Articles containing the keyword 'mänty'

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
• Ikonen, E-mail: vi@mm.unknown
• Vanninen, E-mail: pv@mm.unknown

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
• Raitio, E-mail: hr@mm.unknown

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
• Kellomäki, E-mail: sk@mm.unknown
• Oker-Blom, E-mail: po@mm.unknown

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

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

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

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

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

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

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

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

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

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
• Nepveu, E-mail: gn@mm.unknown

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

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

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

Variation of monoterpene composition of Pinus sylvestris L. was studied in Southern, Central and Northern Finland using data from both natural stands and plus trees. The natural stands were analysed using different techniques and for fewer terpenes than the plus trees.

There were large differences between areas in the proportion of 3-carene in trees from natural stands, as has been discussed by previous authors. The proportion of 3-carene is bimodally distributed and believed to be controlled by a single gene with large effect. For this reason, we stratified our samples into high carene (>10%) and low carene (<10%) groups. Univariate analysis did not reveal any additional differences between natural populations in different zones for components other than 3-carene. In plus trees, several components showed significant differences, but the proportion of 3-carene did not differ between areas. Multivariate discrimination analysis did not distinguish between areas for natural stands. However, for the plus trees discriminant analysis allowed us to discriminate between the zones relatively efficiently. The proportion of correct classification was greater than 64% using the best methods. The central zone was most distinct, and 80% of its trees were correctly classified. Broad generalizations are not possible due to the limitations imposed by our data. Our analysis of phenotypic variation does not support the suggestion that plus trees selected from the north represent a southern type.

The PDF includes an abstract in Finnish.

• Muona, E-mail: om@mm.unknown
• Hiltunen, E-mail: rh@mm.unknown
• Morén, E-mail: em@mm.unknown
• Shaw, E-mail: ds@mm.unknown

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
• Pietilä, E-mail: jp@mm.unknown
• Vihola, E-mail: rv@mm.unknown

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

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
• Halinen, E-mail: mh@mm.unknown

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
• Pohjola, E-mail: tp@mm.unknown

Variation in tracheid morphology were examined for the bole wood of lodgepole pine (Pinus contorta Douglas ex Loudon) grown in Southern and Central Finland. Tracheid lengths were examined in a fast-grown and in slow-grown trees from three stands. Tracheid length increased with increasing height to 4–8 metres and decreased after that, and increased also with increasing age from the pith. The variation between stems was high. The shortest tracheids were about 1.11 mm near the piths and the longest about 4.10 mm near the bark.

Tracheid diameter and cell wall thickness were measured for the total number of 16 stems from Southern and Central Finland. Tracheid diameter increased with increasing distance from pith and the largest tracheids were at a height of 4–8 metres. Cell wall thickness varied independently of height in the stem. Summerwood cell wall thickness was twice that of springwood. There was a difference of 0.6 μm in springwood and 1.0 μm in summerwood double cell wall thickness between the two stands. Cell wall percentage was 29±4.7 in springwood and 69±7.3 in summerwood.

The PDF includes a summary in English.

• Saranpää, E-mail: ps@mm.unknown

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

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

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

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
• Laine, E-mail: jl@mm.unknown
• Lepola, E-mail: jl@mm.unknown

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
• Kellomäki, E-mail: sk@mm.unknown

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
• Pohjola, E-mail: tp@mm.unknown

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

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
• Aro-Heinilä, E-mail: va@mm.unknown
• Kellomäki, E-mail: sk@mm.unknown

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

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
• Kellomäki, E-mail: sk@mm.unknown

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
• Kostamo, E-mail: jk@mm.unknown
• Räsänen, E-mail: pr@mm.unknown

On the basis of a limited material, the drying of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) timber at room temperature decreased the thickness of the bark proportionally to the decrease in the moisture content. The decrease was the greatest in the middle portion of the trunk. In the spruce material, the decrease in bark thickness was exceeded by the shrinkage of the wood. During soaking, the bark thickness of both tree species decreased, too, contrary to the presupposed hypothesis. In both cases, the shrinkage was the greatest in the middle portion of the trunk. In the spruce material, the decrease in bark thickness was exceeded by the shrinkage of the wood. Possible explanation for the phenomenon is discussed.

The PDF includes a summary in English.

• Kellomäki, E-mail: sk@mm.unknown

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

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

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

In this study the loose volume of 58 piles of pulpwood were measured before and after barking by rotary ring barker. The volume was 2,121 m³. A recommendation is made, based on the results of the study, concerning the barking loss from piled wood: for green Scots pine (Pinus sylvestris L.) pulpwood, 8.8% of the stacked volume; for seasoned pine pulpwood, 6.1% of the stacked volume; and 8.0% for birch (Betula sp.) pulpwood, green and seasoned. The amount of bark left on bolts was small for pine bolts, namely 0.33%, but quite large for birch bolts, 2.84% of the green weight.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

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.

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• Enivaara, E-mail: ae@mm.unknown

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.

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• Selander, E-mail: js@mm.unknown
• Kalo, E-mail: pk@mm.unknown

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
• Saikku, E-mail: os@mm.unknown

The study is the first report of a larger project concerning fire ecology in the Finnish boreal forests. Modern forestry has never been practiced in the Ulvinsalo strict nature reserve (2,500 ha) in Northern Finland in the county of Kuhmo. Forest fires have been uncommon because of mosaic of mineral and peat soils. The forests are mostly Norway spruce (Picea abies (L.) H. Karst.) dominated with Scots pine (Pinus sylvestris L.) often as the oldest trees of a stand. Forest fires were dated by counting annual rings from cambium to the fire scar in pines. 73 stands covering 1,207 ha were surveyed, over 80% of which was on mineral soil.

50% of the area had burned at least once during the life time of the present pine trees. 48 different forest fires were found, the first being from the year 1712 and the latest from 1969. The average time elapsed between the fires was about 82±43 years, and range 18–219 years. It was assumed that the stands where no fire scars were found, had, however, regenerated after fires but no fires have occurred since after that. In latter part of the 19th century 21 forest fires were dated, in the other half centuries only 4–9. This may have been caused by the increased human activity in the late 1800’s. The fire rotation of the area is 280 years, and spruce is almost the only tree species, which can regenerate in the present situation.

The PDF includes a summary in English.

• Haapanen, E-mail: ah@mm.unknown
• Siitonen, E-mail: ps@mm.unknown

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

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

A method is presented in this study for calculating the basic density of whole tree- and logging residue chips and the results of trial measurements on some commonly used chip sorts. The basic density of Scots pine whole tree chips was found to be 1–18 kg/m³ smaller than that of pine pulpwood of the same age. The basic density of Norway spruce whole tree chips was 4–22 kg/m³ greater than that of similar aged pulpwood. The basic density of birch whole tree chips was 4–16 kg/m³ and grey alder whole tree chips 7–24 kg/m³ greater than pulpwood of the same age. The basic density of conifer logging residue chips was considerably greater than that of pine and spruce whole tree ships.

The PDF includes a summary in English.

• Mäkelä, E-mail: mm@mm.unknown

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.

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• Lehtiniemi, E-mail: tl@mm.unknown

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
• Seppälä, E-mail: ks@mm.unknown

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

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.

The PDF includes a summary in English.

• Westman, E-mail: cw@mm.unknown

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
• Kellomäki, E-mail: sk@mm.unknown
• Westman, E-mail: cw@mm.unknown

In the study the proportion of branch samples of various diameter were studied. The branches were taken from small trees to be harvested by total tree chipping method. The material consisted of 1,056 branch samples of birch (Betula verrucosa, now B. pendula Roth, and Betula pubescens Erhr.), Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) at intervals of 20 cm along each branch.

With exception of the basic density of bark, there was a relation between all the other properties which were studied and the diameter. Even when the effect of diameter was eliminated, in many cases the effect of the distance of the samples from the stem became apparent.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

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.

The PDF includes a summary in English.

• Lehtonen, E-mail: il@mm.unknown
• Kellomäki, E-mail: sk@mm.unknown
• Westman, E-mail: cw@mm.unknown

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
• Smolander, E-mail: hs@mm.unknown

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.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

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.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

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

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

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.

The PDF includes a summary in English.

• Päivänen, E-mail: jp@mm.unknown

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.

The PDF includes a summary in English.

• Kupila-Ahvenniemi, E-mail: sk@mm.unknown
• Hankonen, E-mail: sh@mm.unknown
• Sivonen, E-mail: ss@mm.unknown

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

The paper describes a preliminary attempt to assess the long-term effect of urea application on the quantity of nitrogen available for plants in forest soil. The soil samples required for the study were collected from an experimental area which had been set up for investigations into both the single and joint effect on tree growth of two levels of each of urea and phosphorus application. The stand was a mixed forest of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) on Myrtillus type site with an average volume of 217.5 m³/ha.

According to the results, the nitrogen available for plants of the humus layer was significantly higher in fertilized than in unfertilized plots as late as four years after application. In terms of absolute values, the quantities were extremely small, only 3–4% of the amounts applied. In comparison with these results it was interesting to notice that urea application seemed to increase the C/N ratio.

The PDF includes a summary in English.

• Westman, E-mail: cw@mm.unknown

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.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

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.

The PDF includes a summary in English.

• Chudnyi, E-mail: ac@mm.unknown

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

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

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.

The PDF includes a summary in English.

• Päivänen, E-mail: jp@mm.unknown

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%.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

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

The study deals with the variation in the proportion of heartwood  in Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) both within and between stems as examined on the basis of literature. Special attention is paid to an application, in which on the basis of the diameter of pulpwood bolts, efforts are made to predict the proportion of heartwood in the total volume of bolts. It is shown that the method, even when based on homogenous material of 564 Norway spruce and Scots pine bolts, easily leads to wrong conclusions concerning the proportion of heartwood.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

Experimental applications of the nuclear polyhedrosis virus (Borrelinavirus diprionis) to control of the European pine sawfly (Neodiprion sertifer Geoff.) was carried out during the last outbreak of this sawfly in in Scots pine (Pinus sylvestris L.) in Finland in 1963. Quantities of polyhedrosis virus preparation, collected and purified in Finland were available as concentrations packed in capsules. Spraying took place in three localities in southwestern Finland when the larvae were in I–III instars.

When Finnish and Swedish preparations were used 83–96% of larval colonies were completely destroyed within 14 days. In addition, an attempt was made to change the virus in latent stage, present already in the area, to acute stage by application of substrates which are probably harmless to pine, but were expected to stress the larvae. Ground quarts as spray had the best lethal effect upon larvae.

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• Nuorteva, E-mail: mn@mm.unknown

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.

The PDF includes a summary in English.

• Oskarsson, E-mail: oo@mm.unknown
• Tigerstedt, E-mail: pt@mm.unknown

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

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
• Saramäki, E-mail: js@mm.unknown

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

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

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

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
• Räsänen, E-mail: pr@mm.unknown
• Yli-Vakkuri, E-mail: py@mm.unknown

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
• Hänninen, E-mail: th@mm.unknown

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
• Hiltunen, E-mail: mh@mm.unknown

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

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

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

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
• Räsänen, E-mail: pr@mm.unknown

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

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

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
• Ouni, E-mail: jo@mm.unknown

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%.

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• Tigerstedt, E-mail: pt@mm.unknown
• Malmivaara, E-mail: em@mm.unknown

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.

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• Långström, E-mail: bl@mm.unknown

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.

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• Räsänen, E-mail: pr@mm.unknown
• Koukkula, E-mail: ak@mm.unknown
• Yli-Vakkuri, E-mail: py@mm.unknown

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.

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• Lähde, E-mail: el@mm.unknown
• Oksanen, E-mail: ao@mm.unknown

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.

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• Löyttyniemi, E-mail: kl@mm.unknown

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.

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• Leikola, E-mail: ml@mm.unknown

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.

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• Löyttyniemi, E-mail: kl@mm.unknown

The winter food of moose (Alces alces L.) was examined in 1967-68 in the Saariselkä fell area in the communes of Inari and Sodankylä, in the northern parts of the communes of Salla and Savukoski, and in the central part of the commune of Salla in eastern Lapland in Finland.

In northern parts of Salla and Savukoski 25 moose were followed during 3.-13.4.1968. This area is typical wintering terrain of moose in north-east Lapland. According to the estimate, 45% food taken by the moose was Scots pine shoots and needles, 28% birch, 17% juniper sprigs and needles, 9% willow, and 1.5% bear moss. According to observations of the researchers in 26.1.-16.5.1968, moose seemed to avoid birch, even if it was available in the area, and eat Scots pine shoots and needles and juniper.

Moose seemed to prefer willow in as a winter feed in the southern part of the area studied, where it accounts according to the present and earlier studies 50-90% of the winter food. In the northern wintering areas of moose, where willow is not as common, willow seemed to account for less than 10% of the winter food. There Scots pine is the most important winter food for moose.

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• Pulliainen, E-mail: ep@mm.unknown
• Loisa, E-mail: kl@mm.unknown
• Pohjalainen, E-mail: tp@mm.unknown

The present paper presents studies on the influence of some relatively common defects of Scots pine logs in Northern Finland on both the sawing yield and on the quality of the sawn goods. The study was based on test sawing of 25 logs for each of the defects (upright limb, heart shake and various kinds of wounds and scars) at Karihaara sawmill. The yield was graded into grades used for export timber according to the system of the sawmill. The proportion of the different export grades (U/S), fifths, sixths and culls) were used as characteristics together with the ratio of raw-wood consumption expressed as cu.ft/std.

Upright limbs occurring in a piece of sawn timber was shown to lower its quality to fifth grade in 43.5%, to sixth grade in 46.8% and to the category of culls in 6.5% of all cases. Only 3.2% of the cases the piece remained in U/S-grades. The size of the upright limb was the most important factor lowering the quality and affecting the ratio of raw-wood consumption.

Heart shakes are relatively common defects in pine logs deriving from over-mature trees. The quality-decreasing influence on the sawing yield depends clearly on the length of the shake in the cross-section. The same characteristics also decreases the ratio of raw-wood consumption. In addition, twisting and star shakes are considerably more harmful than straight ones. If rot occurs in connection with shakes, the places marred by the shakes are only capable of yielding sixth-grade sawn goods or culls.

Scar encountered in logs affect the sawn yield and its quality to quite a varying degree, but these defects themselves may also vary considerably both in size and quality. The length of the scar is highly significant as a quality-decreasing factor. If, in addition, rot is encountered, the defect is of a severe nature.

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• Heiskanen, E-mail: vh@mm.unknown

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.

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• Päivänen, E-mail: jp@mm.unknown