214/sf.132
Keywords: Pinus sylvestris; economic weights; bio-economic model; tree breeding; multi-trait selection
Abstract | View details | Full text in PDF | Author Info
The aim of this study was to develop a Scots pine (Pinus sylvestris L.) breeding objective for a vertically integrated sawmill in northern Sweden. The production system was defined as comprising the sawmill and the forests supplying it. Volume per hectare, wood density, survival and straightness were used as objective traits and the related selection criteria were measurements, collected at young tree age, of height, diameter, pilodyn penetration, vitality and straightness. A bio-economic model was used to calculate economic weights for the objective traits identified. We also investigated the efficiency of different selection indices based on these economic weights, in combination with available data on genetic parameters. Furthermore, we studied the effect of different discount rates on the calculated economic weights. The results showed that, compared to the full index (which included all selection criteria), omitting either vitality or straightness had a negligible effect, reducing predicted profit gain per hectare by less than one per cent. Height or diameter each had a greater effect, with a loss of predicted profit gain per hectare of up to 6%. Excluding pilodyn penetration from the selection index caused the largest reduction in predicted profit gain per hectare, amounting to over 10%. However, when both height and diameter were removed the predicted profit gain per hectare dropped to one-third of that based on the full index. Finally, ranking and genetic selection for the developed breeding objective was insensitive to changes in the discount rate.
  • Berlin, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: mats.berlin@skogsforsk.se (email)
  • Lönnstedt, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: ll@nn.se
  • Jansson, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: gj@nn.se
  • Danell, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: od@nn.se
  • Ericsson, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: te@nn.se
article id 154, category Research article
Henrik R. Hallingbäck, Gunnar Jansson, Björn Hannrup, Anders Fries. (2010). Which annual rings to assess grain angles in breeding of Scots pine for improved shape stability of sawn timber? Silva Fennica vol. 44 no. 2 article id 154. https://doi.org/10.14214/sf.154
Keywords: Pinus sylvestris; spiral grain angle; warp; sawn timber; breeding
Abstract | View details | Full text in PDF | Author Info
The shape stability properties of sawn timber could be improved by breeding or grading Scots pine (Pinus sylvestris L.) for reduced grain angles. Currently, only grain angle assessments performed in single annual rings can be considered feasible in forest breeding programmes. The relevance of such methods in assessing shape stability traits was evaluated by taking grain angle measurements beneath the bark in a 36-year-old Scots pine progeny trial. Several grain angle measurements from stem discs were also taken from a sample of 162 trees. Phenotypic correlations were estimated between grain angle and the bow, crook and twist developed in 316 sawn and dried boards. All single annual ring assessments, including measurements taken directly under the bark, were significantly correlated with twist. The highest correlations (0.60–0.70) were observed in annual rings numbered 8–20 and at distances of 30–70 mm from the pith, indicating those parts of logs where grain angles have the largest impact on twist. These results suggests, that grain angles measured beneath the bark are relevant to the twist of sawn small timber, and that any single annual ring could be chosen for the assessment, provided that the tree diameter is within the 60–140 mm range. No appreciable correlations were observed between grain angles and either crook or bow.
  • Hallingbäck, Dept of Plant Biology and Forest Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden E-mail: henrik.hallingback@vbsg.slu.se (email)
  • Jansson, The Forestry Research Institute of Sweden, Uppsala, Sweden E-mail: gj@nn.se
  • Hannrup, The Forestry Research Institute of Sweden, Uppsala, Sweden E-mail: bh@nn.se
  • Fries, Dept of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden E-mail: af@nn.se
article id 172, category Research article
Guntis Brumelis, Maris Strazds, Zanna Eglava. (2009). Stand structure and spatial pattern of regeneration of Pinus sylvestris in a natural treed mire in Latvia. Silva Fennica vol. 43 no. 5 article id 172. https://doi.org/10.14214/sf.172
Keywords: Pinus sylvestris; regeneration; natural forest; mire
Abstract | View details | Full text in PDF | Author Info
We examined the regeneration patterns of Pinus sylvestris L. in a natural treed mire in the hemiboreal zone in Latvia. Data on tree stem age and size was collected in 207 fine-scale plots (10 m2) and 4 medium-scale plots (400 m2). Size structure of living and dead trees was also estimated on transects 180-m and 250-m length and 10-m width. In addition, the vegetation was described in 1-m2 plots to determine preferred microsites for P. sylvestris establishment. Pinus sylvestris showed continuous regeneration by an inverse J-shaped age and size structure. Pulses of mortality induced by fire were also evident. Regeneration of P. sylvestris was mostly on Sphagnum magellanicam Brid. hummocks free of competition from Ledum palustre L. and graminoids, which were found in small interspersed patches throughout the mire. The spatial pattern of tree cohorts differed, probably due to changing moisture conditions altering seedbed conditions and by fire-induced mortality in specific areas. Recent rapid invasion by Betula pubescens Ehrh. and Picea abies (L.) Karst. in a post-fire period since 1971 is probably associated with drier conditions.
  • Brumelis, Faculty of Biology, University of Latvia, Kronvalda bulv. 4, Riga LV1586, Latvia E-mail: guntis.brumelis@lu.lv (email)
  • Strazds, Faculty of Biology, University of Latvia, Kronvalda bulv. 4, Riga LV1586, Latvia E-mail: ms@nn.lv
  • Eglava, Faculty of Biology, University of Latvia, Kronvalda bulv. 4, Riga LV1586, Latvia E-mail: ze@nn.lv
article id 168, category Research article
Saila Varis, Anne Pakkanen, Aina Galofré, Pertti Pulkkinen. (2009). The extent of south-north pollen transfer in Finnish Scots pine. Silva Fennica vol. 43 no. 5 article id 168. https://doi.org/10.14214/sf.168
Keywords: Pinus sylvestris; gene flow; adaptation; coniferous phenology; plant population biology; boreal forest dynamics
Abstract | View details | Full text in PDF | Author Info
In order to evaluate the possibility of long distance gene flow in Scots pine (Pinus sylvestris L.), we measured the amount and germinability of airborne pollen and flowering phenology in central, northern, and northernmost Finland during 1997–2000. Totally 2.3% of the detected germinable pollen grains were in the air prior to local pollen shedding. The mean number of germinable pollen grains m–3 air per day was lower prior to local pollen shedding, but in the year 2000 there were more germinable pollen grains in the air of central study site prior to local pollen shedding. Prior to the onset of pollen shedding, 7.5% of female strobili which we observed were receptive. On average female strobili became receptive three days earlier than local pollen shedding started. During the period of pollen shedding in the central study site, we detected germinable airborne pollen in the northern site in years 1997, 1999 and 2000. At the northermost site, we detected germinable airborne pollen during the pollen-shedding period of the northern site in 2000. Our detection of germinable airborne pollen and synchrony of strobili maturation from south to north suggest that populations of Scots pine in central and northern Finland may provide genetic material to populations in northern and northernmost Finland, respectively.
  • Varis, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: saila.varis@metla.fi (email)
  • Pakkanen, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: ap@nn.fi
  • Galofré, Passeig de l’estació 21, 5-1, 43800 Valls, Tarragona, Spain E-mail: ag@nn.fi
  • Pulkkinen, Finnish Forest Research Institute, Haapastensyrjä Breeding Station, Karkkilantie 247, FI-12600 Läyliäinen, Finland E-mail: pp@nn.fi
article id 197, category Research article
Veli-Pekka Ikonen, Seppo Kellomäki, Heli Peltola. (2009). Sawn timber properties of Scots pine as affected by initial stand density, thinning and pruning: a simulation based approach. Silva Fennica vol. 43 no. 3 article id 197. https://doi.org/10.14214/sf.197
Keywords: three-dimensional modeling; sawing simulator; knots; Pinus sylvestris L.; shading
Abstract | View details | Full text in PDF | Author Info
The aim of this work was to analyze how different management schedules with varying initial stand density, thinning and artificial pruning of branches affect the quality, quantity and value of sawing yield in Scots pine (Pinus sylvestris L.). For this purpose, an integrated model system was employed and further developed to simulate: i) the three dimensional structure of the crown and stem of an average tree grown in a stand related to the changes in the within-stand light conditions as caused by the stand management, and ii) the sawing of logs into pieces and their quality grading based on the size and number of living and dead knots on the surfaces of sawn pieces. To maximize the quality of sawn timber, relatively dense stand is desired in the early phase of the rotation to reduce, especially in the lower part of stem, the growth of branches, and to increase the rate of dying and pruning-off of branches. In the later phase, a relatively sparse stand is desired to increase the self-pruning of branches and the occlusion of knots. However, in any case, artificial pruning is needed to maximize the knot-free zone of the stem. Also the value optimization of individual sawn pieces affects the quality and value of sawn timber. Because, only average tree was simulated, the differences between scenarios for stem volume were small. In the future, further model development is needed to analyze the development of crown and stem properties of trees with different status in a stand.
  • Ikonen, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: veli-pekka.ikonen@joensuu.fi (email)
  • Kellomäki, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: sk@nn.fi
  • Peltola, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: hp@nn.fi
article id 217, category Research article
Ville Kankaanhuhta, Timo Saksa, Heikki Smolander. (2009). Variation in the results of Norway spruce planting and Scots pine direct seeding in privately-owned forests in southern Finland. Silva Fennica vol. 43 no. 1 article id 217. https://doi.org/10.14214/sf.217
Keywords: Pinus sylvestris; Picea abies; quality control; forest regeneration survey; forest regeneration inventory; quality management
Abstract | View details | Full text in PDF | Author Info
This study describes the variation in the planting results for 3-year-old Norway spruce (Picea abies (L.) Karst.) and 4-year-old Scots pine (Pinus sylvestris L.) using direct seeding in privately-owned regeneration areas in southern Finland. The study material consists of operative forest regeneration quality management inventory areas from the years 2000–2006. The effect of both the regional and the administrative levels as well as ecological factors was modelled on the basis of the hierarchy structure forestry centre, Forest Owners’ Association (= FOA), forestry professional, regeneration area and sample plot. The major part of the variation occurred at the sample plot and regeneration area level. Particular attention was paid to observation of the clustered spatial distribution of Scots pine seedlings. The FOA and forestry professional levels explained 5% of the variation in Norway spruce planting and 11% of the variation in Scots pine direct seeding. Applied forest regeneration operations, site and soil characteristics were included in the fixed effects. In the planting of Norway spruce the most important factor explaining the regeneration result was soil preparation. Mounding produced better results than patching and disc trenching. The site and soil characteristics were other important factors in the operations. The selection of direct seeding of Scots pine on too fertile, fine textured or moist sites yielded poor results.
  • Kankaanhuhta, Finnish Forest Research Institute, Suonenjoki Research Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: ville.kankaanhuhta@metla.fi (email)
  • Saksa, Finnish Forest Research Institute, Suonenjoki Research Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: ts@nn.fi
  • Smolander, Finnish Forest Research Institute, Suonenjoki Research Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: hs@nn.fi
article id 235, category Research article
Ari Nikula, Ville Hallikainen, Risto Jalkanen, Mikko Hyppönen, Kari Mäkitalo. (2008). Modelling the factors predisposing Scots pine to moose damage in artificially regenerated sapling stands in Finnish Lapland. Silva Fennica vol. 42 no. 4 article id 235. https://doi.org/10.14214/sf.235
Keywords: Pinus sylvestris; boreal forest; forestry; Alces alces; damage; modelling
Abstract | View details | Full text in PDF | Author Info
Moose (Alces alces) damage in forest plantations have been at a high level in Finland in recent decades. Nowadays, moose is the most severe pest in Scots pine plantations also in Finnish Lapland. So far, despite the high level of damage and different bio-geographical conditions in Northern Finland, most of the moose-damage research has been carried out in Southern Finland. A number of research have also been performed to analyse factors affecting browsing but predictive models are rare. Data from 123 randomly selected and artificially regenerated pine plantations in Northern Finland were used in modelling the risk of moose browsing. The stands had been regenerated during 1984–1995. A total of 508 sample plots (range 2–8 plots per stand) were measured. Hierarchical logistic regression models with a random factor were constructed to predict the probability of leader-shoot browsing of pine on a plot. The number of planted pines and deciduous trees overtopping the pines were the most important predictors increasing the browsing probability. The results support earlier findings that deciduous trees overtopping or reaching the height of the pines should be cleaned from the immediate vicinity of the pines. Seedlings with a height ranging from 75 to 299 centimetres were more susceptible to browsing. Heavy soil scarification, such as ploughing or mounding, increased the browsing probability compared with lighter scarification methods. Soil type did not affect the browsing probability, but paludification decreased it. The within-stand variation in deciduous trees density and height should be taken into account in future moose browsing risk assessments. In Lapland, high moose damage risk areas are characterized by a low elevation and higher temperature sum.
  • Nikula, Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: ari.nikula@metla.fi (email)
  • Hallikainen, Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: vh@nn.fi
  • Jalkanen, Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: rj@nn.fi
  • Hyppönen, Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: mh@nn.fi
  • Mäkitalo, Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: km@nn.fi
article id 252, category Research article
Tuomo Kalliokoski, Pekka Nygren, Risto Sievänen. (2008). Coarse root architecture of three boreal tree species growing in mixed stands. Silva Fennica vol. 42 no. 2 article id 252. https://doi.org/10.14214/sf.252
Keywords: Pinus sylvestris; Betula pendula; Picea abies; site type; branching pattern; influence area; developmental stage
Abstract | View details | Full text in PDF | Author Info
Root system architecture determines many of the vital functions of a tree, e.g. stability of anchorage and resource uptake. The shoot:root ratio is determined through the allocation of resources. Studies on below-ground architectural elements in boreal mixed forests are relatively scarce despite the fact that knowledge on below-ground interactions and allocation changes in relation to stand developmental stage and soil fertility is needed both in ecological and silvicultural research. In this study, sixty tree root systems of three different tree species, Betula pendula, Picea abies and Pinus sylvestris, were excavated in five mixed forest stands in order to quantify differences between the species and sites in terms of rooting behaviour. Root architecture differed greatly between the species, implying different solutions for the functions of root systems. Half of the P. sylvestris had developed a taproot as a response to anchorage needs, while P. abies correspondingly had pronounced secondary growth of proximal roots. Betula pendula had the most extensive root system, illustrating the greater demand of deciduous trees for water. Betula pendula was also the most sensitive to soil fertility: it favoured exploration on the poorest site, as illustrated by the high total root length, whereas on the most fertile site its strategy was to efficiently exploit soil resources through increased branching intensity. The results obtained in this study provide basic knowledge on the architectural characteristics of boreal tree root systems for use by forestry professionals and modellers.
  • Kalliokoski, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: tuomo.kalliokoski@metla.fi (email)
  • Nygren, Department of Forest Ecology, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: pn@nn.fi
  • Sievänen, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: rs@nn.fi
article id 274, category Research article
Timo Saksa, Jari Miina. (2007). Cleaning methods in planted Scots pine stands in southern Finland: 4-year results on survival, growth and whipping damage of pines. Silva Fennica vol. 41 no. 4 article id 274. https://doi.org/10.14214/sf.274
Keywords: Pinus sylvestris; birch; competition; tending of sapling stand
Abstract | View details | Full text in PDF | Author Info
The effects of four cleaning treatments on the survival, growth of, and whipping damage to Scots pine (Pinus sylvestris L.) main stems were studied in young planted pine stands in southern Finland. Treatments were: no cleaning, point-cleaning of broadleaves (mainly birch, Betula pendula Roth and B. pubescens Ehrh.) within a radius of 1 m from the pine, topping of competing broadleaves, and total cleaning of broadleaves. A randomised complete block design with three replicates was established in five sapling stands: the mean height of the pines was 1.5 m in the three younger stands (6 or 7 years old), and 3 m in the two older stands (9 years old). Measurements taken four growing seasons later showed that in the younger stands, all cleaning treatments significantly (P < 0.05) decreased the mortality and increased the diameter increment of the pines. The height increment of the pines on point-cleaned and topped plots was significantly greater than on totally cleaned plots. In the older stands, the effects of cleaning treatments on the mortality and increment of pines were non-significant. In the younger and older stands, point-cleaning and total cleaning significantly reduced the whipping damage to pines, whereas the topping of competing broadleaves did not. The preliminary results support the use of point-cleaning in planted Scots pine stands when the mean height of the pines is about 1.5 m.
  • Saksa, Finnish Forest Research Institute, Suonenjoki Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: timo.saksa@metla.fi (email)
  • Miina, Finnish Forest Research Institute, Joensuu Unit, P.O.Box 68, FI-80101 Joensuu, Finland E-mail: jm@nn.fi
article id 300, category Research article
Jouni Siipilehto, Sakari Sarkkola, Lauri Mehtätalo. (2007). Comparing regression estimation techniques when predicting diameter distributions of Scots pine on drained peatlands. Silva Fennica vol. 41 no. 2 article id 300. https://doi.org/10.14214/sf.300
Keywords: Pinus sylvestris; drained peatland; dbh distribution; Johnson’s SB function; regression estimation methods
Abstract | View details | Full text in PDF | Author Info
We compared different statistical methods for fitting linear regression models to a longitudinal data of breast height diameter (dbh) distributions of Scots pine dominated stands on drained peatlands. The parameter prediction methods for two parameters of Johnson’s SB distribution, fitted to basal-area dbh distributions, were: 1) a linear model estimated by ordinary least squares (OLS), 2) a multivariate linear model estimated using the seemingly unrelated regression approach (SUR), 3) a linear mixed-effects model with random intercept (MIX), and 4) a multivariate mixed-effects model (MSUR). The aim was to clarify the effect of taking into account the hierarchy of the data, as well as simultaneous estimation of the correlated dependent variables on the model fit and predictions. Instead of the reliability of the predicted parameters, we focused on the reliability of the models in predicting stand conditions. Predicted distributions were validated in terms of bias, RMSE, and error deviation in the generated quantities of the growing stock. The study material consisted of 112 successively measured stands from 12 experimental areas covering the whole of Finland (total of 608 observations). Two independent test data sets were used for model validation. All the advanced regression techniques were superior to OLS, when exactly the same independent stand variables were included. SUR and MSUR were ranked the overall best and second best, respectively. Their ranking was the same in the modeling data, whereas MSUR was superior in the peatland test data and SUR in the mineral soil test data. The ranking of the models was logical, but may not be widely generalized. The SUR and MSUR models were considered to be relevant tools for practical forest management planning purposes over a variety of site types and stand structures.
  • Siipilehto, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: jouni.siipilehto@metla.fi (email)
  • Sarkkola, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: ss@nn.fi
  • Mehtätalo, University of Joensuu, Faculty of Forestry, P.O. Box 111, 80101 Joensuu, Finland E-mail: lm@nn.fi
article id 304, category Research article
Joanna Kosinska, Andrzej Lewandowski, Wladyslaw Chalupka. (2007). Genetic variability of Scots pine maternal populations and their progenies. Silva Fennica vol. 41 no. 1 article id 304. https://doi.org/10.14214/sf.304
Keywords: Pinus sylvestris L.; genetic variation; allozymes; gene conservation
Abstract | View details | Full text in PDF | Author Info
The genetic variability of Scots pine was investigated in six populations from Poland representing two maternal populations and their natural and artificial progenies. Thirteen enzyme systems controlled by 25 allozyme loci were analyzed using starch gel electrophoresis. Progeny populations maintained a high and similar level of genetic variation to that observed in the maternal populations. As expected, much closer genetic relationships were observed between maternal populations and their respective progeny than between the two maternal populations themselves. Progeny populations had the same major alleles, but differed in the number of rare alleles. Therefore, probably not all rare alleles were transferred from the maternal stands to the progenies. In addition, new rare alleles appeared in the progeny populations, possibly as a result of external pollen flow into the maternal populations.
  • Kosinska, Department of Human Medical Genetics, Medical University of Warsaw, Oczki 1, 02-007 Warsaw, Poland E-mail: jk@nn.pl
  • Lewandowski, Polish Academy of Sciences, Institute of Dendrology, 62-035 Kórnik, Poland E-mail: al@nn.pl (email)
  • Chalupka, Polish Academy of Sciences, Institute of Dendrology, 62-035 Kórnik, Poland E-mail: wc@nn.pl
article id 320, category Research article
Saija Huuskonen, Jari Hynynen. (2006). Timing and intensity of precommercial thinning and their effects on the first commercial thinning in Scots pine stands. Silva Fennica vol. 40 no. 4 article id 320. https://doi.org/10.14214/sf.320
Keywords: Pinus sylvestris; Scots pine; growth and yield; precommercial thinning; growth modelling; first commercial thinning; diameter development
Abstract | View details | Full text in PDF | Author Info
The effects of the timing and intensity of precommercial thinning on the stand diameter development and wood production in Scots pine stands was addressed. A model was developed in order to assess the thinning response of the stand diameter development. The effect of precommercial and first commercial thinning on the stand volume and the thinning removal at first commercial thinning were also modelled. The models were developed to be applicable for forest management planning purposes. The results are based on Scots pine (Pinus sylvestris L.) trials (13 experiments and 169 plots) located in Southern and Central Finland. Precommercial thinning considerably enhanced the diameter development. Precommercial thinning (at Hdom 3 m to 2000 trees per hectare) increased the mean diameter by 15% at the first commercial thinning stage (Hdom 14 m) compared to the unthinned stand (3000 trees ha–1). Early and intensive precommercial thinning resulted in the strongest response in diameter development. Wide spacing also enhanced the diameter increment. In naturally regenerated stands the diameter development was ca 13% slower than that in seeded stands. The total volume at the time of first commercial thinning was affected by the timing of thinning and the stand structure. The volume of merchantable thinning removal depended on the timing and intensity of precommercial and first commercial thinnings. Delaying the first commercial thinning from 12 meters (Hdom) to 16 meters increased the volume of thinning removal by ca.70%. The early and light precommercial thinning (Hdom 3 m, to density of 3000 trees per hectare) increased the thinning removal by 40% compared to the late and intensive precommercial thinning (at 7 meters to the density of 2000 trees per hectare).
  • Huuskonen, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: sh@nn.fi (email)
  • Hynynen, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: jh@nn.fi
article id 331, category Research article
Jouni Siipilehto. (2006). Height distributions of Scots pine sapling stands affected by retained tree and edge stand competition. Silva Fennica vol. 40 no. 3 article id 331. https://doi.org/10.14214/sf.331
Keywords: Pinus sylvestris; retention; height distribution; Weibull function; percentile prediction; edge effect
Abstract | View details | Full text in PDF | Author Info
The paper focused on the height structure of Scots pine saplings affected by (1) retained solitary pine trees or (2) a pine-dominated edge stand. The study material in (1) and (2) consisted of ten separate regeneration areas in southern Finland. In (1) 2-m radius study plots were located at 1, 3, 6 and 10 m distances from 10 systematically selected, solitary retained trees in each stand. In (2) the study plots were systematically located within 20 m from the edge stand. Competition of the individual trees was modelled using ecological field theory. The 24th and 93rd sample percentiles were used for estimating the height distribution using the two-parameter Weibull function. The models incorporated the effect of varying advanced tree competition on the predicted percentiles. Competition free dominant height was used as a driving variable for the developmental phase. Competition resulted in retarded height development within a radius of about 6 m from the retained tree, while it extended up to roughly half of the dominant height of the edge stand. The height distribution without external competition was relatively symmetrical, but increasing competition resulted in a more peaked and skewed distribution. Slight differences were found between northern sunny and southern shaded stand edges, while the least retarded height occurred at the north-western edge receiving morning sunlight. Kolmogorov-Smirnov goodness-of-fit tests showed acceptable and equal fit for both data sets; 2% and 8% of the distributions did not pass the test at the alpha 0.1 level when the Weibull distribution was estimated with the observed or predicted percentiles, respectively.
  • Siipilehto, Finnish Forest Research Institute, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: jouni.siipilehto@metla.fi (email)
article id 337, category Research article
Hannu Salminen, Risto Jalkanen. (2006). Modelling variation of needle density of Scots pine at high latitudes. Silva Fennica vol. 40 no. 2 article id 337. https://doi.org/10.14214/sf.337
Keywords: Pinus sylvestris; needles; dendroclimatology; NTM; precipitation; temperature; fascicles
Abstract | View details | Full text in PDF | Author Info
The relationship between apical extension and needle density and the effect of temperature and precipitation on needle density was modelled using data gathered from forty-nine felled sample trees in five stands of Scots pine (Pinus sylvestris L.) located along a latitudinal transect from the Arctic Circle up to the northern timberline. The lengths were measured and needle densities assessed from all annual shoots located above 1.3 metres using the Needle Trace Method (NTM), resulting, on average, in 39-year-long chronologies. The mean overall needle density was 7.8 short shoots per shoot centimetre. Needle-density variation in the measured data was mostly due to within-tree differences. Of the total variance, within-tree variation yielded 46%, between-tree 21%, and between-year 27%. The dependence of needle density on annual height growth was studied by fitting a multilevel model with random stand-, tree- and year-intercepts, the independent variables being tree age and height growth. There was a very strong negative correlation between height growth and needle density, and the proportion of between-year variance explained solely by height growth and age was 50%. The stand-wise residual variations and their correlations with the temperature and precipitation time series were further analysed with cross-correlation analysis in order to screen for additional independent variables. The only possible additional independent variable found was the precipitation of April–May (precipitation of May in the two northernmost stands). When it was added to the multi-level model, the proportion of explained between-year needle-density variance was 55%, but the overall fit of the model improved only slightly. The effect of late winter and early spring precipitation indicates the role of snow coverage and snowmelt on the growing conditions in the three southernmost stands. In general, stand-level needle-density variation is mostly due to changes in height growth.
  • Salminen, Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland E-mail: hannu.salminen@metla.fi (email)
  • Jalkanen, Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland E-mail: rj@nn.fi
article id 349, category Research article
Temel Sariyildiz, J. M. Anderson. (2006). Intra-specific variation in cell wall constituents of needle age classes of Pinus sylvestris in relation to soil fertility status in Southwest England. Silva Fennica vol. 40 no. 1 article id 349. https://doi.org/10.14214/sf.349
Keywords: Pinus sylvestris; nitrogen; soil fertility; lignin; needle age classes; phenylpropanoids; hemicellulose
Abstract | View details | Full text in PDF | Author Info
First, second and third year needles were collected from the same branches of young Scots pine trees growing on soils of two different status (high and low fertility sites) that varied in mineral nutrient concentrations and N mineralisation potential. All needle age classes were analysed for total carbon, acid detergent fibre (ADF), lignin, cellulose, phenylpropanoid derivatives (PPD) of lignin, sugar constituents of non-crystalline, hydrated cellulose and hemicellulose, and nutrient concentrations (N, P, K, Ca, Mg and Mn). Significant intra-specific variation in the litter quality variables in relation to soils of high and low fertility was found in the second and third year needles, whereas there were no differences in the other cell wall constituents and mineral elements of the first year needles. The second and third year needles from the low fertility soil contained higher concentrations of ADF, lignin, cellulose, sugar constituents of non-crystalline, hydrated cellulose and hemicellulose, and phenylpropanoid derivatives (PPD) of lignin, but lower concentrations of N, P and Mg than the same needles from the high fertility and fertilised soils. The results in the present study indicate that under different soil fertilities, needle age classes show significant variations in the cell wall constituents and mineral elements, and suggest that this can result in significant variation in litter quality and decomposition rates.
  • Sariyildiz, Kars Kafkas Üniversitesi, Artvin Orman Fakültesi, 08000 Artvin, Turkey E-mail: t_sariyildiz@yahoo.com (email)
  • Anderson, Department of Biological Sciences, Hatherly Laboratories, University of Exeter, Exeter EX4 4PS, UK E-mail: jma@nn.uk
article id 362, category Research article
Hannu Salminen, Risto Jalkanen. (2005). Modelling the effect of temperature on height increment of Scots pine at high latitudes. Silva Fennica vol. 39 no. 4 article id 362. https://doi.org/10.14214/sf.362
Keywords: Pinus sylvestris; height growth; dendroclimatology; precipitation; temperature
Abstract | View details | Full text in PDF | Author Info
The effect of temperature and precipitation on the height increment of Pinus sylvestris (L.) was modelled using data gathered from a total of 49 felled sample trees from five stands of Scots pine located along a latitudinal transect from the Arctic Circle up to the northern timberline in Finland. A multilevel mixed effects model and cross-correlation analysis of prewhitened time series was used to analyse the dependence between height increment and monthly meteorological observations. The effect of the mean July temperature of the previous year on height increment proved to be very strong at high latitudes (r > 0.7). The mean November temperature of the year before the previous affected statistically significantly on height increment in the three northernmost stands. There was no correlation between height increment and precipitation in any of the sites. The final height increment model based on all stands included tree age, long-term mean temperature sum of site, and the mean July temperature of the previous year as independent variables. According to the model, one degree’s change in July temperature results on average in 1.8 cm change in the next year’s height increment. There was a modest but significant polynomial age-effect. The proportion of explained variance (at the year level) was 74%. The July temperature dependence on height increment was shown to be very strong, suggesting a high value of height increment in climate modelling at the tree line.
  • Salminen, Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland E-mail: hannu.salminen@metla.fi (email)
  • Jalkanen, Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland E-mail: rj@nn.fi
article id 393, category Research article
Seppo Rouvinen, Anne Rautiainen, Jari Kouki. (2005). A relation between historical forest use and current dead woody material in a boreal protected old-growth forest in Finland. Silva Fennica vol. 39 no. 1 article id 393. https://doi.org/10.14214/sf.393
Keywords: Populus tremula; Pinus sylvestris; Picea abies; coarse woody debris; forest utilization; historical ecology; land-use history; nature conservation; spatial pattern analysis
Abstract | View details | Full text in PDF | Author Info
Assessing the human impact on the naturalness and vegetation characteristics of protected areas is one of the key issues when designing forest conservation networks in Fennoscandia. We studied the small-scale, detailed relationship between forest utilization history and the current availability of dead woody material in a protected old-growth forest area in North Karelia, eastern Finland. From the study area of 32.4 ha, all the stumps (diameter ≥ 5 cm and height < 1.3 m, classified as natural, man-made and of undetermined origin) were measured using 25 x 25 m sub-plots. Standing and fallen dead trees (dbh ≥ 5 cm) were measured on 50 x 50 m plots in an area of 7.8 ha. The average number of stumps was 130 per ha, and over half of the stumps were classified as man-made. However, the historical documents since the 1910s showed no logging in the area: some of the largest man-made stumps probably originated from an earlier time, but most of those stumps were made considerably later. The variation in the total number of stumps (per ha) was great (range 0–560/ha, 0–16 m2/ha), with no clear clustering in space. However, clustering of man-made stumps was detected. The average volume of pooled standing and fallen trees was 84 m3/ha, with a range of 37–146 m3/ha. The other noticeable man-made disturbance besides logging was notching of aspens, which has a scatteredly significant influence on the amount of dead trees. In conclusion, the protected old-growth forest was not as a whole in a natural state but showed different degrees of human impact from virtually untouched patches to quite heavily managed patches. The results suggest that the number of man-made stumps may be a relatively quick and easy method of assessing the naturalness of woody biomass structure in the Fennoscandian boreal forests.
  • Rouvinen, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: seppo.rouvinen@joensuu.fi (email)
  • Rautiainen, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ar@nn.fi
  • Kouki, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: jk@nn.fi
article id 408, category Research article
Sakari Sarkkola, Hannu Hökkä, Timo Penttilä. (2004). Natural development of stand structure in peatland Scots pine following drainage: results based on long-term monitoring of permanent sample plots. Silva Fennica vol. 38 no. 4 article id 408. https://doi.org/10.14214/sf.408
Keywords: Pinus sylvestris; peatland; tree mortality; stand structure; drainage; dbh distribution
Abstract | View details | Full text in PDF | Author Info
We studied the dynamics of stand structure on drained peatland sites in Scots pine dominated stands untreated with thinnings. The data consisted of consecutive stand measurements in 10 permanent sample plots where the monitoring periods varied from 29 to 66 years. We assumed that the stand’s structural development was driven by the natural processes of regeneration, growth, and mortality, all related to inter-tree competition within the stand. The DBH distributions of live and dead trees at different times of post-drainage stand development – smoothed by Weibull function – were analysed to characterise the change in stand structure. The initial uneven-sized structure of the natural, widely-spaced stands became more uneven during the first decades following drainage due to enhanced regeneration. Later, as stand density and mean tree size continuously increased, the DBH distributions approached bell-shaped distributions. Accordingly, the suppressed trees showed their highest mortality rate during the first decades, but the peak of the mortality distribution shifted to larger trees along stand succession. The change in structure was faster in southern Finland than in northern Finland. We assumed the changes in stand dynamics reflected increased inter-tree competition, initiated by enhanced site productivity and increased stand stocking resulting from the ditching operation.
  • Sarkkola, University of Helsinki, Department of Forest Ecology, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: sakari.sarkkola@helsinki.fi (email)
  • Hökkä, Finnish Forest Research Institute, Rovaniemi Research Station, P.O. Box 16, FI-96301 Rovaniemi, Finland E-mail: hh@nn.fi
  • Penttilä, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: tp@nn.fi
article id 407, category Research article
Soili Kojola, Timo Penttilä, Raija Laiho. (2004). Impacts of different thinning regimes on the yield of uneven-structured Scots pine stands on drained peatland. Silva Fennica vol. 38 no. 4 article id 407. https://doi.org/10.14214/sf.407
Keywords: Pinus sylvestris; stand structure; silviculture; growth and yield; peatland forestry; intermediate cuttings
Abstract | View details | Full text in PDF | Author Info
Drained peatlands in northern Europe comprise more than 10 million ha of forestland and thus constitute a considerable production potential in forestry. Much of this area consists of stands dominated by Scots pine and close to maturity regarding commercial thinning. The trees within these stands typically vary in terms of age, size, and growth rate. The impacts of silvicultural cuttings on these uneven-structured stands are inadequately known. We simulated the impacts of a control regime with no thinnings, and three different thinning regimes, involving different thinning intensities, on the development of fifteen pine-dominated stands in Finland. The simulations started from the first thinnings and were continued until regeneration maturity. The predicted total yields ranged from 244 to 595 m3 ha–1, depending on site and thinning regime. The highest total yields were observed for the control regime in which 18–38% of the yield was, however, predicted to self-thin by the end of the simulation. Thus, the differences in the yields of merchantable wood were fairly small among the compared regimes. However, the regimes involving thinnings generally needed less time than the control regime to reach regeneration maturity. The mean annual increment of total stem volume was at its highest in the control regime. The highest mean annual increment of merchantable wood was obtained in the regime involving two moderate thinnings, but excluding the most low-productive sites where thinnings did not increase the yield of merchantable wood.
  • Kojola, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: soili.kojola@metla.fi (email)
  • Penttilä, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: tp@nn.fi
  • Laiho, University of Helsinki, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: rl@nn.fi
article id 424, category Research article
Mats Warensjö, Göran Rune. (2004). Stem straightness and compression wood in a 22-year-old stand of container-grown Scots pine trees. Silva Fennica vol. 38 no. 2 article id 424. https://doi.org/10.14214/sf.424
Keywords: Pinus sylvestris; stem form; eccentricity; reaction wood
Abstract | View details | Full text in PDF | Author Info
The distribution of compression wood in relation to eccentric growth and development of stem straightness was studied in a 22-year-old Scots pine (Pinus sylvestris L.) stand in central Sweden that was established with container-grown seedlings. Stem straightness was measured on the same 440 trees in 1986 and 1997. The number of stems with straight base sections increased from 60% in 1986 to 89% in 1997. Measurements of 72 sample trees in 2001 showed that 96% of the trees had developed straight stem bases. External geometry data of the logs was obtained with a Rema 3D log scanner. A sub-sample of 16 trees was randomly selected for analysis of compression wood distribution and eccentricity measurements. From each tree, 11 discs were cut at every 60 cm along the stem. All discs, except one, contained compression wood. Compression wood and pith eccentricity was most pronounced near the stem base but not significantly correlated to basal sweep. Severe compression wood content was correlated to pith eccentricity and bow height. In general, correlations were better for the basal sections of the logs. Even though most trees were straight, they contained large amounts of compression wood. It is evident that eccentric growth and compression wood formation play major roles in the development of stem straightness. In several stems, a spiral compression wood distribution pattern was found. Reasons for this are discussed.
  • Warensjö, Department of Forest Products and Markets, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden E-mail: mats.warensjo@spm.slu.se (email)
  • Rune, Department of Forestry and Wood Technology, Dalarna University, SE-776 98 Garpenberg, Sweden E-mail: gr@nn.se
article id 436, category Research article
Martti Varmola, Hannu Salminen, Mauri Timonen. (2004). Thinning response and growth trends of seeded Scots pine stands at the arctic timberline. Silva Fennica vol. 38 no. 1 article id 436. https://doi.org/10.14214/sf.436
Keywords: Pinus sylvestris; thinning; growth and yield; northern timberline
Abstract | View details | Full text in PDF | Author Info
Growth patterns and reactions of Scots pine (Pinus sylvestris L.) to thinning in extremely harsh climatic conditions were studied in two seeded Scots pine stands located on the arctic timberline. Coniferous trees usually do not form closed stands at the timberline, but occur only in scattered tree groups. The trial was established in two stands in 1985–1986 when the trees were at an age of 47 and 56 years and an average dominant height of 6.0–6.9 m. The trial was remeasured in 1998. The thinning treatments reduced the stem number for five different levels; final density of 300, 550, 800, 1050, and 1300 stems ha–1 and unthinned. The experiment had a randomised block design with four replications in each stand. The increased growing space provided by thinning accelerated diameter growth after a delay of 2–3 years. The differences between the radial growth of the thinning treatments were very clear during the whole 13- to 14-year observation period. Annual increment of the mean diameter was regularly the higher, the larger the spacing. Dominant diameter was less influenced by treatments. There were no significant differences in dominant height between any of the treatments. Both basal area and volume were regularly the greater the higher the stem number was. Even a relatively light thinning had a distinct positive effect on tree growth, i.e. not carrying out thinning resulted in a production loss of merchantable wood. According to the results, seeded stands on the arctic timberline can grow surprisingly well in favourable conditions and reach a dominant height of 12–14 m in 100 years and a mean annual increment of 1.0–1.5 m3 ha–1 y–1 over a rotation period of 130–160 years. Based on increment figures and thinning reactions, a spacing of ca. 1000 stems ha–1 can be recommended.
  • Varmola, The Finnish Forest Research Institute, Rovaniemi Research Station, P.O.Box 16, FIN-96301 Rovaniemi, Finland E-mail: martti.varmola@metla.fi (email)
  • Salminen, The Finnish Forest Research Institute, Rovaniemi Research Station, P.O.Box 16, FIN-96301 Rovaniemi, Finland E-mail: hs@nn.fi
  • Timonen, The Finnish Forest Research Institute, Rovaniemi Research Station, P.O.Box 16, FIN-96301 Rovaniemi, Finland E-mail: mt@nn.fi
article id 432, category Research article
Bo Långström, Claes Hellqvist, Jan Cedervind. (2004). Comparison of methods for estimation of needle losses in Scots pine following defoliation by Bupalus piniaria. Silva Fennica vol. 38 no. 1 article id 432. https://doi.org/10.14214/sf.432
Keywords: Pinus sylvestris; pine looper; undefoliated foliage; needle biomass; CIR-pictures
Abstract | View details | Full text in PDF | Author Info
In 1996, ca. 7000 hectares of pine forests at Hökensås in SW Sweden were defoliated by the pine looper, Bupalus piniara (L.) (Lepidoptera. Geometridae). Following an aerial damage survey using CIR (colour infra red) photography, and estimation of pupal densities in the soil, ca 4000 ha of the most defoliated pine stands were sprayed in early August 1997 with Bacillus thuringiensis var. kurstaki. The control operation was succeessful but probably redundant, as no further defoliation occurred in unsprayed reference areas. In order to assess defoliation levels in different damage classes for later growth loss studies, 47 circular study plots were laid out in pine stands representing different damage and age classes. The remaining foliage was recorded for each tree using the following classes: 0, 10, 30, 50, 70, 90 and 100%. The defoliation levels in 1996 were estimated by disregarding the 1997 needle age class. Thirteen ca. 40-year-old sample trees representing different damage classes were felled, and the remaining foliage of all branches was estimated by needle age class using the above-mentioned scale. One branch in each of the whorls 1996, 1991, 1986 and 1981 was sampled and its needle dry weight was determined. The sample branch data confirmed the field observations that virtually no additional defoliation took place in 1997. The damage classes estimated from the CIR-pictures only agreed with the field damage estimates at the higher end of the damage scale. In contrast, the field estimate correlated well with plot means derived from tree-wise estimates (R2 = 0.93), and with with the calculated needle biomasses per tree (R2 = 0.90). Thus, the field damage classification was supported by the more detailed defoliation estimates, and hence forms a relevant basis for later growth loss studies.
  • Långström, SLU, Dept. of Entomology, P.O.Box 7044, S-750 07 Uppsala, Sweden. Fax +46 18 672 890 E-mail: bo.langstrom@entom.slu.se (email)
  • Hellqvist, SLU, Dept. of Entomology, P.O.Box 7044, S-750 07 Uppsala, Sweden. Fax +46 18 672 890 E-mail: ch@nn.se
  • Cedervind, SLU, Dept. of Entomology, P.O.Box 7044, S-750 07 Uppsala, Sweden. Fax +46 18 672 890 E-mail: jc@nn.se
article id 483, category Research article
Staffan Jacobson. (2003). Addition of stabilized wood ashes to Swedish coniferous stands on mineral soils - effects on stem growth and needle nutrient concentrations. Silva Fennica vol. 37 no. 4 article id 483. https://doi.org/10.14214/sf.483
Keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; foliar analysis; N fertilization; recycling
Abstract | View details | Full text in PDF | Author Info
Increasing use of forest fuels for energy production is generating increasing quantities of wood ash. A common understanding is that this ash should be spread in forests to counteract soil acidification and potential future nutrient deficiencies, and thus help sustain long-term forest productivity. A series of seven field experiments was established in Sweden in 1988–1995 to study the stem growth and needle nutrient concentrations of 30–60-year-old Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands on mineral soil after additions of wood ash in different doses or a combination of wood ash and N. The results showed that the most pronounced growth responses occurred when N was added, either alone or in combination with wood ash. The stem growth responses to additions of wood ash without N were small and variable, and not statistically significant at any of the studied experimental sites. However, there were indications that the addition of wood ash may increase stem-wood growth on fertile sites and decrease it on less fertile sites. In the short term, the addition of wood ash tended to increase the needle nutrient concentrations of most analyzed elements, except for N, but this could not be correlated to responses in stem growth.
  • Jacobson, The Forestry Research Institute of Sweden, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: staffan.jacobson@skogforsk.se (email)
article id 494, category Research article
Antero Varhimo, Soili Kojola, Timo Penttilä, Raija Laiho. (2003). Quality and yield of pulpwood in drained peatland forests: pulpwood properties of Scots pine in stands of first commercial thinnings. Silva Fennica vol. 37 no. 3 article id 494. https://doi.org/10.14214/sf.494
Keywords: Pinus sylvestris; peatland; thinning; silviculture; pulpwood; fiber; pulping
Abstract | View details | Full text in PDF | Author Info
The inherent structural dynamics of drained peatland forests may result in a great variation in various wood and fiber properties. We examined variation in fiber and pulp properties i) among stands, ii) among trees within stands, and iii) within trees in young stands dominated by Scots pine (Pinus sylvestris L.). The stands, selected to cover a maximal range of the potential variation, were all at a stage of development where the first commercial thinnings would be feasible. Differences in the processability of the thinning removals were small. In similar kraft cooking conditions, a 5-unit variation in the kappa number of unbleached pulp was observed among the stands. Stand origin had no effect on pulp bleaching. The wood formed prior to drainage had a higher density, shorter fibers, was slightly slower delignified by cooking, and its yield was slightly lower than that of post-drainage wood. These properties, except for high density, are typical for juvenile wood in general, and at stand level they did not correlate with the proportion of pre-drainage wood. When the variation in fiber and pulp properties was broken down into its components, most of it was derived from tree-level in all the cases. On average, the fiber and pulp properties did not differ from those observed for first-thinning pulpwood from upland sites. Consequently, peatland-grown pulpwood may be mixed with other pulpwood in industrial processes. It would probably be best suited as the raw material for pulps with high bonding requirements, e.g. in the top ply of multi-ply board grades or in some specialty grades.
  • Varhimo, KCL, P.O. Box 70, FIN-02151 Espoo, Finland E-mail: antero.varhimo@kcl.fi (email)
  • Kojola, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: sk@nn.fi
  • Penttilä, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: sp@nn.fi
  • Laiho, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: raija.laiho@helsinki.fi
article id 493, category Research article
Göran Rune. (2003). Slits in container wall improve root structure and stem straightness of outplanted Scots pine seedlings. Silva Fennica vol. 37 no. 3 article id 493. https://doi.org/10.14214/sf.493
Keywords: Pinus sylvestris; solidwall container; slitwall container; root morphology; mechanical instability; stem straightness
Abstract | View details | Full text in PDF | Author Info
Root structure and basal sweep were measured on 6-year-old Scots pine (Pinus sylvestris L.) trees at two sites with different soil fertility. Each site was planted with seedlings of identical origin after nursery cultivation in either solidwall container types with vertical ribs or in slitwall container types. Neither container design nor container volume affected tree height or stem diameter on the two sites. The transversal area of lateral roots was larger than the transversal area of bottom roots for the two container types at both sites. The proportion of bottom root transversal area to the total root transversal area was larger in the seedlings growing on the low fertility site than in those growing in the high fertility site for both container types. Seedlings cultivated in slitwall containers had a larger root area in proportion to stem diameter and had less root spiralling compared to the trees cultivated in solidwall containers. At the high fertility site, trees from the slitwall container type had straighter stem bases than seedlings grown in solidwall containers. At the low fertility site, differences in basal sweep formation were small between the container types. Reasons for this are discussed.
  • Rune, Dalarna University, Department of Forestry and Wood Technology, SE-776 98 Garpenberg, Sweden E-mail: gru@du.se (email)
article id 492, category Research article
Seppo Kaunisto, Tytti Sarjala. (2003). Foliar potassium concentrations of bilberry, bog bilberry and downy birch as indicators of potassium nutrition of Scots pine on a drained peatland. Silva Fennica vol. 37 no. 3 article id 492. https://doi.org/10.14214/sf.492
Keywords: Pinus sylvestris; peatland; foliar analysis; dormancy; B. pubescens; deficiency; deficiency limit; needle analysis; potassium; putrescine; V. myrtillus; V. uliginosum
Abstract | View details | Full text in PDF | Author Info
Leaves of bilberry (V. myrtillus), bog bilberry (V. uliginosum) and downy birch (B. pubescens) were collected five times during a growing season from 18 plots in a drainage area, and needles of Scots pine (Pinus sylvestris L.) once during the following winter from the same plots at Parkano, southern Finland. The aim was to study the potassium nutrition of the test plants and relationships between the foliar potassium concentrations of Scots pine and of the test plants. The estimation of the potassium nutrition of test plants was based on the accumulation of putrescine in foliage. Apart from single observations, elevated putrescine concentrations were found when the potassium concentrations were < 5 mg g–1 in bilberry, < 4 mg g–1 in bog bilberry and < 6 mg g–1 in downy birch, and the highest concentrations below the potassium levels of 3.0–3.5 mg g–1. At the concentrations of 2–3 mg g–1 the accumulation increased pronouncedly in bog bilberry but less in downy birch and only slightly in bilberry. The foliar potassium concentrations in test plants correlated closely with the concentrations in pine needles. The concentrations of all species in August were quite stable at the levels of the severe and slight potassium deficiency of pine (3.5 and 4.5 mg g–1 respectively) indicating that August would be suitable for collecting foliage. The concentrations in bog bilberry were very close to the concentrations in pine at the severe and those in bilberry at the slight deficiency level of pine. All test plants could be used for predicting the potassium nutrition of Scots pine, but additional research is needed for the practical application of the method.
  • Kaunisto, Finnish Forest Research Institute, Parkano Research Station, Kaironiementie 54, FIN-39700 Parkano, Finland E-mail: seppo.kaunisto@metla.fi (email)
  • Sarjala, Finnish Forest Research Institute, Parkano Research Station, Kaironiementie 54, FIN-39700 Parkano, Finland E-mail: ts@nn.fi
article id 504, category Research article
Sylvain Jutras, Hannu Hökkä, Virpi Alenius, Hannu Salminen. (2003). Modeling mortality of individual trees in drained peatland sites in Finland. Silva Fennica vol. 37 no. 2 article id 504. https://doi.org/10.14214/sf.504
Keywords: Pinus sylvestris; Betula pubescens; simulation; peatlands; mortality; generalized linear mixed models; multilevel models
Abstract | View details | Full text in PDF | Author Info
Multilevel logistic regression models were constructed to predict the 5-year mortality of Scots pine (Pinus sylvestris L.) and pubescent birch (Betula pubescens Ehrh.) growing in drained peatland stands in northern and central Finland. Data concerning tree mortality were obtained from two successive measurements of the National Forest Inventory-based permanent sample plot data base covering pure and mixed stands of Scots pine and pubescent birch. In the modeling data, Scots pine showed an average observed mortality of 2.73% compared to 2.98% for pubescent birch. In the model construction, stepwise logistic regression and multilevel models methods were applied, the latter making it possible to address the hierarchical data, thus obtaining unbiased estimates for model parameters. For both species, mortality was explained by tree size, competitive position, stand density, species admixture, and site quality. The expected need for ditch network maintenance or re-paludification did not influence mortality. The multilevel models showed the lowest bias in the modeling data. The models were further validated against independent test data and by embedding them in a stand simulator. In 100-year simulations with different initial stand conditions, the models resulted in a 72% and 66% higher total mortality rate for the stem numbers of pine and birch, respectively, compared to previously used mortality models. The developed models are expected to improve the accuracy of stand forecasts in drained peatland sites.
  • Jutras, Département des sciences du bois et de la forêt, Université Laval, Ste-Foy, Québec, G1K 7P4, Canada E-mail: sj@nn.ca
  • Hökkä, Finnish Forest Research Institute, Rovaniemi Research Station, P.O. Box 16, FIN 96301 Rovaniemi, Finland E-mail: hannu.hokka@metla.fi (email)
  • Alenius, Finnish Forest Research Institute, Rovaniemi Research Station, P.O. Box 16, FIN 96301 Rovaniemi, Finland E-mail: va@nn.fi
  • Salminen, Finnish Forest Research Institute, Rovaniemi Research Station, P.O. Box 16, FIN 96301 Rovaniemi, Finland E-mail: hs@nn.fi
article id 499, category Research article
Mikhail V. Kozlov, Pekka Niemelä. (2003). Drought is more stressful for northern populations of Scots pine than low summer temperatures. Silva Fennica vol. 37 no. 2 article id 499. https://doi.org/10.14214/sf.499
Keywords: Pinus sylvestris; climate change; precipitation; stress; temperature; fluctuating asymmetry; Kola peninsula
Abstract | View details | Full text in PDF | Author Info
Needle fluctuating asymmetry, which is a non-specific stress indicator, was used to evaluate responses of Scots pine (Pinus sylvestris L.) to annual climatic variation in the Kola Peninsula, NW Russia, during 1992–1999. Although the 30 trees surveyed for this study demonstrated individualistic responses to the temperature and precipitation of the growth seasons, at the population level we found no effect of temperature and a significant increase in fluctuating asymmetry with a decline in precipitation during the previous August. This finding suggests that the vitality of Scots pine populations at the northern tree limit is controlled by late summer precipitation rather than by temperatures of the growth season.
  • Kozlov, Section of Ecology, University of Turku, 20014 Turku, Finland E-mail: mikoz@utu.fi (email)
  • Niemelä, Forestry Faculty, University of Joensuu, P.O. Box 111, 80101 Joensuu, Finland E-mail: pn@nn.fi
article id 498, category Research article
Slobodan B. Mickovski, A. Roland Ennos. (2003). Anchorage and asymmetry in the root system of Pinus peuce. Silva Fennica vol. 37 no. 2 article id 498. https://doi.org/10.14214/sf.498
Keywords: Pinus sylvestris; eccentricity; root morphology; anchorage; asymmetry; Pinus peuce; clustering
Abstract | View details | Full text in PDF | Author Info
The relationship between the anchorage mechanics and root architecture of Pinus peuce was investigated by carrying out winching tests and examining excavated root systems of 20 mature trees. The root system was dominated by 6.1±1.3 lateral roots, more than 70% of the lateral root cross sectional area (CSA) being distributed in the uppermost 10 cm of soil. Anchorage strength was related to the size of the tree and CSA. The overturning moment of trees was proportional to the diameter at breast height (DBH) to the power of 1.6. The trees exhibited significant asymmetry in anchorage rigidity, but although there was clustering of lateral roots in a preferred direction the root asymmetry was not significantly correlated with the asymmetry in anchorage rigidity, suggesting that much of the anchorage is provided by tap and sinker roots, rather than the laterals. However, the major laterals showed dorsoventral eccentricity, the more eccentric ones being those that were distributed closer to the soil surface and which pointed perpendicular to the direction of greatest resistance. This suggests that this is a result of thigmomorphogenetic effects. These results are compared with those for the related P. sylvestris and suggest that the assimilation and anchorage characteristics of root systems are controlled independently of each other.
  • Mickovski, School of Biological Sciences, University of Manchester, 3.614 Stopford Building, Manchester M13 9PT, UK E-mail: sbm@nn.uk
  • Ennos, School of Biological Sciences, University of Manchester, 3.614 Stopford Building, Manchester M13 9PT, UK E-mail: roland.ennos@man.ac.uk (email)
article id 524, category Research article
Timo Pukkala, Jari Miina, Marc Palahí. (2002). Thinning response and thinning bias in a young Scots pine stand. Silva Fennica vol. 36 no. 4 article id 524. https://doi.org/10.14214/sf.524
Keywords: Pinus sylvestris; growth model; non-spatial model; spatial model
Abstract | View details | Full text in PDF | Author Info
The study analyses the annual post-thinning response and thinning bias of a young Scots pine stand as a function of tree size, competition faced by the tree, and competition that is removed around the tree in the thinning treatment. The thinning response of a tree was defined as the change of tree growth due to a thinning treatment. The thinning bias was defined as the difference between the true growth and model prediction. A distance-dependent (spatial) and a distance-independent (non-spatial) growth model were used in the calculations. The empirical data were measured from a thinning experiment consisting of ten plots, each 40 x 30 m in size, which were thinned to different stand densities. The ten-year post-thinning growth of every remaining tree was measured. The results indicated that the highest thinning response is among medium-sized and co-dominant trees. The thinning response is quite small, and even negative for some trees, for two years after thinning but it becomes clearly positive from the third year onwards. The spatial model underestimated the growth of small trees (which usually face high competition) while the non-spatial model overestimated the growth of trees that are small or face much competition. The spatial model used in this study overemphasized the effect of competition while the non-spatial model underestimated this effect. Both growth models overestimated the growth of trees in heavily thinned places, but this bias disappeared in two years. The negative bias was more pronounced with a spatial growth model because the tendency of the non-spatial model to underestimate the growth of trees facing little competition partly compensated for the negative bias.
  • Pukkala, University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland E-mail: timo.pukkala@joensuu.fi (email)
  • Miina, Finnish Forest Research Institute, Joensuu Research Centre, P.O. Box 68, FIN-80101 Joensuu, Finland E-mail: jm@nn.fi
  • Palahí, European Forest Institute, Torikatu 34, FIN-80100 Joensuu, Finland E-mail: mp@nn.fi
article id 519, category Research article
Magnus Lindén, Gudmund Vollbrecht. (2002). Sensitivity of Picea abies to butt rot in pure stands and in mixed stands with Pinus sylvestris in southern Sweden. Silva Fennica vol. 36 no. 4 article id 519. https://doi.org/10.14214/sf.519
Keywords: Pinus sylvestris; Norway spruce; Picea abies; logistic regression; Heterobasidion annosum; Butt rot; mixed forest
Abstract | View details | Full text in PDF | Author Info
Repeatedly sampled data from permanent experimental plots in southern Sweden were used to model butt rot development in Norway spruce growing in pure stands and in mixed stands with Scots pine. The data come from 29 sites with pure spruce, altogether 100 plots, and from 15 sites of mixed spruce and pine, altogether 22 plots. A logistic model provided the best fit to the data. The study material revealed that in mixed stands the proportion of spruce trees with butt rot is lower than in pure Norway spruce stands. The difference in the incidence of butt rot cannot be explained by silviculture or windthrow since both factors are accounted for in the study. The most significant effect on butt rot development in Norway spruce by an admixture of Scots pine, was found when the Scots pine admixture was 50%. In order to reduce the incidence of butt rot in Norway spruce, the study material indicate that there is little to be gained by increasing the Scots pine admixture to much more than 50%.
  • Lindén, Southern Swedish Forest Research Centre c/o Asa Experimental Forest, SLU, S-360 30 Lammhult, Sweden E-mail: magnus.linden@ess.slu.se (email)
  • Vollbrecht, Southern Swedish Forest Research Centre c/o Asa Experimental Forest, SLU, S-360 30 Lammhult, Sweden E-mail: gv@nn.se
article id 529, category Research article
Tuula Aalto, Pertti Hari, Timo Vesala. (2002). Comparison of an optimal stomatal regulation model and a biochemical model in explaining CO2 exchange in field conditions. Silva Fennica vol. 36 no. 3 article id 529. https://doi.org/10.14214/sf.529
Keywords: photosynthesis; Scots pine; optimization; Pinus sylvestris L.; CO2 exchange; biochemical model
Abstract | View details | Full text in PDF | Author Info
Gas exchange of Pinus sylvestris L. was studied in subarctic field conditions. Aspects on optimal control of the gas exchange were examined using approach by Hari et al. (Tree Phys. 2: 169–175, 1986). Biochemical model by Farquhar et al. (Planta 149: 78–90, 1980) was utilized to describe the photosynthetic production rate of needles. The model parameters were determined from field measurements. The results from the optimization approach and biochemical model were compared and their performance was found quite similar in terms of R2 calculated using measured exchange rates (0.89 for optimization model and 0.85 for biochemical model). Minor differences were found in relation to responses to intercellular carbon dioxide concentration and temperature.
  • Aalto, Finnish Meteorological Institute, Air Quality Research, Sahaajankatu 20 E, FIN-00810 Helsinki, Finland E-mail: tuula.aalto@fmi.fi (email)
  • Hari, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: ph@nn.fi
  • Vesala, University of Helsinki, Dept. of Physics, P.O. Box 64, FIN-00014 University of Helsinki, Finland E-mail: tv@nn.fi
article id 539, category Research article
Martti Venäläinen, Seppo Ruotsalainen. (2002). Procedure for managing large-scale progeny test data: a case study of Scots pine in Finland. Silva Fennica vol. 36 no. 2 article id 539. https://doi.org/10.14214/sf.539
Keywords: Pinus sylvestris; selection; progeny testing; performance level; reliability coefficient
Abstract | View details | Full text in PDF | Author Info
Large progeny test networks are typical for conventional forest tree breeding programmes. The individual progeny tests differ with respect to age, composition and ability to screen the breeding values of the parent trees. Several approaches have been introduced to manage the unbalanced and diverse nature of the data generated by progeny tests. This report presents a procedure for ranking breeding material on the basis of ‘messy’ data. Plot means were used as input values and missing plots were estimated from least squares. The differences between test means and variances were standardised by the performance level method. The different precision of the tests was quantified through the reliability coefficient. In order to facilitate the selection of plus trees for different purposes, all the available test results were combined into a single variable that was used for ranking. Three different kinds of ranking variable were calculated and each of them proved to be more useful for the selection of plus trees than an arithmetic or weighted mean. One of them, WMEAN, relied on the reliability and number of the progeny tests, while the others, WCONF0.50 and WCONF0.10, relied on the standard error of the plus tree mean, thus emphasising the precision of the values obtained. The analyses were carried out with SAS® procedures, which require only moderate skills in statistics, programming and data processing technology. The procedure has functioned well throughout an eight-year development phase. Nearly three thousand Scots pine (Pinus sylvestris) plus trees have been ranked for various characters, and the results have been used for roguing the seed orchards, to establish new ones, and to select plus trees for breeding populations.
  • Venäläinen, Finnish Forest Research Institute, Punkaharju Research Station, FIN-58450 Punkaharju, Finland E-mail: martti.venalainen@metla.fi (email)
  • Ruotsalainen, Finnish Forest Research Institute, Punkaharju Research Station, FIN-58450 Punkaharju, Finland E-mail: sr@nn.fi
article id 538, category Research article
Seppo Nevalainen. (2002). The incidence of Gremmeniella abietina in relation to topography in southern Finland. Silva Fennica vol. 36 no. 2 article id 538. https://doi.org/10.14214/sf.538
Keywords: Pinus sylvestris; forest inventory; Gremmeniella abietina; topography; digital elevation models
Abstract | View details | Full text in PDF | Author Info
Field data of the 8th National Forest Inventory (NFI) from southern Finland and digital elevation models (DEMs) were used in this study. Damage due to Gremmeniella abietina increased slightly with an increase in absolute elevation in mineral soils. Severe damage increased almost linearly with an increase in elevation in mineral soil plots. The mean elevation in the tract area (the 7 km x 8 km area surrounding the plot) was more strongly correlated with the disease than the elevation of individual plots. The relative altitude of the plot was important: the disease was most severe in the plots situated lower than the mean elevation of the tract area, especially in the peatland plots. In this group, the damage increased linearly with an increase in absolute elevation. According to detailed DEMs in the most diseased areas, steepness of the slope was negatively correlated with the disease. The aspect of the slope had a weak influence. On mineral soils, the disease was most common in south-facing slopes. The microtopography was not as important for the disease occurrence as the relative elevation of the plot. The disease frequencies were very similarly related to the three most common types of surface features (channels, ridges and planar regions) within the 50-m scale. At the cell size of 100 metres, the disease was more common in channels than in ridges, except in mineral soil plots. Topographic variables only partly explained the regional patterns in the occurrence of this disease. The disease was frequent on upland areas, but, on the other hand, it was also common on lowland areas. The most diseased areas studied in detail differed very much from each other with respect to topography and the disease incidence.
  • Nevalainen, Finnish Forest Research Institute, Joensuu Research Centre, P.O. Box 68, FIN-80101 Joensuu, Finland E-mail: seppo.nevalainen@metla.fi (email)
article id 537, category Research article
Timo Kurkela. (2002). Crown condition as an indicator of the incidence of root rot caused by Heterobasidion annosum in Scots pine stands. Silva Fennica vol. 36 no. 2 article id 537. https://doi.org/10.14214/sf.537
Keywords: Pinus sylvestris; Heterobasidion annosum; root rot; symptoms; disease incidence
Abstract | View details | Full text in PDF | Author Info
Trees in three Scots pine stands seriously infected by Heterobasidion annosum were classified according to their crown condition into four classes, from healthy to dead trees. After cutting the stands, the classification was compared with the symptoms of annosum root rot on stump surfaces (pitched area) and with the extension of decay in the roots of excavated stumps. When dead trees were included, the average crown condition on the survey plots correlated with disease incidence. Without dead trees the correlation was not significant. Slightly infected trees could not be distinguished from healthy trees on the basis of crown condition. It was concluded that only the proportion of dead and dying trees in a stand is a reliable indication of the disease incidence for making decisions about the future management.
  • Kurkela, Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: timo.kurkela@metla.fi (email)
article id 557, category Research article
Tuomo Wallenius, Timo Kuuluvainen, Raimo Heikkilä, Tapio Lindholm. (2002). Spatial tree age structure and fire history in two old-growth forests in eastern Fennoscandia. Silva Fennica vol. 36 no. 1 article id 557. https://doi.org/10.14214/sf.557
Keywords: Pinus sylvestris; Picea abies; disturbance dynamics; spatial autocorrelation; spatial pattern
Abstract | View details | Full text in PDF | Author Info
Two near natural old-growth forests, one dominated by Picea abies and the other by Pinus sylvestris, were studied for their fire history, and spatial patterns of trees and tree ages. The spatial tree age structure and the disturbance history of the forests were examined by drawing age class maps based on mapped and aged trees and by dating fires based on fire scars, and by using spatial analyses at tree scale. The tree age structures of the Picea and Pinus dominated forests were different, mainly due to differences in fire history and sensitivity of the dominant tree species to fire. Fire histories and tree age structures of both sites have probably been affected by human in the ancient past. However, in the Picea dominated site, the fires had been severe, killing most of the trees, whereas in the Pinus dominated site the severity of fires had been more variable, leaving some Pinus and even Picea trees alive. In the Pinus dominated site, the tree age distribution was multimodal, consisting of two Pinus cohorts, which were established after fires and a later Picea regeneration. The Picea dominated site was composed of four patches of different disturbance history. In the oldest patch, the tree age distribution was unimodal, with no distinct cohorts, while a single cohort that regenerated after severe fire disturbances dominated the three other patches. In both sites the overall spatial patterns of living and dead trees were random and the proportion of spatially autocorrelated variance of tree age was low. This means that trees of different age grew more or less mixed in the forest without forming spatially distinct regeneration patches, even in the oldest patch of Picea dominated Liimatanvaara, well over 200 years after a fire. The results show that detail knowledge of disturbance history is essential for understanding the development of tree age structures and their spatial patterns.
  • Wallenius, Department of Ecology and Systematics, University of Helsinki, P.O. Box 65, FIN-00014, Helsinki, Finland E-mail: tuomo.wallenius@helsinki.fi (email)
  • Kuuluvainen, Department of Forest Ecology, University of Helsinki, P.O. Box 27, FIN-00014, Helsinki, Finland E-mail: tk@nn.fi
  • Heikkilä, Research Centre of Friendship Park, Tönölä, FIN-88900 Kuhmo, Finland E-mail: rh@nn.fi
  • Lindholm, Finnish Environment Institute, Nature and Land Use Division, P.O. Box 140, FIN-00251 Helsinki, Finland E-mail: tl@nn.fi
article id 590, category Research article
Anna Saarsalmi, Eino Mälkönen, Sirpa Piirainen. (2001). Effects of wood ash fertilization on forest soil chemical properties. Silva Fennica vol. 35 no. 3 article id 590. https://doi.org/10.14214/sf.590
Keywords: Pinus sylvestris; wood ash; Picea abies; nutrients; acidity; neutralization; pH
Abstract | View details | Full text in PDF | Author Info
The effects of wood ash fertilization on soil chemical properties were studied in three young Scots pine (Pinus sylvestris L.) plantations and a Norway spruce (Picea abies (L.) Karst.) plantation with different site fertility in southern Finland. The dose of 3 t ha–1 of loose wood ash was applied to 4 replicate plots (25 x 25 m) at each experiment. Humus layer and mineral soil samples were taken before the treatment and 7 and 16 years after wood ash application. Results showed that neutralization as well as fertilization effects of wood ash on forest soil were of long duration. An ash-induced pH increase of 0.6–1.0 pH units and exchangeable acidity (EA) decrease of 58–83% were detected in the humus layer 16 years after wood ash application. The decrease in acidity was most pronounced on the Calluna site with initially the lowest pH and highest EA. In the mineral soil the increase in pH was observed later than in the humus layer. After 16 years, the mineral soil pH was increased (0.2–0.3 pH units) on the Vaccinium and Myrtillus sites. A corresponding and in most cases a significant increase in the extractable Ca and Mg concentrations was detected in both the humus layer and in the mineral soil. Wood ash significantly increased the effective cation exchange capacity (CECe) and base saturation (BS) but decreased the concentration of exchangeable Al in both soil layers on all the sites. No response of N availability to wood ash application could be found.
  • Saarsalmi, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: anna.saarsalmi@metla.fi (email)
  • Mälkönen, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: em@nn.fi
  • Piirainen, Finnish Forest Research Institute, Joensuu Research Station, P.O. Box 68, FIN-80101 Joensuu, Finland E-mail: sp@nn.fi
article id 617, category Research article
Jouni Siipilehto. (2000). A comparison of two parameter prediction methods for stand structure in Finland. Silva Fennica vol. 34 no. 4 article id 617. https://doi.org/10.14214/sf.617
Keywords: Pinus sylvestris; Picea abies; parameter prediction; dbh and height distribution; Johnson’s SBB distribution; Näslund’s height curve
Abstract | View details | Full text in PDF | Author Info
The objective of this paper was to predict a model for describing stand structure of tree heights (h) and diameters at breast height (dbh). The research material consisted of data collected from 64 stands of Norway spruce (Picea abies Karst.) and 91 stands of Scots pine (Pinus sylvestris L.) located in southern Finland. Both stand types contained birch (Betula pendula Roth and B. pubescent Ehrh.) admixtures. The traditional univariate approach (Model I) of using the dbh distribution (Johnson’s SB) together with a height curve (Näslund’s function) was compared against the bivariate approaches, Johnson’s SBB distribution (Model II) and Model Ie. In Model Ie within-dbh-class h-variation was included by transforming a normally distributed homogenous error of linearized Näslund’s function to concern real heights. Basal-area-weighted distributions were estimated using the maximum likelihood (ML) method. Species-specific prediction models were derived using linear regression analysis. The models were compared with Kolmogorov-Smirnov tests for marginal distributions, accuracy of stand variables and the dbh-h relationship of individual trees. The differences in the stand characteristics between the models were marginal. Model I gave a slightly better fit for spruce, but Model II was better for pine stands. The univariate Model I resulted in clearly too narrow marginal h-distribution for pine. It is recommended applying of a constrained ML method for reasonable dbh-h relationship instead of using a pure ML method when fitting the SBB model.
  • Siipilehto, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: jouni.siipilehto@metla.fi (email)
article id 641, category Research article
Juha Kaitera. (2000). Analysis of Cronartium flaccidum lesion development on pole-stage Scots pines. Silva Fennica vol. 34 no. 1 article id 641. https://doi.org/10.14214/sf.641
Keywords: Pinus sylvestris; aecia; Cronartium flaccidum; lesion; resin top
Abstract | View details | Full text in PDF | Author Info
Historical and current lesion development and sporulation of Cronartium flaccidum was investigated in a stand of artificially seeded pole-stage Pinus sylvestris in northern Finland. An average of 6.5 lesions developed per infected tree, most of them occurring on a minority (25%) of the trees. During the monitoring period of five years, fresh aecia appeared mainly in 7–10-year-old shoots, the age of the shoots bearing aecia varying between 3–20 years. Aecia appeared for the first time most frequently in 5–10-year-old shoots. Infection waves occurred, whereas lesions were formed most frequently in shoots formed in various years through the 1980s. After the lesions started to sporulate, sporulation in most lesions that finished sporulating during the monitoring period lasted for 1–2 years. The aecia in between 47% and 59% of the infected shoots developed annually over a longer length in proximal direction than in distal direction next to the previous year’s infection. The aecia-bearing distal part of the shoot was longer in between 19% and 37% of the shoots.
  • Kaitera, Finnish Forest Research Institute, Rovaniemi Research Station, P.O. Box 16, FIN-96301 Rovaniemi, Finland E-mail: juha.kaitera@metla.fi (email)
article id 647, category Research article
Tapio Linkosalo. (1999). Regularities and patterns in the spring phenology of some boreal trees. Silva Fennica vol. 33 no. 4 article id 647. https://doi.org/10.14214/sf.647
Keywords: Populus tremula; Pinus sylvestris; flowering; Alnus glutinosa; bud burst; Alnus incana; phenological regulation; phenological time series; Betula sp.
Abstract | View details | Full text in PDF | Author Info
Phenological time series of flowering and bud burst of Populus tremula (L.) and Betula sp., and the flowering of Pinus sylvestris (L.), Alnus glutinosa (L.) and Alnus incana (L.) were constructed from data collected in Finland during the period 1896–1955. The resulting combined time series were examined with two aims in mind: first, to determine the phenological regularities between different species and, second, to detect patterns of spring advancement over a geographically large area. The results indicate that the geographical pattern of spring advancement is rather uniform from year to year, and between different species. Furthermore, the mechanisms regulating the timing of phenological events in different species seem to function in a similar way, suggesting an unanimous optimal response to climatic conditions.
  • Linkosalo, University of Helsinki, Department of Forest Ecology, Unioninkatu 40 B, P.O. Box 24, FIN-00014 University of Helsinki, Finland E-mail: tapio.linkosalo@helsinki.fi (email)
article id 662, category Research article
Lars Björklund. (1999). Identifying heartwood-rich stands or stems of Pinus sylvestris by using inventory data. Silva Fennica vol. 33 no. 2 article id 662. https://doi.org/10.14214/sf.662
Keywords: Pinus sylvestris; sapwood; heartwood; wood utilisation
Abstract | View details | Full text in PDF | Author Info
Variations in heartwood percentage, heartwood radius and sapwood width, within and between stands of Scots pine (Pinus sylvestris L.), were analysed using a database of 198 CT-scanned (computer tomography) stems from 33 research plots (stands) throughout Sweden. Heartwood percentage varied greatly both between individual trees and between stands, and correlated poorly to site, stand and tree variables. This implies that it seems unfeasible to identify heartwood-rich stands or stems, e.g., for production of heartwood products, by using inventory data. Heartwood formation expressed as the number of new heartwood rings formed each year was found to increase with increasing cambial age, from about 0.5 rings per year at a cambial age of 45 years, to about 0.8 rings per year at a cambial age of 115 years.
  • Björklund, Swedish University of Agricultural Sciences, Department of Forest Management and Products, S-750 07 Uppsala, Sweden E-mail: lars.bjorklund@sh.slu.se (email)
article id 676, category Research article
Erik Sundström. (1998). Afforestation of low-productive peatlands in Sweden – a tree species comparison. Silva Fennica vol. 32 no. 4 article id 676. https://doi.org/10.14214/sf.676
Keywords: Pinus sylvestris; fertilization; Picea abies; afforestation; drainage; tree species; climate; Pinus contorta; broadcast fertilization; spot fertilization
Abstract | View details | Full text in PDF | Author Info
In 1970, five low-productive treeless peatlands in Sweden, ranging from latitudes 56°N to 67°N, were drained and fertilized for afforestation. The aim of the study was to determine the effect of four ditch spacings, varying from 7.5 to 60 m, and five NPK-fertilizer combinations, on the survival and growth of planted Scots pine (Pinus sylvestris), lodgepole pine (Pinus contorta), Norway spruce (Picea abies), and silver birch (Betula pendula) seedlings. The assessments were carried out 18–22 years after planting. Neither silver birch, nor Norway spruce was regarded suitable for the site type. The mortality of silver birch was almost complete, and Norway spruce did not grow well in any of the study areas, however, better than Scots pine in the north. Lodgepole pine had better height and diameter growth but also higher mortality rates than Scots pine. In the two northernmost experimental areas no response to fertilization was found. In the other three areas, the response to fertilization did not differ between species. Phosphorus was the most effective of the added fertilizer elements, whereas nitrogen showed no positive effect. Broadcast fertilizer application, with three times higher amount of fertilizer per ha gave the same growth response as spot application.
  • Sundström, Swedish University of Agricultural Sciences, Dept. of Silviculture, S-901 83 Umeå, Sweden E-mail: erik.sundstrom@ssko.slu.se (email)
article id 674, category Research article
Tuula Aalto. (1998). Carbon dioxide exchange of Scots pine shoots as estimated by a biochemical model and cuvette field measurements. Silva Fennica vol. 32 no. 4 article id 674. https://doi.org/10.14214/sf.674
Keywords: Pinus sylvestris; photosynthesis; Scots pine; CO2 exchange; cuvette measurements
Abstract | View details | Full text in PDF | Author Info
A biochemical model was used to calculate CO2 fluxes to Scots pine shoots in two boreal measurement stations, Hyytiälä in southern Finland (61°51’N, 24°17’E) and Värriö in northern Finland (67°46’N, 29°35’E). The results of the model were compared with cuvette measurements performed in field conditions. A differential equation for change in gas concentration inside a closed cuvette was constructed and solved in order to obtain conductances and fluxes. The results were generally in a good agreement, the correlation coefficients varied from 0.74 to 0.95. Some discrepancies were also found. The model followed more intensively changes in temperature. This could be seen in northern Finland measurements at low temperatures (< 18 °C). The modelled temperature response indicated low fluxes at low temperatures, but measurements did not show any decrease. The irradiation response was relatively similar in both measuring sites and according to the model. Cuvette measurements showed slightly smaller quantum yields as a result from shading of the needles. The temperature dependences of the biochemical model parameters Jmax and Vc(max) were re-evaluated from the field measurements. The results for Vc(max) agreed well with earlier estimations, while the results for Jmax indicated relatively high values at low temperatures especially in northern Finland. Exponential fitting produced also substomatal concentrations of CO2, which agreed quite well with the model. The daily minimum of substomatal/ambient concentration ratio varied from 0.4 to 0.8.
  • Aalto, Department of Physics, P.O. Box 9, FIN-00014 University of Helsinki, Finland E-mail: tuula.aalto@helsinki.fi (email)
article id 681, category Research article
Virpi Palomäki, Alpo Hassinen, Matti Lemettinen, Timo Oksanen, Heljä-Sisko Helmisaari, Jarmo Holopainen, Seppo Kellomäki, Toini Holopainen. (1998). Open-top chamber fumigation system for exposure of field grown Pinus sylvestris to elevated carbon dioxide and ozone concentration. Silva Fennica vol. 32 no. 3 article id 681. https://doi.org/10.14214/sf.681
Keywords: Pinus sylvestris; CO2; open-top chamber; O3
Abstract | View details | Full text in PDF | Author Info
An open-top chamber fumigation system was built in a young Scots pine stand to study the effects of realistic elevated ozone (O3) and carbon dioxide (CO2) concentrations and their combination on trees in natural conditions. Doubled CO2 concentration compared to present ambient concentration, and O3 concentration between 40 ppb and 70 ppb in the first study year (1994) and doubled O3 concentration in years 1995 and 1996 were the target concentrations in the chambers. The O3 concentration in the chambers was successfully maintained close to the target concentration and differences between chambers were small. The mean CO2 concentration in the CO2 treatment was ca. 100 ppm below the target, but was maintained at this level throughout the growing season. Two degrees higher mean air temperature and slightly lower light intensity compared to open air were measured in the chambers. The operation of the fumigation system was satisfactory during the three study years and repeatability of the gas treatments can be regarded good in this low cost exposure system.
  • Palomäki, University of Kuopio, Department of Ecology and Environmental Science, P.O.Box 1627, FIN-70211 Kuopio, Finland E-mail: virpi.palomaki@uku.fi (email)
  • Hassinen, Mekrijärvi Research Station, FIN-82900 Ilomantsi, Finland E-mail: ah@nn.fi
  • Lemettinen, Mekrijärvi Research Station, FIN-82900 Ilomantsi, Finland E-mail: ml@nn.fi
  • Oksanen, University of Kuopio, Department of Ecology and Environmental Science, P.O.Box 1627, FIN-70211 Kuopio, Finland E-mail: to@nn.fi
  • Helmisaari, Finnish Forest Research Institute, Department of Forest Ecology, P.O.Box 18, FIN-01301 Vantaa, Finland E-mail: hsh@nn.fi
  • Holopainen, Agricultural Research Centre, FIN-31600 Jokioinen, Finland E-mail: jh@nn.fi
  • Kellomäki, University of Joensuu, Faculty of Forestry, P.O.Box 111, FIN-80101 Joensuu, Finland E-mail: sk@nn.fi
  • Holopainen, University of Kuopio, Department of Ecology and Environmental Science, P.O.Box 1627, FIN-70211 Kuopio, Finland E-mail: th@nn.fi
article id 691, category Research article
Jacek Oleksyn, Mark G. Tjoelker, Peter B. Reich. (1998). Adaptation to changing environment in Scots pine populations across a latitudinal gradient. Silva Fennica vol. 32 no. 2 article id 691. https://doi.org/10.14214/sf.691
Keywords: Pinus sylvestris; climate change; provenance; growth; temperature; photoperiod
Abstract | View details | Full text in PDF | Author Info
In several growth chamber and field experiments we examined the growth response of Scots pine (Pinus sylvestris L.) populations from a wide latitudinal range to temperature and photoperiod. The duration of the shoot elongation period of one-year-old seedlings was affected by temperature and photoperiod. In contrasting temperatures, 23/20 °C, 20/17 °C, and 17/14 °C (day/night), shoot elongation period for all populations was shortest in the high and longest in the low temperature treatments. The northern populations from 61–57°N ceased height growth earlier than the other populations in the southern 50°N photoperiod. The order of growth cessation among populations at 50°N in the chamber experiment and at 52°N in the field experiment was similar and related to observed population differences in terminal leader growth and total tree height. Since the length of growing season is under strong environmentally-mediated genetic control in Scots pine, potential climatic changes such as increasing temperature will probably alter the length and timing of growth in aboveground tree parts, but likely in the opposite direction (a shorter growing season) than has been often hypothesized (a longer growing season). Tree-ring analyses of a provenance experiment established in 1912 indicate that the main climatic factors that limited ring-width growth in Scots pine were air temperatures in the winter months of December through March. Low winter temperatures were followed by the formation of narrow rings over the next summer. Based on responses to temperature, Scots pine populations from the continuous European range can be divided in several geographic groups along a latitudinal gradient. Our results suggest that in developing new models to predict the response of Scots pine to changing environmental conditions, it is necessary to include intraspecific differentiation in acclimation and adaptation to environmental factors.
  • Oleksyn, Polish Academy of Sciences, Institute of Dendrology, Parkowa 5, PL-62-035 Kórnik, Poland; University of Minnesota, Department of Forest Resources, 1530 Cleveland Ave. N., St. Paul, MN 55108, USA E-mail: oleks001@gold.tc.umn.edu (email)
  • Tjoelker, University of Minnesota, Department of Forest Resources, 1530 Cleveland Ave. N., St. Paul, MN 55108, USA E-mail: mgt@nn.us
  • Reich, University of Minnesota, Department of Forest Resources, 1530 Cleveland Ave. N., St. Paul, MN 55108, USA E-mail: pbr@nn.us
article id 690, category Research article
Bengt Persson. (1998). Will climate change affect the optimal choice of Pinus sylvestris provenances? Silva Fennica vol. 32 no. 2 article id 690. https://doi.org/10.14214/sf.690
Keywords: Pinus sylvestris; yield; survival; temperature sum; climatic warming; provenance transfer
Abstract | View details | Full text in PDF | Author Info
Provenance experiments with Pinus sylvestris (L.) were evaluated in Sweden north of latitude 60°N. Survival and yield were determined as functions of temperature sum of the site and latitudinal origin of the provenance. Altitudinal origin was of negligible importance. The effects of latitudinal transfer were influenced by temperature sum at the growing site. At the harshest situated sites southward transfer longer than 3° was optimal for survival and yield, whereas transfer effects in a mild climate were weak. Climatic warming would reduce demands of hardiness. However, moderate differences in productivity are expected between formerly optimal seed sources and the ones adapted to changed climatic conditions. Since mortality usually was low in plantations older than 20 years or higher than 2 m, established stands are expected to be robust against adverse effects of climate change.
  • Persson, Högskolan Dalarna, S-781 88 Borlänge, Sweden E-mail: bpn@du.se (email)

Category : Review article

article id 694, category Review article
Gösta Eriksson. (1998). Evolutionary forces influencing variation among populations of Pinus sylvestris. Silva Fennica vol. 32 no. 2 article id 694. https://doi.org/10.14214/sf.694
Keywords: Pinus sylvestris; Scots pine; among-population variation; evolutionary forces
Abstract | View details | Full text in PDF | Author Info
The evolutionary forces influencing genetic differentiation among populations are identified. Natural selection, random genetic drift, and mutations promote differentiation while phenotypic plasticity and gene flow delay or prevent differentiation. Evolution is a dynamic force which leads to instability and absence of any perfection in the adaptive process. Natural selection acts mainly on phenotypes and only indirectly on the components of important breeding traits. In the northern part of the distribution of Scots pine there is a large among- and within-population variation in survival. The high among-population variation occurs in spite of an assumed high gene flow. Biomass is a product of many components and it also shows a high population variation. Many markers are neutral and such markers will not reveal adaptive variation.
  • Eriksson, Swedish University of Agricultural Sciences, Department of Forest Genetics, Uppsala, Sweden E-mail: gosta.eriksson@sgen.slu.se (email)
article id 693, category Review article
Erik G. Ståhl. (1998). Changes in wood and stem properties of Pinus sylvestris caused by provenance transfer. Silva Fennica vol. 32 no. 2 article id 693. https://doi.org/10.14214/sf.693
Keywords: Pinus sylvestris; yield; silviculture; provenance; wood properties; growth phenology
Abstract | View details | Full text in PDF | Author Info
Wood properties focused in forest tree breeding should be of economic importance, have a large total variation and a high heritability. The properties of interest are those that influence the strength and durability of sawn products or the amount and properties of pulp produced. The following wood properties are treated: width of the annual ring, juvenile wood, late wood content, heart wood, tracheid dimensions, basic density, stem straightness and branch diameter. The provenance variation in wood properties can be related to differences in growth phenology. In the northern part of distribution P. sylvestris (L.) provenances transferred a few degrees southwards have a high survival and yield but stem wood production is low. Trees from these provenances will be straight and with few spike knots or other injuries. The shoot elongation period will be short and the temperature sum required for wood formation sufficient. Provenances transferred southwards will form thin annual rings, few and thin branches, little early wood, high basic density and slender tracheids with thick cell walls in comparison to local provenances. An example of the effect of alternative transfers on the yield and wood properties is evaluated. In regions with deviating climatic patterns alternative provenance transfer patterns may be better. The objectives of the land owner should influence the provenance choice. The importance of integrating tree improvement with silvicultural management is discussed with reference to spacing.
  • Ståhl, College of Dalarna, CITU Centre for Industrial Technology and Development, S-781 88 Borlänge, Sweden E-mail: esl@du.se (email)

Category : Research note

article id 22008, category Research note
Eeva Terhonen. (2023). First report of Diplodia tip blight on Scots pine in Finland. Silva Fennica vol. 56 no. 4 article id 22008. https://doi.org/10.14214/sf.22008
Keywords: Pinus sylvestris; drought; Diplodia sapinea; Sphaeropsis sapinea; emerging fungal disease
Highlights: Diplodia tip blight is a new disease on Scots pine in Finland; Diplodia sapinea can be identified reliably with the presented pipeline.
Abstract | Full text in HTML | Full text in PDF | Author Info
Diplodia sapinea (Fr.) Fuckel causes shoot blight on Scots pine (Pinus sylvestris L.). This fungus has been discovered in Finland as a saprophyte in 2015 on Scots pine cones. The endophytic mode of this fungus was later discovered in healthy Scots pine twigs. In 2021 the disease, Diplodia tip blight was observed on Scots pine in Finland. Currently, the disease symptoms are poorly identified so the role of D. sapinea in disease outbreaks in Finland are easily overlooked. The identification of the fungi is challenging in field conditions and requires targeted identification in laboratory. In this research note I report the first Diplodia tip blight outbreaks observed in Finland, the typical disease symptoms, and methodology for the species identification. Samples were collected from symptomatic trees based on observations made by the citizens. Diplodia sapinea was isolated from defoliated and surface sterilized twigs. The species identification by morphological characters was further confirmed with sequencing of ITS region of rDNA and with species-specific primers. A pathogenicity test confirmed that D. sapinea was the disease agent causing shoot blight. This is the first report of Diplodia tip blight on Scots pine in Finland.
  • Terhonen, Natural Resources Institute Finland (Luke), Forest health and biodiversity, Latokartanonkaari 9, FI‐00790 Helsinki, Finland ORCID 0000-0002-9288-440X E-mail: eeva.terhonen@luke.fi
article id 10263, category Research note
Paul N. Katjutin, Natalia I. Stavrova, Vadim V. Gorshkov, Andrew Yu. Lyanguzov, Irina Ju. Bakkal, Sergey A. Mikhailov. (2020). Radial growth of trees differing in their vitality in the middle-aged Scots pine forests in the Kola peninsula. Silva Fennica vol. 54 no. 3 article id 10263. https://doi.org/10.14214/sf.10263
Keywords: Pinus sylvestris; northern taiga; radial increment; basal area increment
Highlights: Unmanaged middle-aged boreal Scots pine forests in the Kola peninsula are characterised by the prevalence of moderately and strongly weakened trees (65–70%); Radial increment and basal area increment differ greatly (70–75% and 85–90%, respectively) between Scots pine trees differing in their vitality; The trends of annual ring width in Scots pine trees aged from 15–35 to 65–85 years in green moss and green moss-lichen type pine forests are similar; the dynamics of basal area increment differs substantially in relation to forest site type.
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The research was carried out in unmanaged middle-aged (75–85 years) Northern taiga Scots pine (Pinus sylvestris L.) forests in the Kola peninsula. It was established that forests of green moss-lichen and green moss site types are characterised by a predominance (65–70% by stand volume) of moderately and strongly weakened trees. Trees of differing vitality have significant differences in annual increment. Healthy trees had a radial increment (RI) 70–75% greater than that of dying trees, and a basal area increment (BAI) 85–90% greater. The dynamics of the RI and BAI of Scots pine trees for the 70-year period (from 1945 to 2015) is different. The RI of all individuals in the communities studied decreases consistently. The decrease is expressed more strongly in green moss Scots pine forests (80–95% from 1945 to 2015) compared to green moss-lichen forests (60–80%); it manifests itself more in strongly weakened and dying individuals (75–95%) than in healthy and moderately weakened ones (60–80%). Annual basal area increment in green moss Scots pine forests increases by 45–65% from stand establishment until the trees are 25 to 35 years old and subsequently decreases by 50–80% to 70–80 years of age. In green moss-lichen pine forests the BAI of Scots pine remains rather stable in healthy and moderately weakened trees and decreases in strongly weakened and dying individuals by 45% and 75–80%, respectively throughout the studied period.

  • Katjutin, Komarov Botanical Institute of the Russian Academy of Sciences, Professora Popova str. 2, 197376, Saint-Petersburg, Russia E-mail: paurussia@binran.ru (email)
  • Stavrova, Komarov Botanical Institute of the Russian Academy of Sciences, Professora Popova str. 2, 197376, Saint-Petersburg, Russia E-mail: nstavrova@binran.ru
  • Gorshkov, Komarov Botanical Institute of the Russian Academy of Sciences, Professora Popova str. 2, 197376, Saint-Petersburg, Russia; Saint-Petersburg State Forest Technical University, letter U, 5, Institutsky per., 194021, Saint-Petersburg, Russia E-mail: vgorshkov@binran.ru
  • Lyanguzov, Saint-Petersburg State University, 7/9 Universitetskaya Emb., 199034, Saint-Petersburg, Russia E-mail: andrewlyanguzov@gmail.com
  • Bakkal, Komarov Botanical Institute of the Russian Academy of Sciences, Professora Popova str. 2, 197376, Saint-Petersburg, Russia E-mail: bakkal@binran.ru
  • Mikhailov, Komarov Botanical Institute of the Russian Academy of Sciences, Professora Popova str. 2, 197376, Saint-Petersburg, Russia E-mail: smikhailov@binran.ru
article id 1661, category Research note
Āris Jansons, Linda Robalte, Roberts Čakšs, Roberts Matisons. (2016). Long-term effect of whole tree biomass harvesting on ground cover vegetation in a dry Scots pine stand. Silva Fennica vol. 50 no. 5 article id 1661. https://doi.org/10.14214/sf.1661
Keywords: Pinus sylvestris; soil disturbance; stand replacement; Latvia; biomass removal; soil scarification
Highlights: After 47 years, whole tree harvesting (WTH) increased richness of ground cover species compared to conventionally managed stands; Higher occurrence of the oligotrophic species after WTH suggested reduction of soil nutrient content, hence formation of different plant community; WTH, apparently, facilitated recovery of species typical for later successional stages.
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Long-term (47 years) effect of experimental whole tree harvesting (WTH) with a heavy soil scarification on ground cover vegetation was assessed in a dry nutrient-poor Scots pine (Pinus sylvestris L.) stand in Latvia. Neighbouring conventionally managed young (10 years) and mature (119 years) stands of the same type were used for comparison. Higher species richness was observed in the WTH stand compared to conventionally managed young and mature stands (24, 18 and 16 species, respectively), likely due to the profound disturbance. The Shannon diversity index was higher in the young than in the WTH and mature stands (2.36, 1.77 and 1.63, respectively); still, the composition and structure of ground cover vegetation in WTH was more similar to the mature stand. Nevertheless, the occurrence of oligotrophic species in the WTH stand suggested decreased soil nutrient content and potential development of different plant community. Hence, such method might be considered for restoration of oligotrophic stands. Nevertheless, the period of 47 years appeared sufficient for the ground cover vegetation to recover after the WTH.

  • Jansons, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: aris.jansons@silava.lv
  • Robalte, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: robalte.l@gmail.com (email)
  • Čakšs, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: chakijs95@gmail.com
  • Matisons, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: roberts.matisons@silava.lv
article id 1330, category Research note
Hanne K. Sjølie, Hans Asbjørn Kårstad Sørlie, Bjørn Tveite, Birger Solberg. (2015). The performance of two Swedish N fertilization functions evaluated on data from Norwegian fertilization experiments. Silva Fennica vol. 49 no. 4 article id 1330. https://doi.org/10.14214/sf.1330
Keywords: Pinus sylvestris; Picea abies; forest production; forest fertilization; predictive functions
Highlights: The performance of two predictive Swedish fertilization growth response functions was assessed on data from Norwegian fertilization experiments; One function performed well on the full dataset, but overpredicted the growth response in spruce plots and underpredicted in pine plots; The second function performed well in pine stands, but overestimated the growth response in spruce and in total.
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This study compares the responses of two Swedish 5-year predictive stand-level functions with the observed responses in 721 fertilization experiment plots in Norway fertilized with nitrogen (N). All plots are single-species consisting of Norway spruce (Picea abies (L.) H. Karst.) or Scots pine (Pinus sylvestris L.) fertilized with ammonium nitrate (AN) or urea. The correlations between the observed and the two predicted responses were 0.34–0.40 for all plots taken together. One response function performed well on average, but underestimated the response in pine plots and overestimated the response in spruce plots. The second function overpredicted the response on the full dataset, in spruce plots and old forest, but performed well in pine plots. Both functions overestimated the growth response in high-productive plots. Higher N deposition in Norway than in Sweden may count for parts of the deviations. Testing of fertilization functions on new datasets is rare, but important part of the evaluation of functions. As the functions are not well fit for predicting the growth response in spruce and high-productive plots in our sample, new functions that include N deposition are welcome.

  • Sjølie, Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway E-mail: hanne.sjolie@nmbu.no (email)
  • Sørlie, Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway E-mail: hans.asbjorn.sorlie@slf.dep.no
  • Tveite, Norwegian Forest and Landscape Institute, P.O. Box 115, NO-1431 Ås, Norway E-mail: bjorn.tveite@skogoglandskap.no
  • Solberg, Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway E-mail: birger.solberg@nmbu.no
article id 402, category Research note
Miina Rautiainen, Pauline Stenberg, Tiit Nilson. (2005). Estimating canopy cover in Scots pine stands. Silva Fennica vol. 39 no. 1 article id 402. https://doi.org/10.14214/sf.402
Keywords: Pinus sylvestris; Cajanus tube; LAI-2000 Plant Canopy Analyzer
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The way canopy cover is defined and measured influences the obtained canopy cover percentage. Estimates of canopy cover are needed, for example, in canopy radiation modelling and remote sensing applications and as a tool for political decision-making. In this paper, we demonstrated the use of two methods, the LAI-2000 Plant Canopy Analyzer instrument and the Cajanus tube, in Scots pine stands for canopy cover estimation, and also assessed the number of measurement points required for reliable estimates. The Cajanus tube yielded slightly larger canopy closure values than the LAI-2000 instrument, but the values were nevertheless in good agreement. Both of the methods required approximately 250 measurement points for canopy closure estimates of a stand to become relatively stable. We also present the first measured effective canopy transmittance values for Scots pine stands in Finland and an example of tree pattern mapping with the Cajanus tube.
  • Rautiainen, Department of Forest Ecology, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: miina.rautiainen@helsinki.fi (email)
  • Stenberg, Department of Forest Ecology, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: ps@nn.fi
  • Nilson, Tartu Observatory, EE-61602 Tõravere, Tartumaa, Estonia E-mail: tn@nn.ee
article id 679, category Research note
Hans-Örjan Nohrstedt, Gunnar Börjesson. (1998). Respiration in a forest soil 27 years after fertilization with different doses of urea. Silva Fennica vol. 32 no. 4 article id 679. https://doi.org/10.14214/sf.679
Keywords: mineral soil; Pinus sylvestris L.; carbon mineralization; humus; podzol
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A number of previous studies have shown that N fertilization often reduces respiration in forest soils. However, the durability of this effect has not been fully explored. In this study, the response of soil respiration to a single fertilization with urea, applied 27 years earlier, was examined in a field experiment located in a stand of Pinus sylvestris in central Sweden. The doses that had been added were 120, 240 and 600 kg N ha–1. Samples were taken from the humus layer and the upper 7.5 cm of the mineral soil. Sieved samples were incubated in the laboratory. No effect of the previous fertilization on soil respiration was found, thus indicating that the reduction shown in earlier studies is not persistent. There was a tendency that the highest N dose had caused a higher N concentration and a lower C/N-ratio in the humus layer and a higher C concentration in the mineral soil.
  • Nohrstedt, The Forestry Research Institute of Sweden, Uppsala Science Park, S-751 83 Uppsala, Sweden E-mail: hans-orjan.nohrstedt@skogforsk.se (email)
  • Börjesson, Department of Microbiology, Swedish University of Agricultural Sciences, P.O. Box 7025, S-750 07 Uppsala, Sweden E-mail: gb@nn.se
article id 702, category Research note
Timo Kurkela, Heikki Nuorteva. (1998). Short-needle disease of Scots pine: an abnormal needle length distribution. Silva Fennica vol. 32 no. 1 article id 702. https://doi.org/10.14214/sf.702
Keywords: Pinus sylvestris; Scots pine; needle length; insect feeding; tissue deformation
Abstract | View details | Full text in PDF | Author Info
Short-needle syndrome occurs commonly in southern Finland. The disease is characterized by abnormal length distribution of the needles in shoots. In most cases, affected shoots have needles of normal length as well as very short needles. The short needles are those injured during the needle elongation period; the tissues formed abnormal sclerenchymatic structures and wound periderm. One possible cause could be hemipterous insects feeding on growing needles. Salivary sheaths of such insects were often present in both deformed needle bases and undeformed mature tissues.
  • Kurkela, Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: timo.kurkela@metla.fi (email)
  • Nuorteva, Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: hn@nn.fi

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