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Silva Fennica 1926-1997
Acta Forestalia Fennica

Articles containing the keyword 'rest'

Category : Article

article id 5638, category Article
Markku Tykkyläinen, Pentti Hyttinen, Ari Mononen. (1997). Theories of regional development and their relevance to the forest sector. Silva Fennica vol. 31 no. 4 article id 5638.
Keywords: forest policy; forest economics; regional development; restructuring; resource community; geography
Abstract | View details | Full text in PDF | Author Info

The paper elaborates upon various theories to explain economic development and restructuring in the forested regions of advanced countries. The concepts of communities based on the forest sector and the concept of restructuring are discussed before presenting the diversity of relevant theories. Different theoretical approaches in geography and regional and socio-economic sciences are analysed, and the paper concludes that each theory gives only a partial explanation of restructuring under certain conditions. This paper recommends that an explanatory framework should take into account – in addition to general explanatory factors – sectoral, local-specific and policy-related factors and the role of human agency in attempts to explain restructuring and development.

  • Tykkyläinen, E-mail: mt@mm.unknown (email)
  • Hyttinen, E-mail: ph@mm.unknown
  • Mononen, E-mail: am@mm.unknown
article id 5637, category Article
Janne Uuttera, Harri Hyppänen. (1997). Relationship between forest management planning units and spatial distribution of forest habitat components in Koli National Park. Silva Fennica vol. 31 no. 4 article id 5637.
Keywords: Finland; forest management planning; forest habitat distribution; Geographic Information Systems; kriging-interpolation; Koli National park
Abstract | View details | Full text in PDF | Author Info

This study examined the relationships between forest management planning units and patches formed by forest habitat components. The test area used was a part of Koli National Park in North Karelia, eastern Finland. Forest management planning units (i.e. forest compartments) were defined by using a traditional method of Finnish forestry which applies aerial photographs and compartment-wise field inventory. Patches of forest habitat components were divided according to subjective rules by using a chosen set of variables depicting the edaphic features and vegetation of a forest habitat. The spatial distribution of the habitat components was estimated with the kriging-interpolation based on systematically located sample plots. The comparisons of the two patch mosaics were made by using the standard tools of GIS. The results of the study show that forest compartment division does not correlate very strongly with the forest habitat pattern. On average, the mean patch size of the forest habitat components is greater and the number of these patches lower compared to forest compartment division. However, if the forest habitat component distribution had been considered, the number of the forest compartments would have at least doubled after intersection.

  • Uuttera, E-mail: ju@mm.unknown (email)
  • Hyppänen, E-mail: hh@mm.unknown
article id 5636, category Article
Timo Pukkala, Jyrki Kangas, Matleena Kniivilä, Anne-Mari Tiainen. (1997). Integrating forest-level and compartment-level indices of species diversity with numerical forest planning. Silva Fennica vol. 31 no. 4 article id 5636.
Keywords: simulation; heuristics; biodiversity conservation; forestry decision-making; environmental planning
Abstract | View details | Full text in PDF | Author Info

The study proposes a technique which enables the computation of user-defined indices for species diversity. These indices are derived from characteristics, called diversity indicators, of inventory plots, stand compartments, and the whole forest holding. The study discusses the modifications required to be made to typical forest planning systems due to this kind of biodiversity computation. A case study illustrating the use of the indices and a modified forest planning system is provided. In the case study, forest-level species diversity index was computed from the volume of dead wood, volume of broadleaved trees, area of old forest, and between-stand variety.

At the stand level, the area of old forest was replaced by stand age, and variety was described by within-stand variety. All but one of the indicators were further partitioned into two to four sub-indicators. For example, the volume of broadleaved trees was divided into volumes of birch, aspen, willow, and other tree species. The partial contribution of an indicator to the diversity index was obtained from a sub-priority function, determined separately for each indicator. The diversity index was obtained when the partial contributions were multiplied by the weights of the corresponding indicators and then were summed. The production frontiers computed for the harvested volume and diversity indices were concave, especially for the forest-level diversity index, indicating that diversity can be maintained at satisfactory level with medium harvest levels.

  • Pukkala, E-mail: tp@mm.unknown (email)
  • Kangas, E-mail: jk@mm.unknown
  • Kniivilä, E-mail: mk@mm.unknown
  • Tiainen, E-mail: at@mm.unknown
article id 5616, category Article
Hannu Hökkä, Virpi Alenius, Timo Penttilä. (1997). Individual-tree basal area growth models for Scots pine, pubescent birch and Norway spruce on drained peatlands in Finland. Silva Fennica vol. 31 no. 2 article id 5616.
Keywords: Pinus sylvestris; site quality; Picea abies; Betula pubescens; forest drainage; mixed models; peatlands; growth models
Abstract | View details | Full text in PDF | Author Info

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

  • Hökkä, E-mail: hh@mm.unknown (email)
  • Alenius, E-mail: va@mm.unknown
  • Penttilä, E-mail: tp@mm.unknown
article id 5615, category Article
Andrew P. Robinson, Timothy G. Gregoire, Harry T. Valentine. (1997). Cut-off importance sampling of bole volume. Silva Fennica vol. 31 no. 2 article id 5615.
Keywords: Monte Carlo methods; forest mensuration; mean-square error; two-stage sampling
Abstract | View details | Full text in PDF | Author Info

Cut-off importance sampling (CIS) is introduced as a means of sampling individual trees for the purpose of estimating bole volume. The novel feature of this variant of importance sampling is the establishment on the bole of a cut-off height, HC, above which sampling is precluded. An estimator of bole volume between predetermined heights HL and HU > HC is proposed, and its design-based bias and mean square error are derived. In an application of CIS as the second stage of a two-stage sample to estimate aggregate bole volume, the gain in precision realized from CIS more than offset its bias when compared to the precision of importance sampling when HC = HU.

  • Robinson, E-mail: ar@mm.unknown (email)
  • Gregoire, E-mail: tg@mm.unknown
  • Valentine, E-mail: hv@mm.unknown
article id 5614, category Article
Mika Jääskelä, Kari Heliövaara, Mikko Peltonen, Hannu Saarenmaa. (1997). Comparison of protection methods of pine stacks against Tomicus piniperda. Silva Fennica vol. 31 no. 2 article id 5614.
Keywords: forest protection; GIS; Tomicus piniperda; timber storage; insect pests; road side landings of timber; pulpwood stacks; protection of timber
Abstract | View details | Full text in PDF | Author Info

Three most promising protection methods of pine pulp wood stacks against the attacks of Tomicus piniperda L. were compared. The methods were the covering of stacks by fibreglass-strengthened paper or twofold achrylene netting, removing the upper parts of stacks, and enhanced planning of the placement of the timber store using ARC/INFO GIS-software. T. piniperda was observed to strongly prefer the upper parts of the stacks: 90 % of the beetles occurred within 0.5 meters of the top of the stacks. Covering of the stacks decreased the attack density of T. piniperda, and the protection effect of covering was 80 %. Due to long transport distances and fragmentation of forest landscape the relocation of timber store was found to be an unsuitable method in the practical level. Also, taking into account the costs of the method, removing of the upper parts of stacks was considered to be the optimal solution.

  • Jääskelä, E-mail: mj@mm.unknown (email)
  • Heliövaara, E-mail: kh@mm.unknown
  • Peltonen, E-mail: mp@mm.unknown
  • Saarenmaa, E-mail: hs@mm.unknown
article id 5613, category Article
Mikko Peltonen, Kari Heliövaara, Rauno Väisänen. (1997). Forest insects and environmental variation in stand edges. Silva Fennica vol. 31 no. 2 article id 5613.
Keywords: forest management; bark beetles; biodiversity; distribution; edge effect; forest ecology; occurrence
Abstract | View details | Full text in PDF | Author Info

Distribution and occurrence of bark beetles and other forest insects in relation to environmental variation were analysed by multivariate methods. Eight different forest edges were studied using 10 x 10 m sample plots that formed 200 m linear transects perpendicular to the forest edge. Forest edge affected the distribution of insect species only in the edges between mature, non-managed spruce stands and clear cuts or young seedling stands, but not in the pine stands. The occurrence of the selected forest insects mainly depended on variables associated with the amount and quality of suitable woody material. The most significant environmental variables were forest site type, crown canopy coverage, tree species, number of stumps, number of dead spruce trunks and amount of logging waste at site. Quantitative classification of species and sample plots showed that some specialized species (Xylechinus pilosus, Cryphalus saltuarius, Polygraphus poligraphus and P. subopacus) adapted to mature spruce forests, tended to withdraw from the forest edge to interior stand sites. By contrast many generalized species (Pityogenes chalcographus, P. quadridens, Pissodes spp., Hylurgops palliatus, Tomicus piniperda, Dryocoetes spp. and Trypodendron lineatum) benefitted from cuttings and spread over stand borders into mature forest.

  • Peltonen, E-mail: mp@mm.unknown (email)
  • Heliövaara, E-mail: kh@mm.unknown
  • Väisänen, E-mail: rv@mm.unknown
article id 5612, category Article
Gregory S. Amacher. (1997). The design of forest taxation: A synthesis with new directions. Silva Fennica vol. 31 no. 1 article id 5612.
Keywords: forest policy; North America; forest taxation; literature review; future research; Scandinavia
Abstract | View details | Full text in PDF | Author Info

In this paper, different approaches and results concerning forest tax design are reviewed. In particular, comparisons are made between Scandinavian approaches, which rely on the two-period model, and North American approaches, which largely rely on the Faustmann model. Existing work is critically evaluated according to several stylized facts that are common among forest taxation problems. These include the second-best forest policy environment, joint production of public and private forest goods, the dynamic nature of forest capital, public and private ownership, competition between forest and non-forest sectors, and global policy constraints on taxation design. The gaps in addressing stylized facts are used to motivate new research directions. Problems and appropriate public finance literature are identified for investigating forest tax policy under government budget constraints, fiscal federalism, dynamic forest tax design, open economy forest tax policy, and econometric studies of reform. One conclusion reached from discussing future research is that two period and dynamic models will continue to prove useful in analysing taxation design from the government's perspective.

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

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

  • Lilja, E-mail: al@mm.unknown (email)
  • Kurkela, E-mail: tk@mm.unknown
  • Lilja, E-mail: sl@mm.unknown
  • Rikala., E-mail: rr@mm.unknown
article id 5610, category Article
Timo Tokola, Juho Heikkilä. (1997). Improving satellite image based forest inventory by using a priori site quality information. Silva Fennica vol. 31 no. 1 article id 5610.
Keywords: forest inventory; stand characteristics; remote sensing; forest surveys; site factors; ancillary data; Landsat TM
Abstract | View details | Full text in PDF | Author Info

The purpose of this study was to test the benefits of a forest site quality map, when applying satellite image-based forest inventory. By combining field sample plot data from national forest inventories with satellite imagery and forest site quality data, it is possible to estimate forest stand characteristics with higher accuracy for smaller areas. The reliability of the estimates was evaluated using the data from a stand-wise survey for area sizes ranging from 0.06 ha to 300 ha. When the mean volume was estimated, a relative error of 14 per cent was obtained for areas of 50 ha; for areas of 30 ha the corresponding figure was below 20 per cent. The relative gain in interpretation accuracy, when including the forest site quality information, ranged between 1 and 6 per cent. The advantage increased according to the size of the target area. The forest site quality map had the effect of decreasing the relative error in Norway spruce (Picea abies) volume estimations, but it did not contribute to Scots pine (Pinus sylvestris) volume estimation procedure.

  • Tokola, E-mail: tt@mm.unknown (email)
  • Heikkilä, E-mail: jh@mm.unknown
article id 5607, category Article
Paola Virgilietti, Joseph Buongiorno. (1997). Modeling forest growth with management data: A matrix approach for the Italian Alps. Silva Fennica vol. 31 no. 1 article id 5607.
Keywords: forest dynamics; succession; growth models; matrix models; Italian Alps; Italy
Abstract | View details | Full text in PDF | Author Info

This paper reports on the possibility and difficulties in building growth models from past Forest Administration records on cut and growth in the Italian Alps. As a case study, a matrix model was calibrated for uneven-aged forests in the Valsugana valley of the Trentino province. The model gave reliable predictions over 30 years, and plausible long-term forest dynamics, including steady-states that are similar to virgin forests. The results support the view that the current forests are deeply altered as to composition, relative to what would obtain from natural growth. They also support the concept of long cyclic changes in natural stands, gradually approaching a climax state. Shortcomings of the data are that they do not come from an experimental design, they are not always accurate, and they must be supplemented with other information, especially concerning mortality. Still, these cheap and available data can lead to workable models adapted to local conditions, with many management applications.

  • Virgilietti, E-mail: pv@mm.unknown (email)
  • Buongiorno, E-mail: jb@mm.unknown
article id 5606, category Article
Pekka E. Kauppi, Pekka Hänninen, Helena M Henttonen, Antti Ihalainen, Eino Lappalainen, Maximilian Posch, Michael Starr, Pekka Tamminen. (1997). Carbon reservoirs in peatlands and forests in the boreal regions of Finland. Silva Fennica vol. 31 no. 1 article id 5606.
Keywords: climate change; boreal forests; peatlands; global warming; carbon reservoirs; carbon pools; global carbon cycles; biomass carbon; ecological temperature gradient
Abstract | View details | Full text in PDF | Author Info

The carbon reservoir of ecosystems was estimated based on field measurements for forests and peatlands on an area in Finland covering 263,000 km2 and extending about 900 km across the boreal zone from south to north. More than two thirds of the reservoir was in peat, and less than ten per cent in trees. Forest ecosystems growing on mineral soils covering 144,000 km2 contained 10–11 kg C m-2 on an average, including both vegetation (3.4 kg C m-2) and soil (uppermost 75 cm; 7.2 kg C m-2). Mire ecosystems covering 65,000 km2 contained an average of 72 kg C m-2 as peat. For the landscape consisting of peatlands, closed and open forests, and inland water, excluding arable and built-up land, a reservoir of 24.6 kg C m-2 was observed. This includes the peat, forest soil and tree biomass. This is an underestimate of the true total reservoir, because there are additional unknown reservoirs in deep soil, lake sediments, woody debris, and ground vegetation. Geographic distributions of the reservoirs were described, analysed and discussed. The highest reservoir, 35–40 kg C m-2, was observed in sub-regions in central western and north western Finland. Many estimates given for the boreal carbon reservoirs have been higher than those of ours. Either the Finnish environment contains less carbon per unit area than the rest of the boreal zone, or the global boreal reservoir has earlier been overestimated. In order to reduce uncertainties of the global estimates, statistically representative measurements are needed especially on Russian and Canadian peatlands.

  • Kauppi, E-mail: pk@mm.unknown (email)
  • Hänninen, E-mail: ph@mm.unknown
  • Henttonen, E-mail: hh@mm.unknown
  • Ihalainen, E-mail: ai@mm.unknown
  • Lappalainen, E-mail: el@mm.unknown
  • Posch, E-mail: mp@mm.unknown
  • Starr, E-mail: ms@mm.unknown
  • Tamminen, E-mail: pt@mm.unknown
article id 5569, category Article
Esa-Jussi Viitala. (1996). Assessing the effectiveness of non-profit forestry organisations: An ultimate goal approach. Silva Fennica vol. 30 no. 4 article id 5569.
Keywords: forest management; forest policy; Finland; forest owners; evaluation; forestry management associations
Abstract | View details | Full text in PDF | Author Info

This paper is an assessment of what in Finland are referred to as local forest management associations (LFMAs); the local units of a non-profit, forestry-promotion institution. First, the concept of organisational effectiveness is explored and an attempt is made to define it with respect to the LFMAs. The study then seeks to identify the environmental constraints, organisational characteristics and managerial practices differentiating the most effective and least effective associations. Discriminant analysis revealed four determinants of effectiveness: agrarian prosperity in the given area, activeness in marketing services to forest owners, the board of governors' role, and goal setting practices. The results thus indicate that the comparison of managerial policies and practices among LFMAs can provide useful information for improving their effectiveness.

  • Viitala, E-mail: ev@mm.unknown (email)
article id 5567, category Article
Pekka Punttila, Yrjö Haila. (1996). Colonisation of a burned forest by ants in the southern Finnish boreal forest. Silva Fennica vol. 30 no. 4 article id 5567.
Keywords: boreal forests; forest fires; succession; competition; Formica rufa; Formica ruginodis; ant communities; clear-cut areas
Abstract | View details | Full text in PDF | Author Info

The colonisation of a burned clear-cut by ants in southern Finland was monitored using pitfall traps, artificial nest sites, and direct nest sampling from the ground and stumps. Clearcutting and fire seemed to have destroyed wood-ant colonies (Formica rufa group), and also other mature-forest species suffered from fire. Myrmica ruginodis Nylander was able to survive only in less severely burned moist sites, whereas it benefitted from the enhanced light conditions in a non-burned clear-cut. The fire resulted in an essentially ant-free terrain into which pioneering species immigrated. The mortality of nest-founding queens appeared to be high. The results supported the hypothesis that the pioneering species tend to be those that are capable of independent colony founding, followed by species founding nests through temporary nest parasitism. The succession of the burned clear-cut differed from that of the non-burned one, suggesting that habitat selection in immigration and priority effects, i.e. competition, introduce deterministic components in the successional pathways of boreal ant communities.

  • Punttila, E-mail: pp@mm.unknown (email)
  • Haila, E-mail: yh@mm.unknown
article id 5566, category Article
Reijo Penttilä, Heikki Kotiranta. (1996). Short-term effects of prescribed burning on wood-rotting fungi. Silva Fennica vol. 30 no. 4 article id 5566.
Keywords: boreal forests; forest fires; Picea abies; polypores; controlled burning; wood decay; wood-rotting fungi; corticoid fungi; fungal community structure
Abstract | View details | Full text in PDF | Author Info

The prefire fungal flora (polypores and corticoid fungi) of 284 dead trees, mainly fallen trunks of Norway spruce (Picea abies (L.) H. Karst.), was studied in 1991 in an old, spruce-dominated mesic forest in Southern Finland. Species diversity of the prefire fungal flora was very high, including a high proportion of locally rare species and four threatened polypore species in Finland.

In 1992 part of the study area (7.3 ha) was clear-cut and a 1.7 ha forest stand in the centre of study area was left standing with a tree volume of 150 m3/ha, and later on (June 1st) in the same year the whole area was burned. Burning was very efficient and all trees in the forest stand were dead one year after the fire. Also, the ground layer burned almost completely.

In 1993 the fungal flora of the 284 sample trees was studied again. Most of the trees had burned strongly and the fungal species diversity and the evenness in community structure had decreased considerably as compared with the prefire community. Species turnover was also great, especially in corticoid fungi. Greatest losses in the species numbers occurred in moderately and strongly decayed trees, in coniferous trees and in very strongly burned trees. Fungal flora of non-decayed and slightly decayed trees, deciduous trees and slightly burned trees seemed to have survived the fire quite well, and in these groups the species numbers had increased slightly as compared with the prefire community.

Fungal species suffering from fire (anthracophobe species) were mainly growing in moderately and strongly decayed trees before the fire, whereas species favoured by fire (anthracophile species) were growing in less decayed trees. No fruitbodies of threatened polypores or other "old-forest species" of polypores were found again after fire. Some very common and effective wood-rotting fungi (e.g. Fomitopsis pinicola, Fomes fomentarius, Antrodia serialis) survived the fire quite well (anthracoxene species). Species favoured by fire were mainly ruderal species which can utilize new, competition-free resources created by fire, and species that have their optima in dry and open places also outside forest-fire areas. Some rarities, e.g. Phanerochaete raduloides and Physisporinus rivulosus, were favoured by fire.

  • Penttilä, E-mail: rp@mm.unknown (email)
  • Kotiranta, E-mail: hk@mm.unknown
article id 5604, category Article
Nigel Dudley, Jean-Paul Jeanrenaud, Adam Markham. (1996). Conservation in boreal forests under conditions of climate change. Silva Fennica vol. 30 no. 2–3 article id 5604.
Keywords: climate change; boreal forests; forest policy; forest protection; nature conservation; climate warming; WWF; World Wide Fund for Nature
Abstract | View details | Full text in PDF | Author Info

Addressing the potential impact of climate change on boreal forest ecosystems will require a range of new conservation techniques. During the early 1990s, the scope of WWF's (the World Wide Fund for Nature) forest policy work has broadened from a focus on tropical moist forests to a more general consideration of all the world's forests. Climate change is only one of a series of threats currently facing boreal forests.

Planning conservation strategies that take account of global warming is not easy when there are many computer models of climate change, sometimes predicting very different ecological effects. Climate change could result in some particularly extreme problems for the boreal forest biome. A summary of the problems and opportunities in boreal forests is presented. WWF has also been drawing up strategies for conservation on a global, regional and national level. The organization has concluded that conservation strategies aimed at combatting climate change need not be in direct conflict with other conservation planning requirements. However, proposals have emerged for ways to address the impacts of climate change that would have detrimental impacts on existing conservation plans.

  • Dudley, E-mail: nd@mm.unknown (email)
  • Jeanrenaud, E-mail: jj@mm.unknown
  • Markham, E-mail: am@mm.unknown
article id 5603, category Article
Jari Parviainen. (1996). Tasks of forest biodiversity management and monitoring deriving from international agreements. Silva Fennica vol. 30 no. 2–3 article id 5603.
Keywords: forest management; biodiversity; forest protection; sustainable forestry; international agreements; criteria of sustainability; Helsinki process; Montreal process
Abstract | View details | Full text in PDF | Author Info

Four governmental efforts are underway to reach consensus on indicators of sustainable forestry. Through the Helsinki process, European countries have developed and reached a pan-European, binding consensus, The Montreal process includes non-European Temperate and boreal forest countries, the International Tropical Timber Organization (lTTO) have developed guidelines for the sustainable management of natural tropical forests, and the countries around the Amazon basis have developed a joint initiative for creating guidelines of sustainable forest management of the Amazonian tropical rain forests. It is estimated that as many as 15–20 distinct processes are under way in the private sector by non-profit organizations and for-profit companies, some domestic and other international in scope. Perhaps the most wide-ranging definition work of non-governmental organizations is the undertake by the Forest Stewardship Council, FSC. The paper discusses the Helsinki and Montreal processes and the tasks for research.

  • Parviainen, E-mail: jp@mm.unknown (email)
article id 5602, category Article
Anatoly Pisarenko, Valentin Strakhov. (1996). Development and utilization of Russian forest resources. Silva Fennica vol. 30 no. 2–3 article id 5602.
Keywords: forest management; wild berries; forest resources; forest products; natural products; Russian Federation
Abstract | View details | Full text in PDF | Author Info

A presentation based on the historical development of Russia is given in the form of an overview of the development of Russian forest resources, of the wood, non-wood, and biological aspects of the forest ecosystem. The list of non-wood forest resources includes resin, saps, oils, berries, wild nuts, mushrooms, hay harvesting, game animals, etc. The dynamics of the system are presented in the light of the data of the Forest State Account (FSA) of Russia for the period 1956–1993. The most significant changes in the dynamics of Russia's forest resources are related to concentrated, large-scale wood harvesting operations. The dynamics of non-wood resources follow the process of the economic recession in all parts of the forest sector of Russia, the said recession having begun in the mid-1980s. The forests of Russia are considered to be of immense social and cultural value and a globally significant factor contributing to the sustainable development of forest resources.

  • Pisarenko, E-mail: ap@mm.unknown (email)
  • Strakhov, E-mail: vs@mm.unknown
article id 5601, category Article
Jari Parviainen. (1996). Impact of fire on Finnish forest in the past and today. Silva Fennica vol. 30 no. 2–3 article id 5601.
Keywords: forest fires; biodiversity; Finland; prescribed burning; forest ecology; wildfires; slash and burn cultivation
Abstract | View details | Full text in PDF | Author Info

Nearly every forest land in Finland has been burnt down by a wildfire at least once during the past 400–500 years. Slash and burn cultivation (1700–1920) was practised on 50–75 percent of Finland's forests, while prescribed burning (1920–1990) has been applied to 2–3 percent of the country's forests. Because of land-use changes and efficient fire prevention and control systems, the occurrence of wildfires in Finland has decreased considerably during the past few decades. Owing to the biodiversity and ecologically favourable influence of fire, the current tendency is to revive the use of controlled fire in forestry in Finland. Prescribed burning is used in forest regeneration and endeavours are being made to revert old conservation forests to the starting point of succession through forest fires.

  • Parviainen, E-mail: jp@mm.unknown (email)
article id 5600, category Article
Anton K. Chtchoukine. (1996). North European platyphyllous forests: biodiversity dynamics and climate changes in northwest European Russia. Silva Fennica vol. 30 no. 2–3 article id 5600.
Keywords: biodiversity; reforestation; climatic change; tree species composition; broadleaved forests; deciduous forests
Abstract | View details | Full text in PDF | Author Info

Distribution, biodiversity and reforestation dynamics of the platyphyllous forests in the Northwest European Russia were investigated. Data assembled from 21 landscape regions (250–350 km2 each) show special features of small-leaved lime (Tilia cordata Mill., Norway maple (Acer platanoides L.), mountain elm (Ulmus glabra Mill.) and English oak (Qurecus robur L.) reforestation during the last two decades. New tendencies were found for the taiga areas with natural Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) vegetation. Natural platyphyllous reforestation in cut spruce areas poses as supposed a special question for forest management policy in the relationship to global climate changes. Feasible unsustainability of the common types of succession (Norway spruce - European birch (Betula pendula Roth); Norway spruce - European aspen (Populus tremula L.)) is discussed. Biodiversity of herbs, shrubs and tree species of platyphyllous forests is high and complex and is situated in 4–15 old-growth relics in each landscape region. Low-level genotype heterogeneity of nemoral flora species of such isolated populations is presumed. Special biodiversity conservation regulations are proposed.

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

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

  • Gorshkov, E-mail: vg@mm.unknown (email)
  • Bakkal, E-mail: ib@mm.unknown
article id 5598, category Article
Timo Kuuluvainen, Kari Leinonen, Markku Nygren, Antti Penttinen. (1996). Statistical opportunities for comparing stand structural heterogeneity in managed and primeval forests: an example from boreal spruce forest in southern Finland. Silva Fennica vol. 30 no. 2–3 article id 5598.
Keywords: boreal forests; Norway spruce; biodiversity; Picea abies; stand structure; semivariance; spatial analysis; K-function; structural variation
Abstract | View details | Full text in PDF | Author Info

The horizontal and vertical stand structure of living trees was examined in a managed and in a primeval Norway spruce-dominated forest in Southern Finland. Tree size distributions (DBHs, tree height) were compared using frequency histograms. The vertical distribution of tree heights was illustrated as tree height plots and quantified as the tree height diversity (THD) using the Shannon-Weaver formula. The horizontal spatial pattern of trees was described with stem maps and quantified with Ripley's K-function. The spatial autocorrelation of tree sizes was examined with semivariogram analysis. In the managed forest the DBH and height distributions of trees were bimodal, indicating a two-layered vertical structure with a single dominant tree layer and abundant regeneration in the understory. The primeval forest had a much higher total number of trees which were rather evenly distributed in different diameter and tree height classes. The K-function summaries for trees taller than 15 m indicated that the primeval stand was close to complete random pattern. The managed stand was regular at small distances (up to 4 m). The semivariograms of tree sizes (DBH tree height) showed that the managed forest had a clear spatial dependence in tree sizes up to inter-tree distances of about 12 meters. In contrast, the primeval spruce forest had a variance peak at very short inter-tree distances (< 1 m) and only weak spatial autocorrelation at short inter-tree distances (1–5 m). Excluding the understory trees (h < 15 m) from the analysis drastically changed the spatial structure of the forest as revealed by semivariograms. ln general, the structure of the primeval forest was both horizontally and vertically more variable and heterogeneous compared to the managed forest. The applicability of the used methods in describing fine-scale forest structure i discussed.

  • Kuuluvainen, E-mail: tk@mm.unknown (email)
  • Leinonen, E-mail: kl@mm.unknown
  • Nygren, E-mail: mn@mm.unknown
  • Penttinen, E-mail: ap@mm.unknown
article id 5595, category Article
R.A. Fleming. (1996). A mechanistic perspective of possible influences of climate change on defoliating insects in North America's boreal forests. Silva Fennica vol. 30 no. 2–3 article id 5595.
Keywords: climate change; disturbance regimes; boreal forest dynamics; Abies balsamea; natural selection; North America; Choristoneura fumiferana; insect outbreaks; phenological relationships; plant quality; extreme weather; thresholds
Abstract | View details | Full text in PDF | Author Info

There is no doubt that tree survival, growth, and reproduction in North America's boreal forests would be directly influenced by the projected changes in climate if they occur. The indirect effects of climate change may be of even greater importance, however, because of their potential for altering the intensity, frequency, and perhaps even the very nature of the disturbance regimes which drive boreal forest dynamics. Insect defoliator populations are one of the dominating disturbance factors in North America's boreal forests and during outbreaks trees are often killed over vast forest areas. If the predicted shifts in climate occur, the damage patterns caused by insects may be considerably changed, particularly those of insects whose temporal and spatial distributions are singularly dependent on climatic factors. The ensuing uncertainties directly affect depletion forecasts, pest hazard rating procedures, and long-term planning for pest control requirements. Because the potential for wildfire often increases in stands after insect attack, uncertainties in future insect damage patterns also lead to uncertainties in fire regimes. In addition, because the rates of processes key to biogeochemical and nutrient recycling are influenced by insect damage, potential changes in damage patterns can indirectly affect ecosystem resilience and the sustainability of the multiple uses of the forest resource.

In this paper, a mechanistic perspective is developed based on available information describing how defoliating forest insects might respond to climate warming. Because of its prevalence and long history of study, the spruce budworm, Choristoneura fumiferana Clem. (Lepidoptera: Tortricidae), is used for illustrative purposes in developing this perspective. The scenarios that follow outline the potential importance of threshold behaviour, historical conditions, phenological relationships, infrequent but extreme weather, complex feedbacks, and natural selection. The urgency of such considerations is emphasized by reference to research suggesting that climate warming may already be influencing some insect lifecycles.

  • Fleming, E-mail: rf@mm.unknown (email)
article id 5594, category Article
Anssi Niskanen, Tapio Rantala, Olli Saastamoinen. (1996). Economic impacts of carbon sequestration in reforestation: examples from boreal and moist tropical conditions. Silva Fennica vol. 30 no. 2–3 article id 5594.
Keywords: boreal forests; carbon; forestry; Finland; Philippines; profitability; tropical forests; forest plantations
Abstract | View details | Full text in PDF | Author Info

The impact of carbon sequestration on the financial profitability of four tree plantation cases in Finland and the Philippines were examined. On the basis of stem wood growth; the accumulation of carbon in forest biomass, the formation and decomposition of litter, and the carbon flow in wood-based products were assessed for each reforestation case representing boreal (Finland) and moist tropical conditions (the Philippines). Using different unit values for carbon sequestration the profitability of reforestation was estimated for a fixed 100-year period on a per hectare basis. The financial profitability of reforestation increased notably when the sequestered carbon had high positive values. For example, when the value of carbon sequestration was set to be Twenty-five United States Dollar per megagram of carbon (25 USO/Mg C), the internal rate of return (IRR) of a reforestation investment with Norway spruce (Picea abies (L.) H. Karst.) in Finland increased from 3.2% to 4.1 %. Equally, the IRR of reforestation with mahogany (Swietenia macrophylla King) in the Philippines increased from 12.8% to 15.5%. The present value of carbon sequestration ranged from 39–48% and from 77–101% of the present value of the reforestation cost in Finland and the Philippines, respectively when a 25 USO/Mg C shadow price and a 5% discount rate were applied. Sequestration of one mg of carbon in reforestation in Finland and the Philippines was estimated to cost from 10.5–20.0 and from 4.0–13.6 USO, respectively.

  • Niskanen, E-mail: an@mm.unknown (email)
  • Rantala, E-mail: tr@mm.unknown
  • Saastamoinen, E-mail: os@mm.unknown
article id 5593, category Article
Malle Mandre, Jaan Klõseiko, Vaike Reisner, Hardi Tullus. (1996). Assessment of CO2 fluxes and effects of possible climate changes on forests in Estonia. Silva Fennica vol. 30 no. 2–3 article id 5593.
Keywords: climate change; CO2; forestry; Estonia; carbon dioxide; forest composition; Forest Gap model
Abstract | View details | Full text in PDF | Author Info

The present study is the first attempt to carry out an inventory of greenhouse gas (GHG) fluxes in the forests of Estonia. The emission and uptake of CO2 as a result of forest management, forest conversion and abandonment of cultivated lands in Estonia was estimated. The removal of GHG by Estonian forests in 1990 exceeded the release about 3.3 times. Changes in the species composition and productivity of forest sites under various simulated climate change scenarios have been predicted by using the Forest Gap Model for the central and coastal areas of Estonia. The computational examples showed that the changes in forest community would be essential.

  • Mandre, E-mail: mm@mm.unknown (email)
  • Klõseiko, E-mail: jk@mm.unknown
  • Reisner, E-mail: vr@mm.unknown
  • Tullus, E-mail: ht@mm.unknown
article id 5590, category Article
Heikki Hänninen, Seppo Kellomäki, Ilkka Leinonen, Tapani Repo. (1996). Overwintering and productivity of Scots pine in a changing climate. Silva Fennica vol. 30 no. 2–3 article id 5590.
Keywords: Pinus sylvestris; climate change; ecosystems; frost damage; phenology; forest ecology; gap-type model; model accuracy; model realism; overvintering
Abstract | View details | Full text in PDF | Author Info

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

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

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

  • Gorshkov, E-mail: vg@mm.unknown (email)
  • Bakkal, E-mail: ib@mm.unknown
  • Stavrova, E-mail: ns@mm.unknown
article id 5587, category Article
Dina I. Nazimova, N.P. Polikarpov. (1996). Forest zones of Siberia as determined by climatic zones and their possible transformation trends under global change. Silva Fennica vol. 30 no. 2–3 article id 5587.
Keywords: climate change; boreal forests; modelling; Siberia; climatic zones; Russian Federation; zonal forest types; climatic ordination
Abstract | View details | Full text in PDF | Author Info

A system of zonality in Siberia has been formed under the control of continentality, which provides the heat and humidity regimes of the forest provinces. Three sectors of continentality and four to six boreal sub-zone form a framework for the systematization of the different features of land cover in Siberia. Their climatic ordination provides the fundamental basis for the principal potential forest types (composition, productivity) forecasting the current climate. These are useful in predicting the future transformations and succession under global change.

  • Nazimova, E-mail: dn@mm.unknown (email)
  • Polikarpov, E-mail: np@mm.unknown
article id 5575, category Article
Gintautas Mozgeris. (1996). Dynamic stratification for estimating pointwise forest characteristics. Silva Fennica vol. 30 no. 1 article id 5575.
Keywords: stand characteristics; forest mensuration; SMI forest management planning system; dynamic stratification; static stratification
Abstract | View details | Full text in PDF | Author Info

This paper deals with the testing of dynamic stratification for estimating stand level forest characteristics (basal areas, mean diameter, mean height and mean age) for a 117 ha study areas in Finland. The results do not show possibilities to achieve more accurate estimates using only Landsat TM principal components as auxiliary data opposed to static stratification. It was found that in dynamic stratification non-measured observations should be assigned the mean characteristics of the measured observations that belong to the same cube (class) instead of stratification variable classes until a certain limit. If only one principal component is used the number of classes has, however, little influence. Low field values are overestimated and high values underestimated.

The only successful results were obtained using two variables of different origin – the qualitative development stage class and the quantitative 1st principal component. The lowest root mean square error in estimating basal area was 6.40 m2/ha, mean diameter 3.34 cm, mean height 2.65 m and mean age 14.06 years. This increase of stratification accuracy is mainly resulted by the use of development stage class as an auxiliary variable.

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

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

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

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

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

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

  • Vanha-Majamaa, E-mail: iv@mm.unknown (email)
  • Suominen, E-mail: rs@mm.unknown
  • Tonteri, E-mail: tt@mm.unknown
  • Tuittila, E-mail: et@mm.unknown
article id 5572, category Article
Markku Lehtelä, Juha-Pekka Hotanen, Pentti Sepponen. (1996). Understorey vegetation in fresh and herb-rich upland forests in southwest Lapland. Silva Fennica vol. 30 no. 1 article id 5572.
Keywords: Finland; forest soil; forest type; site classification; multivariate methods; forest vegetation
Abstract | View details | Full text in PDF | Author Info

Fresh and herb-rich upland forest sites in the north-western part of the central boreal vegetation zone in Finland were studied with respect to vegetation structure and vegetation-environment relationships (soil, stand characteristics). Two fresh heath vegetation data sets, one from the northern boreal zone and the other from the central boreal zone, were compared with the data of this study using multivariate methods.

The variation in heath forest vegetation within the climatically uniform area was mainly determined by the fertility of the soil (primarily Ca and Mg) and the stage of stand development. N, P and K content of the humus layer varied little between the vegetation classes. Fertile site types occurred, in general, on coarse-textured soils than infertile site types, may be due to the fact that the sample plots were located in various bedrock and glacial till areas, i.e. to sampling effects.

The place of the vegetational units of the study area in the Finnish forest site type system is discussed. The vegetation of the area has features in common with the northern boreal zone as well as the southern part of the central boreal vegetation zone. The results lend some support to the occurrence of a northern Myrtillus type or at least that intermediate form of fresh and herb-rich mineral soil sites commonly occur in the studied area. It is argued that the older name Dryopteris-Myrtillus type is more suitable than Geranium-Oxalis-Myrtillus type for herb-rich heath sites in the study area.

  • Lehtelä, E-mail: ml@mm.unknown (email)
  • Hotanen, E-mail: jh@mm.unknown
  • Sepponen, E-mail: ps@mm.unknown
article id 5564, category Article
Jerry Johansson. (1995). Backhoe loaders as base machines in logging operations. Silva Fennica vol. 29 no. 4 article id 5564.
Keywords: harvesting; logging; time studies; forest machines; attachments; backhoe loaders; base machines
Abstract | View details | Full text in PDF | Author Info

Time studies and an ergonomic assessment were carried out in logging operations for three logging machines based on backhoe loader chassis. The time studies were completed with a follow-up study of one backhoe loader-based single-grip harvester. The studies indicated a productivity at the same level as that of specialized Nordic logging machines. Ergonomics also proved to be good. Mean ground pressure exerted by the backhoe loader-based logging machines was little higher than for some of the conventional Nordic single-grip harvesters to which it was compared. The ability of the machines to operate in the terrain was also good, even in rough terrain.

These machines can also be used for other jobs, such as ditch digging, road building and road maintenance. The machines then function more as carriers for attachments rather than custom-built backhoe loaders. By more careful planning of operations, the machines can be used to a higher degree and more effectively. The relatively low investment cost compared to many custom-built Nordic logging machines also contributes to a reduction of operating costs.

  • Johansson, E-mail: jj@mm.unknown (email)
article id 5555, category Article
Mauno Pesonen, Arto Kettunen, Petri Räsänen. (1995). Modelling non-industrial private forest landowners’ strategic decision making by using logistic regression and neural networks: Case of predicting the choice of forest taxation basis. Silva Fennica vol. 29 no. 2 article id 5555.
Keywords: logistic regression; Finland; Neural Networks; forest owners; forest taxation; non-industrial private forest landowners,; timber management strategies
Abstract | View details | Full text in PDF | Author Info

In this study, logistic regression and neural networks were used to predict non-industrial private forests (NIPF) landowners’ choice of forest taxation basis. The main frame of reference of the study was the Finnish capital taxation reform of 1993. As a consequence of the reform, landowners were required to choose whether to be taxed according to site-productivity or realized-income during the coming transition period of thirteen years.

The most important factor affecting the landowners’ choice of taxation basis was the harvest rate during the transition period, i.e. the chosen timber management strategy. Furthermore, the estimated personal marginal tax rate and the intention to cut timber during next three years affected the choice. The descriptive landowner variables did not have any marked effect on the choice of forest taxation basis.

On average, logistic regression predicted 71% of the choices correctly; the corresponding figure for neural networks was 63%. In both methods, the choice of site-productivity taxation was predicted more accurately than the choice of realized-income taxation. An increase in the number of model variable did not significantly improve the results of neural networks and logistic regression.

  • Pesonen, E-mail: mp@mm.unknown (email)
  • Kettunen, E-mail: ak@mm.unknown
  • Räsänen, E-mail: pr@mm.unknown
article id 5554, category Article
Simo Poso, Mark-Leo Waite. (1995). Calculation and comparison of different permanent sample plot types . Silva Fennica vol. 29 no. 2 article id 5554.
Keywords: forest inventories; forest monitoring; sampling; optimum sampling unit; permanent plot analysis
Abstract | View details | Full text in PDF | Author Info

A calculation procedure is presented for calculating and analysing remeasured permanent sample plots. Data for eight different fixed and variable size plot types were simulated on the basis of two stands whose trees were mapped and measured in 1982 and 1986. The accuracy and efficiency of the plot types were assessed and compared.

The calculation procedure is based on tree-wise expansion factors and the division of tree sampled into state/measurement classes. Nine classes were required for variable size plots and six for fixed size plots. A relascope plot with basal-area factor 1 (m2/ha) proved to be most efficient for estimating basal-area at a given time and a fixed size circular plot with radius 10 m for estimating basal-area increment over a given time period.

The main problems were related to the estimation of non-measurable variables, e.g., the initial diameters of ingrowth trees, i.e., trees having passed the threshold size during the measurement period. Most problematic were cut trees belonging to the ingrowth or sample enlargement classes. It is nevertheless thought that the system is appropriate for monitoring forest changes and making sensitivity analyses with permanent sample plots.

  • Poso, E-mail: sp@mm.unknown (email)
  • Waite, E-mail: mw@mm.unknown
article id 5553, category Article
Annika Kangas, Kari T. Korhonen. (1995). Generalizing sample tree information with semiparametric and parametric models. Silva Fennica vol. 29 no. 2 article id 5553.
Keywords: forest inventories; mixed models; volume; nonparametric models; semiparametric models
Abstract | View details | Full text in PDF | Author Info

Semiparametric models, ordinary regression models and mixed models were compared for modelling stem volume in National Forest Inventory data. MSE was lowest for the mixed model. Examination of spatial distribution of residuals showed that spatial correlation of residuals is lower for semiparametric and mixed models than for parametric models with fixed regressors. Mixed models and semiparametric models can both be used for describing the effect of geographic location on stem form.

  • Kangas, E-mail: ak@mm.unknown (email)
  • Korhonen, E-mail: kk@mm.unknown
article id 5551, category Article
Jyrki Hytönen, Pekka Rossi, Anna Saarsalmi. (1995). Biomass production and nutrient uptake of short-rotation plantations. Silva Fennica vol. 29 no. 2 article id 5551.
Keywords: Betula pendula; biomass production; Betula pubescens; Alnus incana; short-rotation forestry; Salix phylicifolia; Salix x dasyclados; Salix 'Aquatica'; nutrient uptake; Salix triandra
Abstract | View details | Full text in PDF | Author Info

The biomass production and nutrient uptake of silver birch (Betula pendula Roth), downy birch (Betula pubescens Erhr.), grey alder (Alnus incana (L.) Moench), native willows Salix triandra L. and S. phylicifolia L. and exotic willows S. x dasyclados and S. ’Aquatica’ growing on a clay mineral soil field (Sukeva) and on two cut-away peatland areas (Piipsanneva, Valkeasuo) were investigated.

Biomass production of downy birch was greater than that of silver birch, and the biomass production of the native willows greater than that of the exotic ones. The performance of S. phylicifolia was the best of the studied willow species. Exotic willows were susceptible to frost damage and their winter hardiness was poor. The production of all species was lower on the clay mineral soil field than on the cut-away peatland areas. Fertilization of birches and alder – on the double dose given to the willows – increased biomass production. After 6 growing seasons the leafless biomass production of fertilized silver birch at Piipsanneca was 21 t ha-1 (at Valkeasuo 34 t ha-1) and of grey alder 24 t ha-1, and that of S. triandra after five growing seasons 31 t ha-1, S. phylicifolia 38 t ha-1 and of S. x dasyclados 16 t ha-1.

6-year-old stands of silver birch bound more nutrients per unit biomass than downy birch stands. Grey alder bound more N, Ca and Co but less Mn and Zn per unit biomass than silver and downy birch. On the field more P was bound in grey alder per unit biomass compared to downy birch. The willows had more K per unit biomass than the other tree species, and the exotic willow species more N than the native ones. Less N, K and Mg were bound per unit biomass of S. phylicifolia compared to the other tree species.

  • Hytönen, E-mail: jh@mm.unknown (email)
  • Rossi, E-mail: pr@mm.unknown
  • Saarsalmi, E-mail: as@mm.unknown
article id 5550, category Article
Jyrki Hytönen. (1995). Effect of repeated fertilizer application on the nutrient status and biomass production of Salix ’Aquatica’ plantations on cut-away peatland areas. Silva Fennica vol. 29 no. 2 article id 5550.
Keywords: biomass production; fertilization; fuelwood; peatlands; short-rotation forestry; Salix 'Aquatica'
Abstract | View details | Full text in PDF | Author Info

The effects of repeated fertilizer treatment on biomass production and nutrient status of willow (Salix ’Aquatica’) plantations established on two cut-away peatland areas in western Finland were studied over a rotation period of three years. Comparisons were made between single fertilizer applications and repeated annual fertilization.

The annually repeated fertilizer application increased the amounts of acid ammonium acetate extractable phosphorus and potassium in the soil as well as the concentrations of foliar nitrogen, phosphorus and potassium compared to single application. Depending on the fertilizer treatment and application rate, annual fertilizer application resulted in over two times higher biomass production when compared to single fertilizer application over a three-year rotation period. The effect of phosphorus fertilizer application lasted longer than that of nitrogen. The optimum fertilization regime for biomass production requires that nitrogen fertilizer should be applied annually, but the effect of phosphorus can last at least over a rotation of three years. Potassium fertilizer treatment did not increase the yield in any of the experiments during the first three years. The leafless, above-ground yield of three-year-old, annually NP-fertilized willow plantations was 9.5 t ha-1 and the total biomass, including stems, leaves, roots and the stump, averaged 17 t ha-1.

  • Hytönen, E-mail: jh@mm.unknown (email)
article id 5544, category Article
Jyrki Hytönen. (1995). Effect of fertilizer treatment on the biomass production and nutrient uptake of short-rotation willow on cut-away peatlands. Silva Fennica vol. 29 no. 1 article id 5544.
Keywords: biomass production; fertilization; fuelwood; nutrients; peatlands; short-rotation forestry; Salix; consumption
Abstract | View details | Full text in PDF | Author Info

The effects of fertilized treatment on the soil nutrient concentrations, biomass production and nutrient consumption of Salix x dasyclados and Salix ’Aquatica’ were studied in five experiments on three cut-away peatland sites in western and eastern Finland during three years. Factorial experiments with all combinations of N (100 kg ha-1 a-1), P (30 kg ha-1 a-1) and K (80 kg ha-1 a-1) were conducted.

The application of P and K fertilizers increased the concentrations of corresponding extractable nutrients in the soil as well as in willow foliage. N-fertilization increased foliar nitrogen concentration. An increase in age usually led to decreases in bark and wood N, P and K concentrations and increases in bark Ca concentrations. N-fertilization increased the three-year biomass yield 1.5–2.7 times when compared to control plots. P-fertilization increased the yield only in those experimental fields whose substrates had the lowest phosphorus concentration. K-fertilization did not increase the yield in any of the experimental fields. The highest total biomass yield of NPK-fertilized willow after three growing seasons, 23 t ha-1, was distributed in the following way: wood 42%, bark 19%, foliage 17%, stumps 6% and roots 16%. As the yield and stand age increased, more biomass was allocated in above-ground wood. Three-year-old stands (above-ground biomass 18 t ha-1) contained as much as 196 kg N ha-1, 26 kg P ha-1, 101 kg K ha-1, 74 kg Ca ha-1 and 37 kg Mg ha -1. By far the highest proportion of nutrients accumulated in the foliage. The bark and wood contained relatively high proportions of calcium and phosphorus. With an increase in age and size, the amount of nitrogen and potassium bound in one dry-mass ton of willow biomass decreased while that of phosphorus remained unchanged.

  • Hytönen, E-mail: jh@mm.unknown (email)
article id 5541, category Article
Anneli Viherä-Aarnio. (1994). Performance of micropropagated plants of silver birch (Betula pendula) in a field trial. Silva Fennica vol. 28 no. 4 article id 5541.
Keywords: Betula pendula; forestry; growth; mortality; seedlings; clones; tissue culture; clonal propagation
Abstract | View details | Full text in PDF | Author Info

Micropropagated and seed-borne plants of sliver birch (Betula pendula Roth) were compared for survival and growth in a field trial at the age of six years. Three clones for micropropagation were selected from open-pollinated progenies of selected southern Finnish plus trees at the age of 17 and 20. The three seed-borne lots were of southern Finnish stand origin. The best two lots of the experiment as regards the height and diameter growth at the age of six were the clones. The best of these differed significantly from the best-growing seed-grown lot. The weakest lot of the experiment was also a clone which was clearly slow-growing with a dense and bushy crown. Survival of the material was high (mean = 94%), and there was no damage caused by voles and elks, for example. The results clearly show that the selection of material for clonal propagation should be done carefully. The clones should also be tested for performance in the field before propagation on a large scale.

  • Viherä-Aarnio, E-mail: av@mm.unknown (email)
article id 5532, category Article
Anu Honkanen. (1994). Selection of Salix myrsinifolia clones for biomass forestry in Finland. Silva Fennica vol. 28 no. 3 article id 5532.
Keywords: biomass; selection; diameter distribution; short rotation forestry; fuelwood; production; clones; Salix phylicifolia; Salix myrsinifolia
Abstract | View details | Full text in PDF | Author Info

For biomass forestry in the inland parts of Southern and Central Finland, the obvious choice of willow species is Salix myrsinifolia. However, selection of clones of indigenous species has not yet been completed and more research and selection is needed. In the Piipsanneva old peatland trial, indigenous species of willow, mostly clones of S. myrsinifolia and S. phylicifolia, were compared in terms of biomass production, coppicing, height growth and diameter distributions. In this trial, the mean annual biomass production was not particularly high; more important results were attained in the ranking of clones. The trial strengthens the hypothesis that, over the long-term, the biomass production of S. myrsinifolia is higher than that of S. phylicifolia. It was supposed that behind the highest yield there was a clone with uniform quality, one whose diameter distribution would be narrow and positively skewed. Comparisons of parameters of Weibull functions showed that the distributions of the best clones were wide, indicating that those clones use the whole growth space better than those with narrow distribution.

  • Honkanen, E-mail: ah@mm.unknown (email)
article id 5531, category Article
Anneli Viherä-Aarnio, Anna Saarsalmi. (1994). Growth and nutrition of willow clones. Silva Fennica vol. 28 no. 3 article id 5531.
Keywords: biomass; short rotation forestry; fuelwood; nutrients; clones; hybridization; Salix
Abstract | View details | Full text in PDF | Author Info

Growth and nutrition of 20 clones representing different species and interspecific hybrids of willows (Salix spp.) growing on an abandoned field were studied. There were highly significant differences between the clones as regards the survival, number of sprouts per stool, sprout mean height and diameter and stem biomass production per stool. The differences between the clones in the concentration of all nutrients in both the leaves and stems were highly significant. 

  • Viherä-Aarnio, E-mail: av@mm.unknown (email)
  • Saarsalmi, E-mail: as@mm.unknown
article id 5401, category Article
Akmal S. Hyder, Lars Lönnstedt, Markku Penttinen. (1994). Outline of accounting for non-industrial private woodlots. Silva Fennica vol. 28 no. 2 article id 5401.
Keywords: non-industrial private forestry; financial accounting; net profit of the enterprise; calculated profit of the property; cost accounting; forest management strategies
Abstract | View details | Full text in PDF | Author Info

For non-industrial private forest (NIPF) owners land with its timber production is an example of a capital asset. Developments in the asset’s value and yield depend not only on forest management but also on other factors that the owner cannot control, for example timber prices and the production circumstances, such as soil and climate. One important basis for decision making related to management strategy and, in the short run, to cutting and silvicultural activities is economic analysis and accounting. The owner has to decide whether to invest more in his property (planting, cleaning, building of forest roads) or disinvest (sell timber or the holding). He has to find ways to increase revenue and cut costs.

However, generally accepted accounting practices for NIPF owners are lacking. Applying business economic accounting principles and forestry accounting traditions, we outline a proposal for a profit and loss accounting and balance sheet for NIPF holdings with a view towards increasing economic awareness among private owners. Key concepts are net profit of the enterprise and calculated profit of the property. Other profit measurements that are used are gross margin, forestry margin, operating margin and operating profit. Calculated profit is based on adjusted net profit. The main concern, however, is to consider the change in the holding’s market value caused by changes in stock volume, quality and price. The contents of the accounting framework development here are applied to three management strategies. The return on investment (ROI) of forestry is compared with other investment alternatives.

  • Hyder, E-mail: ah@mm.unknown (email)
  • Lönnstedt, E-mail: ll@mm.unknown
  • Penttinen, E-mail: mp@mm.unknown
article id 5399, category Article
Raisa Mäkipää. (1994). Effects of nitrogen fertilization on the humus layer and ground vegetation under closed canopy in boreal coniferous stands. Silva Fennica vol. 28 no. 2 article id 5399.
Keywords: ground vegetation; forest soils; dwarf shrubs; nitrogen fertilization; mosses; nitrogen saturation; nitrogen deposition
Abstract | View details | Full text in PDF | Author Info

Forest ecosystems may accumulate large amounts of nitrogen in the biomass and in the soil organic matter. However, there is increasing concern that deposition of inorganic nitrogen compounds from the atmosphere will lead to nitrogen saturation; excess nitrogen input does not increase production. The aim of this study was to determine the long-term changes caused by nitrogen input on accumulation of nitrogen in forest soils and in ground vegetation.

The fertilization experiments used in this study were established during 1958–1962. They were situated on 36- to 63-year-old Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands of different levels of fertility. The experiments received nitrogen fertilization 5–7 times over a 30-year period, and the total input of nitrogen was 596–926 kg/ha.

Nitrogen input increased the amount of organic matter in the humus layer and the nitrogen concentration in the organic matter. Furthermore, the total amount of nutrients (N, P, K, Ca and Mg) bound by the humus layer increased due to the increase in the amount of organic matter. However, nitrogen input decreased the biomass of ground vegetation. The nitrogen concentration of the plant material on the nitrogen-fertilized plots was higher than on the control plots, but the amount of nutrients bound by ground vegetation decreased owing to the drastic decrease in the biomass of mosses. Ground vegetation does not have the potential to accumulate nitrogen, because vegetation is dominated by slow-growing mosses and dwarf shrubs which do not benefit from nitrogen input.

  • Mäkipää, E-mail: rm@mm.unknown (email)
article id 5524, category Article
Annika Kangas. (1994). Classical and model based estimators for forest inventory. Silva Fennica vol. 28 no. 1 article id 5524.
Keywords: models; forest inventories; estimation; systematic cluster sampling; covariance structure
Abstract | View details | Full text in PDF | Author Info

In this study, model-based and design-based inference methods are used for estimating mean volume and its standard error for systematic cluster sampling. Results obtained with models are compared to results obtained with classical methods. The data are from the Finnish National Forest Inventory. The variation of volume in ten forestry board districts in Southern Finland is studied. The variation is divided into two components: trend and correlated random errors. The effect of the trend and the covariance structure on the obtained mean volume and standard error estimates is discussed. The larger the coefficient of determination of the trend model, the smaller the model-based estimates of standard error, when compared to classical estimates. On the other hand, the wider the range and level of autocorrelation between the sample plots, the larger the model-based estimates of standard error.

  • Kangas, E-mail: ak@mm.unknown (email)
article id 5523, category Article
Reijo Solantie. (1993). Snow and soil frost in Finnish forests. Silva Fennica vol. 27 no. 4 article id 5523.
Keywords: snow damages; Finland; ground vegetation; forest ecology; flora; snow cover; fauna
Abstract | View details | Full text in PDF | Author Info

Abundant snowfalls and thick snow cover influence forest ecology mainly in two ways. Snow loading increases the number of damaged stems, which increases the amount of decay in stems, in its turn important for many animals. Second, the ground remains unfrozen under the snow cover, which is of crucial importance for many perennial species of ground vegetation. These winter phenomena also have influenced the early Finnish culture as man in his everyday life in the wilderness was in close contact with nature. In this paper, ecological interactions between snow conditions, forest flora, fauna and early culture are discussed mainly with reference to the province of Uusimaa in Southern Finland.

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

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

The PDF includes an abstract in Finnish.

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

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

The PDF includes an abstract in Finnish.

  • Korhonen, E-mail: kk@mm.unknown (email)
article id 5519, category Article
Jyrki Kangas, Jari Karsikko, Laura Laasonen, Timo Pukkala. (1993). A method for estimating the suitability function of wildlife habitat for forest planning on the basis of expertise. Silva Fennica vol. 27 no. 4 article id 5519.
Keywords: forest management; models; wildlife management; black grouse; production functions; multiple use; Lururus tetrix
Abstract | View details | Full text in PDF | Author Info

In the method presented in this study, a group of experts evaluate, in a pairwise manner, a set of forest areas with respect to the game species considered. On the basis of these comparisons, relative priorities of forest areas are estimated using the eigenvalue technique. Using regression analysis, a habitat suitability function is estimated in which the priority is predicted by measures already familiar in forest planning. As a case study, a habitat suitability function was estimated for black grouse (Tetrao tetrix, Lururus tetrix L.). The function is applicable in forestry planning carried out using modern planning techniques.

The PDF includes an abstract in Finnish.

  • Kangas, E-mail: jk@mm.unknown (email)
  • Karsikko, E-mail: jk@mm.unknown
  • Laasonen, E-mail: ll@mm.unknown
  • Pukkala, E-mail: tp@mm.unknown
article id 5517, category Article
Tuomo Kotimäki. (1993). Ristipaineet valtion metsien käytön valintatilanteissa. Silva Fennica vol. 27 no. 3 article id 5517.
English title: Contradictory targets in the use of state forests of Finland.
Original keywords: valtionmetsät; Metsähallitus; metsänhoito; metsien monikäyttö; aluepolitiikka; maankäyttö; kestävä metsätalous
English keywords: forest management; Finland; forest management planning; Forest Service; state forests; multiple use of forests; conflicting targets; land use; regional planning
Abstract | View details | Full text in PDF | Author Info

The paper discusses the principles of forest management in the state forests of Finland, and the contradictions in choosing between the different land uses. These principles of the forest management are sustainable use of natural resources, economic and effective management, and taking in account nature conservation, protection of environment, recreation services and employment issues in all activities of the Forest Service. Even regional policy affects the management planning in the state forests.

  • Kotimäki, E-mail: tk@mm.unknown (email)
article id 5516, category Article
Veli-Pekka Järveläinen. (1993). Yksityismetsätalous ja arvojen muutos. Silva Fennica vol. 27 no. 3 article id 5516.
English title: Private forestry and the changing values.
Original keywords: metsänhoito; yksityismetsätalous; metsänomistajat; arvot
English keywords: forest management; forestry; values; Finland; forest owners; private forests
Abstract | View details | Full text in PDF | Author Info

Forests have been economically important for Finnish private forest owners at all times, but the use of forests has changed markedly since 1920s, when forests were mainly used for collecting household timber, and the cuttings were often exploitative because of the farmer’s need for money. The present situation is totally different. Need for household timber is marginally small, and private forestry produces mainly timber for sale. The sales of timber have increased, but due to better forest management the growing stock in the private forests has increased. The article discusses how the changes in values of forest owners has and will affect the stage of private forestry.

  • Järveläinen, E-mail: vj@mm.unknown (email)
article id 5515, category Article
Seppo Vehkamäki. (1993). Metsien käytön muutospaineet. Silva Fennica vol. 27 no. 3 article id 5515.
English title: Pressures for changes in the use of forests.
Original keywords: metsänhoito; metsätalous; metsien monikäyttö; kestävyys; tuottavuus; tehokkuus
English keywords: forest management; productivity; sustainability; forestry; multiple use of forests; effectiveness
Abstract | View details | Full text in PDF | Author Info

The paper discusses how the general trend towards increasing growth and productivity in the European societies is expressed also in forestry. It is reflected, for instance, in the increasing production and productivity of forest industries. Technological progress and call for economic growth require great flexibility from all resources. These pressures for effectiveness and production also concern Finnish forestry and forest management. Industrialization, urbanization and development of forestry have increased the pressure to use forests in recreation, preserving human environment and nature conservation in addition to production of timber. Through the development the definition of sustainability has become wider.

  • Vehkamäki, E-mail: sv@mm.unknown (email)
article id 5514, category Article
Walter Sekot. (1993). Forest dynamics. Silva Fennica vol. 27 no. 3 article id 5514.
Keywords: forestry; simulation; forest decline; operations research; risks
Abstract | View details | Full text in PDF | Author Info

The paper deals with the application of forest dynamics. Reference is made to two studies, which have been carried out at a national level. The simulations of forest decline as well as the production of exceedingly thick timber of spruce and fir provide various examples of the major problems of forest simulation and of some possible solutions. It is pointed out that the statistical analysis of empirical data is most important for modelling and it might bring about even more valuable results than the ultimate simulation itself.

  • Sekot, E-mail: ws@mm.unknown (email)
article id 5509, category Article
Markku Siitonen. (1993). Experiences in the use of forest management planning models. Silva Fennica vol. 27 no. 2 article id 5509.
Keywords: forest policy; forest inventories; stand management; linear programming; forest resources
Abstract | View details | Full text in PDF | Author Info

Model-based information systems have proved valuable planning tools for analysing the production possibilities of forests as well as for understanding forest resources dynamics, stand management practices and forest economics. Computerized forest models implemented in the users’ information systems facilitate the transfer and application of research results in practical forestry.

Conclusions and visions concerning modelling are drawn from experiences in developing the MELA system and its application in solving timber production problems on both the national and forest holding level in Finland. The precondition for predicting forest resource dynamics and for planning the utilization of forests is to accept conditions, uncertainties and a restricted period of time.

The interactive process of forest resource, growth and drain monitoring, and forest management planning supported by forest research and modelling, are the means to enable an operational information base for a dynamic regulation and adaptation strategy for forest resource management under changing conditions and uncertainty.

The PDF includes an abstract in Finnish.

  • Siitonen, E-mail: ms@mm.unknown (email)
article id 5508, category Article
Kullervo Kuusela. (1993). Trends of European forest resources on the basis of the FAO/ECE Timber Committee resource assessments. Silva Fennica vol. 27 no. 2 article id 5508.
Keywords: growing stock; Europe; forest resources; fellings; increment
Abstract | View details | Full text in PDF | Author Info

Europe’s forest area has increased 5 million ha since the late 1960s. The growing stock has increased 43% and the net annual increment 55% in exploitable forests since 1950. A part of the reported increase is caused by sampling inventories, which have been made in greater part of the countries. Sampling inventories have corrected earlier underestimates of the growing stock and the increment.

The difference between the annual net increment and fellings has increased since 1950. The net increment, 584 million m3, exceeded fellings, 408 million m3, by 176 million m3, in exploitable forests in 1990. If fellings could be increased to equal the increment, Europe would be an exporter of forest products.

A greater increase in the density, in the age and in the mean volume of forests per hectare threaten the biological stability of the growing stock. Degrading of the stock, increasing natural losses and deteriorating environmental qualities of forests can only be prevented by increased fellings and by forest regeneration.

The PDF includes an abstract in Finnish.

  • Kuusela, E-mail: kk@mm.unknown (email)
article id 5507, category Article
John L. Innes. (1993). Methods to estimate forest health. Silva Fennica vol. 27 no. 2 article id 5507.
Keywords: damage; monitoring; crown condition; air pollution; bioindicators; forest healt; indicator organisms
Abstract | View details | Full text in PDF | Author Info

A range of different indices are available for assessing the health of trees in forests. An even larger range can be used for the assessment of the health of forest ecosystems. Most studies made in connection with ”forest decline” and the impact of air pollution and other environmental stresses on forests have concentrated on the assessment of crown transparency and crown discoloration in individual trees. These are non-specific indicators which are now known to be sometimes of relatively little value when determining the health of a forest ecosystem. Numerous problems exist with both, and the standardisation of assessments between and even within countries has not been achieved. Consequently, studies claiming to compare ”defoliation” between different countries cannot be substantiated. The emphasis on crown transparency and crown discoloration has resulted in the neglect of a number of other indices that could be of considerable value. These include a variety of visual measures of crown condition and also several non-visual bioindicators. Some of these techniques are objective, reducing the present reliance on observed standardization. A large number of potential techniques are currently at the research stage and have yet to be adequately tested in field trials. This represent an area where a substantial amount of further research is required.

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

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

The PDF includes an abstract in Finnish.

  • Heikkilä, E-mail: rh@mm.unknown (email)
  • Härkönen, E-mail: sh@mm.unknown
article id 5499, category Article
Niels Elers Koch. (1993). Outlines of environmental policy concerning forests in the European Community. Silva Fennica vol. 27 no. 1 article id 5499.
Keywords: forest policy; forestry; European Community; EC; Forestry Action Programme; environmental policy; forestry strategy; conservation of habitats
Abstract | View details | Full text in PDF | Author Info

The paper, presented at the seminar ”Forestry in Europe: Implications of European Integration for National Forestry”, discusses the effects of first Forestry Action Programme in the European Community, UNCED 1992, the European Community’s new Forestry Strategy and the second Forestry Action Programme directives of conservation of habitats on forestry within the EC.

  • Koch, E-mail: nk@mm.unknown (email)
article id 5498, category Article
Ernst Wermann. (1993). Outlooks of forestry in the European Community with special emphasis on recycling. Silva Fennica vol. 27 no. 1 article id 5498.
Keywords: forest policy; forestry; Europe; recycling; subsidies; European Community; EC; Forestry Action Program
Abstract | View details | Full text in PDF | Author Info

The paper, presented at the seminar ”Forestry in Europe: Implications of European Integration for National Forestry”, discusses the meaning of the European Community for the forestry sector, putting a special emphasis on recycling. Subsidies and the so-called ”Forestry Action Program” are among the topics that have raised controversial discussions within the EC. In addition, wood fibre recycling and the EC draft directive on packaging waste includes ambiguous targets for recycling.

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

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

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

The PDF includes an abstract in Finnish.

  • Nieppola, E-mail: jn@mm.unknown (email)
article id 5492, category Article
Ismo Nousiainen, Timo Pukkala. (1992). Use of computer graphics for predicting the amenity of forest trails. Silva Fennica vol. 26 no. 4 article id 5492.
Keywords: forest management; forest planning; simulation; landscape; recreation; amenity value of forests
Abstract | View details | Full text in PDF | Author Info

Ten trails, one kilometre each, were evaluated by 15 persons for scenic beauty, recreational value and variety. All trails passed through commercially managed forests dominated by conifers. The trails were first evaluated by viewing computer simulations based on a series of graphical illustrations of forest landscapes, then from a slide show, and finally in the field. In the computer simulation and slide show, landscape pictures along the trail at an interval of 35–40 m were presented for 3–4 seconds. The ranks between slide show and field were slightly more similar than those between simulation and field. The mean correlation of 12 persons between the field ranking and assessment of either computer simulations or slide shows or graphics than scenic beauty or recreational value. Spearman’s rank correlations computed from median scores of a group of 12 peers were clearly better than the average of individual persons varying from 0.6 to 0.9.

The PDF includes an abstract in Finnish

  • Nousiainen, E-mail: in@mm.unknown (email)
  • Pukkala, E-mail: tp@mm.unknown
article id 5491, category Article
Kari T. Korhonen. (1992). Calibration of upper diameter models in large scale forest inventory. Silva Fennica vol. 26 no. 4 article id 5491.
Keywords: models; forest inventories; simulation; diameter; estimation
Abstract | View details | Full text in PDF | Author Info

Models for estimating the upper diameter of trees were constructed using sample tree data measured in the 7th National Forest Inventory in Finland. Calibration of the models was tested with data from the 8th National Forest Inventory. The results showed that using mixed estimation for combining the two data sets improves the reliability of the models. Models and methods used in this study can be recommended for use in forest inventories.

The PDF includes an abstract in Finnish.

  • Korhonen, E-mail: kk@mm.unknown (email)
article id 5489, category Article
Markku Penttinen, Matti Kinnunen. (1992). Profitability of forestry in jointly-owned forests of Northeastern Finland and Lapland. Silva Fennica vol. 26 no. 4 article id 5489.
Keywords: forest management; forestry; northern Finland; profitability; co-ownership; jointly owned forest holdings
Abstract | View details | Full text in PDF | Author Info

The profitability of jointly owned forest holdings in the two northernmost forest board districts of Finland was studied by means of ratio analysis. A time series of profit and loss statements and balance sheets from 33 holdings covering the fiscal years ending 1981–1990 served as the database. The studied area was 348,038 ha, the allowable cut 304,300 m3 per year and the average turnover, deflated by the wholesale price index, FIM 57.6 million per year. The key result obtained was that the average annual profit was FIM 107 per hectare and FIM 110 per m3. The time series showed that the ratios had increased significantly over the calculation period.

The PDF includes an abstract in Finnish.

  • Penttinen, E-mail: mp@mm.unknown (email)
  • Kinnunen, E-mail: mk@mm.unknown
article id 5485, category Article
Pekka Ripatti. (1992). Yksityistilojen metsäalan muutokset Kaakkois-Suomessa 1986-1991. Silva Fennica vol. 26 no. 3 article id 5485.
English title: Forest area changes of non-industrial private forest holdings in southeast Finland, 1986–1991.
Original keywords: yksityismetsät; yksityismetsätalous; Kaakkois-Suomi; tilakoko
English keywords: Finland; private forestry; farm size; forest holdings
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to describe the total change of forest area in non-industrial private forest holdings in southeast Finland, 1986–1991. The average gross decrease of forest area was 1.7 hectares, whereas the average gross increase was 1.2 hectares. Consequently, the average size of holdings decreased from 32.5 to 32.0 hectares. The most important factors affecting the changes of forest area were the inheritance system, resulting in a decrease of 0.7 ha, and reclassification of forestry land, producing an increase of 0.4 ha per holding. The increase of small, under 10 ha holdings accounted for much of the structural change.

The PDF includes an abstract in English.

  • Ripatti, E-mail: pr@mm.unknown (email)
article id 5484, category Article
Jyrki Kangas, Timo Pukkala. (1992). A decision theoretic approach applied to goal programming of forest management. Silva Fennica vol. 26 no. 3 article id 5484.
Keywords: forest management; models; forest planning; decision analysis; goal programming; optimization methods
Abstract | View details | Full text in PDF | Author Info

An alternative approach to formulating a forestry goal programming problem is presented. First, single objective optima levels are solved. The Analytical Hierarchy Process is applied in the estimation of a priori weights of deviations from the goal target levels. The ratios of the weights can be interpreted as relative importance of the goals, respectively. The sum of the weighted deviations from all single optima levels associated with the management goals is minimized. Instead of absolute deviations, relative ones are used. A case study problem of forest management planning with several objectives, measured in different units, is analysed.

The PDF includes an abstract in Finnish.

  • Kangas, E-mail: jk@mm.unknown (email)
  • Pukkala, E-mail: tp@mm.unknown
article id 5480, category Article
Erkki Verkasalo. (1992). Forest industry as a producer and consumer of wood-based energy in Finland. Silva Fennica vol. 26 no. 2 article id 5480.
Keywords: Finland; fuelwood; fuels; forest products industries; wood residues; black liquor; calorific value
Abstract | View details | Full text in PDF | Author Info

This article summarises the importance of forest industry in the acquisition and consumption of wood-based energy in Finland. Opportunities to increase the efficiency of energy utilization further are discussed, as well.

The forest industry uses 25% of the total energy and 40% of the total electricity. It also generates considerable amounts of heat and electric power as by-products of wood-processing. Wood in different forms accounts for 64% of the fuels of the forest industry. Consequently, the need for outside, imported energy is minute. Black liquor of pulping is dominant as a source of wood-based energy. In addition, plenty of wood residues (bark, saw dust, planer shavings, grinder dust, screening reject of chips) and minor amounts of for wood processing unsuitable fractions obtained in conjunction with harvesting small-sized whole-trees, tree selections and logging residues are used for energy production.

The PDF includes an abstract in Finnish.

  • Verkasalo, E-mail: ev@mm.unknown (email)
article id 5479, category Article
Douglas K. Loh, Hannu Saarenmaa. (1992). Design of integrated forest resource information systems. Silva Fennica vol. 26 no. 2 article id 5479.
Keywords: forest management; databases; information systems; X Window System
Abstract | View details | Full text in PDF | Author Info

Managing forests and other natural resources requires merging of data and knowledge from many fields. Research efforts in many countries have simultaneously aimed at computer applications to help managing the large amounts of data involved and the complexities of decision making. This has invariably led to large integrated systems. An integrated system is software that consists of modules for various tasks in natural resource management, spatial analysis, simulation and optimization, diagnostic reasoning, levels, and communicating with the user.

The paper presents an overview of the need, levels and historical development of integrated systems. Newly emerged technologies, especially object-oriented programming and the X Window System with its associated environment have given new flexibility and transparency to the designs. The client-server architecture is found out as an ideal model for integrated systems. The paper describes an implementation of these ideas, the INFORMS system that supports the information needs of district level forest management planning.

The PDF includes an abstract in Finnish.

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

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

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Kolström, E-mail: mk@mm.unknown
article id 5477, category Article
Martti Saarilahti. (1992). Skidding by sulky - a literature study. Silva Fennica vol. 26 no. 2 article id 5477.
Keywords: work study; production; ergonomics; forest work; labour-intensity; sulkies
Abstract | View details | Full text in PDF | Author Info

Speed and load sizes presented in three study reports on sulky skidding were compared with estimates based on ergonomic models. Speed and load size estimates were closely correlated with the observed values, when a 400 W energy expenditure of the subject was used. This corresponds to less than half of his submaximal oxygen intake and matches well with the heart rate given in one of the time studies. It seems possible to develop methods for evaluating the work pace/production rate for sulky skidding in varying terrain conditions.

The PDF includes an abstract in Finnish.

  • Saarilahti, E-mail: ms@mm.unknown (email)
article id 5471, category Article
Hannu Fritze. (1992). Effects of environmental pollution on forest soil microflora - a review. Silva Fennica vol. 26 no. 1 article id 5471.
Keywords: soil respiration; forest soil; litter decomposition; acidification; lime; heavy metals; pollution; microflora; fungal hyphae
Abstract | View details | Full text in PDF | Author Info

The article is a literature review focusing on the reaction of soil respiration, litter decomposition and microflora of forest soils to various pollutants like acidic deposition, heavy metals and unusual high amounts of basic cations. There is a great deal of evidence indicating that environmental pollution affects soil microbial activity and community structure. Much of the data originates from experimental designs where high levels of pollutants were applied to the soil under field or laboratory conditions. Furthermore, many were short-term experiments designed to look for large effects. These experiments have an indicative value, but it has to be kept in mind that environmental pollution is a combination of many pollutants, mostly at low concentrations, acting over long periods of time. There is therefore consequently a demand for research performed in natural forest environments polluted with anthropogenic compounds. 

  • Fritze, E-mail: hf@mm.unknown (email)
article id 5468, category Article
Seppo Kellomäki, Heikki Hänninen, Taneli Kolström, Risto Lauhanen, Ulla Mattila, Brita Pajari, Hannu Väisänen. (1992). A simulation model for the succession of the boreal forest ecosystem. Silva Fennica vol. 26 no. 1 article id 5468.
Keywords: succession; gap dynamics; ecosystems; simulation models; forest ecology
Abstract | View details | Full text in PDF | Author Info

A model for the succession of the forest ecosystem is described. The growth and development of trees and ground cover are controlled by temperature and light conditions and the availability of nitrogen and water. In addition, the effects of the annual cycle of trees including the risk of frost damage, wild fire, and wind damages are contained in the model as factors which control the survival and productivity of trees. The model also makes it possible to evaluated the risk of insect attack assuming that this risk is inversely related to the growth efficiency of trees.

The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Hänninen, E-mail: hh@mm.unknown
  • Kolström, E-mail: tk@mm.unknown
  • Lauhanen, E-mail: rl@mm.unknown
  • Mattila, E-mail: um@mm.unknown
  • Pajari, E-mail: bp@mm.unknown
  • Väisänen, E-mail: hv@mm.unknown
article id 5467, category Article
E. K. Morgenstern, Y. S. Park. (1991). Breeding of Picea mariana (Mill.) B.S.P.: seed orchard and clonal approaches. Silva Fennica vol. 25 no. 4 article id 5467.
Keywords: Picea mariana; breeding; Canada; seed orchards; clonal forestry; breeding programs; backward selection
Abstract | View details | Full text in PDF | Author Info

During the past 30 years, genetics research has accumulated much information on black spruce (Picea mariana). The adoption of less intensive and faster plustree selection, establishment of seedling seed orchards and family selection significantly increased the rate of progress in improvement of the species. In New Brunswick this approach made it possible to obtain substantial quantities of seeds 10 years after the initiation of the program, and now all the seeds used in reforestation are derived from seed orchards.

Fourteen years after beginning the black spruce breeding program, second generation breeding is underway. The possibility of implementing alternative breeding strategies using ”breeding – cloning” procedures are explored for the advanced generation. Until somatic embryogenesis techniques become fully operational, ”backward selection” schemes and crossing in breeding halls followed by vegetative multiplication using serial rooted cuttings can be adopted. Larger genetic gains than those from conventional breeding are expected not only from the utilization of both additive and non-additive variances, but also from the elimination of inefficiencies of large conventional seed orchards.

  • Morgenstern, E-mail: em@mm.unknown (email)
  • Park, E-mail: yp@mm.unknown
article id 5465, category Article
Gösta Eriksson. (1991). Challenges for forest geneticists. Silva Fennica vol. 25 no. 4 article id 5465.
Keywords: tree breeding; dormancy; forest research; phenotypic plasticity; mixed populations; hardiness; change of environment
Abstract | View details | Full text in PDF | Author Info

Studies of phenotypic as well as mixed population plasticities are urgently needed in a world that supposedly experiences a gradual change of its environment. It is important to understand that man creates his environment and silviculture. This is one of the reasons why for breeding it cannot be expected to find optimal phenotypes in nature. Other reasons are the phylogenetic constraints and migration of pollen and seeds.

Forest genetics up to now is characterized by the study of one trait at a time. There is an urgent need for simultaneous analysis of several traits by the aid of genetic correlations or multivariate analysis. Generally there is a need for inclusion of larger numbers of genetic entries in forest genetic investigations.

For the long-rotation-time species there is a need to determine the curves for degree of dormancy and hardiness during the annual cycle. Information of plasticity in two-dimensional environments like water availability and temperature is needed. Studies on nutrient utilization and acquisition will tell us whether or not we must have different breeding populations for different soil fertilities. An understanding of the phase changes between juvenile and adult opens up possible applications such as faster generation turn-over in the breeding population via early flowering and early testing as well as better plants for frost-prone and weedy sites.

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

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

  • Danell, E-mail:
article id 5453, category Article
Annika Kangas. (1991). Updated measurement data as prior information in forest inventory. Silva Fennica vol. 25 no. 3 article id 5453.
Keywords: forest inventories; mixed estimator; prior information; model-based inference
Abstract | View details | Full text in PDF | Author Info

Old inventory data has widely been used as prior information in forest inventory using the method of sampling with partial replacement (SPR). In this method knowledge about forest growth has not been utilized. However, the accuracy of the inventory results can be improved if this knowledge is utilized. The usability of the inventory results can be improved if the prior information is updated by treewise growth models. In this paper a statistical basis is presented for a method in which such information can be used. The applicability of the method is also discussed. An example is given to demonstrate the method.

The PDF includes an abstract in Finnish.

  • Kangas, E-mail: ak@mm.unknown (email)
article id 5450, category Article
Bo Långström, Claes Hellqvist. (1991). Shoot damage and growth losses following three years of Tomicus-attacks in Scots pine stands close to a timber storage site. Silva Fennica vol. 25 no. 3 article id 5450.
Keywords: Picea abies; growth; forest damage; Tomicus piniperda; Tomicus minor; timber storage; insect damages; shoots
Abstract | View details | Full text in PDF | Author Info

Shoot losses due to maturation feeding by pine shoot beetles (Tomicus piniperda (L.) and T. minor (Hart.), Col., Scolytidae) and subsequent growth losses were studied in Scots pine (Pinus sylvestris L.) stands growing at different distances from a timber yard, where pine timber was stored during the years 1982–84. In autumn 1985, pine trees were felled at 20, 40, 80, 500 and 1,500 m distance from the timber yard, five trees in each distance class. Trees were analysed for beetle attack, needle biomass and growth. In autumn 1988, increment cores were taken from 20 trees in each distance class.

In 1985, different damage estimates showed that beetle damage was more than 10-fold in the crowns of pine trees growing close to the timber yard as compared to less damaged trees in greater distance. Crude needle biomass estimates indicated that the trees attacked most had lost more than half of the total foliage. Following three years of attack, basal area growth decreased for 2–3 years and recovered during the subsequent 3 years, the total period of loss thus being 5–6 years. The loss in volume growth during 1983–85 was ca. 70, 40, 20 and 10% at 20, 40, 80 and 500 m distance from the beetle source, respectively, compared to the stand at 1,500. Growth losses did not occur until the number of beetle-attacks, ”pegs”, exceeded ca. 200 per tree. The highest observed growth losses occurred in trees with more than 1,000 pegs per tree.

The PDF includes an abstract in Finnish

  • Långström, E-mail: bl@mm.unknown (email)
  • Hellqvist, E-mail: ch@mm.unknown
article id 5448, category Article
Markku Penttinen. (1991). Metsäkirjanpidon ja kustannuslaskennan toteuttaminen - 20 vuotta metsätalouden kannattavuuden kenttätutkimusta Itävallassa. Silva Fennica vol. 25 no. 2 article id 5448.
English title: Implementing forestry bookkeeping and cost accounting – 20 years of field research on the profitability of forestry in Austria.
Original keywords: metsätalous; kannattavuus; yksityismetsät; kirjanpito; metsäekonomia; kustannuslaskenta; kirjapitotilat; Itävalta
English keywords: forestry; profitability; private forests; bookkeeping; forest economics; cost accounting; private forest holdings; accounting holdings; Austria
Abstract | View details | Full text in PDF | Author Info

The profitability of forestry in the context of recent economic developments in Finland suggest a more systematic analysis of the profit and the cost structure of small-scale forestry than is normally made today. The domestic and international pressure on farming emphasizes the development of rural areas by means of other business than agriculture, in practice this may mean forestry. Financing in terms of the new law concerning agriculture requires projects to be profitable. Thus, the profitability of different lines of production, including forestry, needs to be reported more carefully than is the practice today.

A network of forestry bookkeeping farms covering the whole Austria has existed for 20 years. The organization and the operation of the forestry bookkeeping and the cost accounting system is based on the scientific cooperation and exchange of information between the organizations in charge. The practical experience and recommendations based thereon might be useful for Finland, when implementing a country-wide network of forestry bookkeeping and cost accounting.

The PDF includes an abstract in English.

  • Penttinen, E-mail: mp@mm.unknown (email)
article id 5444, category Article
Kari T. Korhonen, Matti Maltamo. (1991). The evaluation of forest inventory designs using correlation functions. Silva Fennica vol. 25 no. 2 article id 5444.
Keywords: forest inventories; correlation analysis; correlograms; sampling error; spatial correlation,
Abstract | View details | Full text in PDF | Author Info

Correlation functions of the mean volume, land use class and soil class were estimated using the data of the Finnish National Forest Inventory. Estimated functions were used for approximating the standard error of e.g. the mean volume of a cluster of plots. Standard error estimates can be used for comparing different inventory designs.

The PDF includes an abstract in Finnish.

  • Korhonen, E-mail: kk@mm.unknown (email)
  • Maltamo, E-mail: mm@mm.unknown
article id 5439, category Article
Finnish Society of Forest Science. (1991). Teemapäivä metsätieteellisen julkaisutoiminnan kehittämisestä 6.2.1991. Silva Fennica vol. 25 no. 1 article id 5439.
English title: A seminar on development of forest scientific publication, held in 6.2.1991.
Keywords: forest research; forest science; scientific publications
Abstract | View details | Full text in PDF | Author Info

The article is a report on development of forest scientific publication, which was discussed in a seminar arranged by the Finnish Society of Forest Science on 6th February, 1991. The article includes the presentations held in the seminar. 

  • Finnish Society of Forest Science, E-mail:
article id 5433, category Article
Marja-Leena Valkonen, Heikki Hänninen, Paavo Pelkonen, Tapani Repo. (1990). Frost hardiness of Scots pine seedlings during dormancy. Silva Fennica vol. 24 no. 4 article id 5433.
Keywords: Pinus sylvestris; frost hardiness; cold hardiness; annual cycle; chilling requirements; bud dormancy; rest
Abstract | View details | Full text in PDF | Author Info

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

The PDF includes an abstract in Finnish

  • Valkonen, E-mail: mv@mm.unknown (email)
  • Hänninen, E-mail: hh@mm.unknown
  • Pelkonen, E-mail: pp@mm.unknown
  • Repo, E-mail: tr@mm.unknown
article id 5431, category Article
Juha Siitonen. (1990). Potential forest pest beetles conveyed to Finland on timber imported from the Soviet Union. Silva Fennica vol. 24 no. 3 article id 5431.
Keywords: Finland; forest pests; timber trade; Scolytidae; Soviet Union; pest introduction; timber import
Abstract | View details | Full text in PDF | Author Info

Coniferous timber imported by rail from the Soviet Union in Finland was studied for the presence of potential forest and timber pest beetles. Systematic samples of fourteen lots of pine pulpwood were examined. Seven of the lots originated from the European parts of the Soviet Union and seven from Siberia. 23 species of Scolytidae and about 18 other phloeophagous species were found including three species new for Finland: Phaenops guttulata (Buprestidae), Ips subelongatus and Orthotomicus erosus (Scolytidae).

The PDF includes an abstract in Finnish.

  • Siitonen, E-mail: js@mm.unknown (email)
article id 5429, category Article
Hannu Mannerkoski, Veikko Möttönen. (1990). Maan vesitalous ja ilmatila metsäaurausalueilla. Silva Fennica vol. 24 no. 3 article id 5429.
English title: Soil water conditions and air-filled porosity on ploughed reforestation areas.
Original keywords: maanmuokkaus; turvemaat; maavesi; maaveden potentiaali; huokostilavuus; pohjavedenpinta; vesipotentiaali; metsäauraus; kivennäismaat
English keywords: site preparation; Finland; peatlands; soil moisture; ground water table; water potential; soil aeration; forest ploughing; mineral soil sites
Abstract | View details | Full text in PDF | Author Info

Five ploughed research areas from Finnish Norther Karelia were selected for comparison studies of plough ridges and untouched soil. Measurements were made at a depth of 10 cm in sample plots on both mineral and paludified mineral soil and peatland parts of these areas. In summer 1987 daily soil water matric potential was measured using tensiometers, and volumetric soil moisture content and density were determined from soil samples at two dates during the summer. Water characteristics of the core samples were also determined. On paludified mineral and peat soils the water table depth from the soil surface was measured.

The results indicated that in plough ridges matric potential was lowest. Plough ridges were also seen to dry and wet faster and to a greater degree than untouched soils. In untouched soils, soil water relations and aeration were not affected by the distance to the furrow. The effect of the plough ridge was smallest on peatland, where there was a good capillary connection from plough ridge to the ground water, if the ditches were not very effective. The soil in the ridges did not dry too much to restrict seedling growth. The untouched surface soil in poorly drained peat and paludified minear soil was, at least in a rainy growing season, often and also for long times so wet that 10% minimum air space required for good seedling root growth was not available.

The PDF includes an abstract in English.

  • Mannerkoski, E-mail: hm@mm.unknown (email)
  • Möttönen, E-mail: vm@mm.unknown
article id 5427, category Article
Matti Nuorteva. (1990). Salama puustokuolemien aiheuttajana. Silva Fennica vol. 24 no. 2 article id 5427.
English title: Lightning as a cause of death of tree groups.
Original keywords: metsätuhot; salaman isku; kuolleet puut
English keywords: forest damage; lightning
Abstract | View details | Full text in PDF | Author Info

The writer reports in this discussion article of four stands in Finland that have died due to a bolt of lightning. A death of a group of trees because of lightning has been relatively uncommon for the forest professionals. The trees may not have no lightning marks. The four sites are presented in detail. Characteristic for this type of death of trees is, for instance, that trees have died within a circular area (of usually 30 m of diameter), only conifers have died, trees die from the top down, sometimes marks can be found in trees in the centre of the area, and under the bark may be brown patches or stripes.

  • Nuorteva, E-mail: mn@mm.unknown (email)
article id 5426, category Article
Juhani Päivänen. (1990). Pohjoisen havumetsävyöhykkeen suot ja niiden metsätaloudellinen hyväksikäyttö. Silva Fennica vol. 24 no. 2 article id 5426.
English title: Peatlands of the boreal zone and their utilization in forestry.
Original keywords: metsätalous; metsäojitus; suot; soiden ojitus; havumetsävyöhyke
English keywords: forestry; peatlands; drainage of peatlands; boreal zone
Abstract | View details | Full text in PDF | Author Info

The paper is a review on utilization of peatlands in forestry in the countries of boreal zone: Finland, Norway, Sweden, Canada, the United States and the Soviet Union. First, the concept of peatlands, the types of peatlands throughout the zone are defined, and the use of natural peatlands is described. Finally, the drainage of peatlands for forestry purposes in the countries is reviewed. According to the statistics, a total of 13 million ha of peatlands have been drained in Fennoscandia and the Soviet Union.

  • Päivänen, E-mail: jp@mm.unknown (email)
article id 5421, category Article
Tiina Tonteri. (1990). Inter-observer variation in forest vegetation cover assessments. Silva Fennica vol. 24 no. 2 article id 5421.
Keywords: vegetation survey; forest vegetation; canopy-coverage estimation
Abstract | View details | Full text in PDF | Author Info

Differences in vegetation cover estimation by field biologists of the 8th National Forest Inventory in Finland were tested. Eleven observers estimated the canopy coverages of six forests taxa in 25 sample plots, located in one stand. The experiment was arranged after the field work. The coverage of Vaccinium vitis-idaea and the ground layer appeared to be the most difficult to estimate. The mean of the highest estimator was about double that of the lowest one. The least abundant species and the sample plots with the smallest coverages had the largest estimation errors. The most important compositional gradient of the data was natural, even though the test was made in a homogenous area. However, the effect of the observer could be recognized. The differences between observers could be caused by the differences both in visual estimation level and in placing the sampling frame. The results suggest that tests should always be made when several observers are used in vegetation surveys. If calibration is used, it should be made separately for each species.

The PDF includes an abstract in Finnish.

  • Tonteri, E-mail: tt@mm.unknown (email)
article id 5408, category Article
Olavi Laiho. (1990). Mykorritsat ja niiden vaikutus metsään. Silva Fennica vol. 24 no. 1 article id 5408.
English title: The significance of mycorrhizae to forest.
Original keywords: hapan sade; ilmansaasteet; mykorritsat; ektomykorritsat
English keywords: nitrogen; ectomycorrhiza; mycorrhiza; air pollution; acid rain; forest decline
Abstract | View details | Full text in PDF | Author Info

While the most common type of mycorrhizae is endomycorrhizae, ectomycorrhizae dominate in the case of coniferous trees. Pine, in particular, has a strong association with mycorrhizae. Mycorrhizae enable trees to take up water and nutrients much more efficiently than the roots themselves. The fungus, in return, obtain carbohydrates and is able to grow and fruit. Mycorrhizal fungi are probably numbered in their thousands but so far few are known. Knowledge about their physiology, in particular, is lacking and studies dealing with their isolation and inoculation, which may be commercially valuable, remain unpublished. A new challenge for mycorrhiza research is the effects of air pollution. Forest suffering from extensive air pollution have few mycorrhizal fungi., infection is weak and the number of root deformations is high. As good mycorrhizae are important to tree health, there is a particular need to intensify mycorrhiza research.

The PDF includes an abstract in English.

  • Laiho, E-mail: ol@mm.unknown (email)
article id 5404, category Article
Pentti Alho. (1990). Suomen metsittyminen jääkauden jälkeen. Silva Fennica vol. 24 no. 1 article id 5404.
English title: The history of forests in Finland after the last ice age.
Original keywords: puulajit; jääkausi; metsittyminen; luonnonhistoria
English keywords: tree species; review articles; natural afforestation; ice age; natural history; post glacial
Abstract | View details | Full text in PDF | Author Info

Based on literature this paper describes the natural afforestation of Finland that took place after the last ice age and the changes which have taken place during the last 10,000 years. The origin and development of the vegetation and trees are related to the changes in the edaphic and climatic factors. The first tree species to arrive in Finland were the primary colonizing species, birch and Scots pine. The appearance of Norway spruce dates back to about 5000 B.P. There have been great changes in the species composition of Finnish forests during the last several thousands of years but some 2,000–3,000 years ago the various species reached their present balance. The epoch of naural forests, which had lasted some 9,500 years, came to a conclusion, however, when man started to have a marked effect on the forest’s development 300–400 years ago.

The PDF includes an abstract in English.

  • Alho, E-mail: pa@mm.unknown (email)
article id 5403, category Article
Matti Leikola, Aune Koponen. (1990). Metsä Akatemiana. Silva Fennica vol. 24 no. 1 article id 5403.
English title: Forests as an academy - Professor Paavo Yli-Vakkuri 75 years.
Keywords: forest research; forest education; Paavo Yli-Vakkuri
Abstract | View details | Full text in PDF | Author Info

On 23th of March 1989 professor emeritus Paavo Yli-Vakkuri celebrated his 75th birthday. In 1963–1977 he acted as professor of silviculture and Head of the Department of Silviculture at the University of Helsinki. Due to his personality and positive attitude towards students and younger colleqaues, silviculture became the most popular subject for the graduate and postgraduate forestry students, and active research flourished at the Department of Silviculture during his era. This issue of Silva Fennica is dedicated to Paavo Yli-Vakkuri in gratitude and respect for his professional accomplishments in academic studies and research in forest sciences.

The PDF includes an abstract in English.

  • Leikola, E-mail:
  • Koponen, E-mail:
article id 5396, category Article
Matti Leikola. (1989). Uuteen maatalous- ja metsäakatemiaan. Silva Fennica vol. 23 no. 4 article id 5396.
English title: Towards new agriculture and forest academy .
Original keywords: metsäntutkimus; historia; maataloustieteet; tieteelliset seurat
English keywords: forest research; history; Finnish Society of Forest Science; scientific societies
Abstract | View details | Full text in PDF | Author Info

This paper is a commentary which summarises the history of the Finnish Society of Forest Science and its connection to the corresponding society in the field of agriculture, the Scientific Agricultural Society of Finland. The original idea when the Scientific Agricultural Society of Finland was founded was that the society would function as a scientific society for both forest scientists and agronomists. However, A.K. Cajander founded a separate academy for forest sciences. The article discusses the implications of this decision. 

  • Leikola, E-mail: ml@mm.unknown (email)
article id 5394, category Article
Pekka Kilkki. (1989). Kestävä metsätalous. Silva Fennica vol. 23 no. 4 article id 5394.
English title: Sustainable forest management.
Original keywords: metsänhoito; metsäekonomia; kestävä metsätalous
English keywords: forestry; sustainable forest management; forest economics
Abstract | View details | Full text in PDF | Author Info

This paper is a review on the development of sustainable forest management and what has been meant with the term in different times. The article summarises the birth of sustainable use of forests in the world and in Finland, and discusses sustainability in forest management, for instance from the point of view of one forest holding, large clearcuttings performed in Lapland, biological sustainability, business economics and overall planning.

  • Kilkki, E-mail: pk@mm.unknown (email)
article id 5393, category Article
Erkki Annila. (1989). Metsien kunto ja bioottiset tuhonaiheuttajat. Silva Fennica vol. 23 no. 4 article id 5393.
English title: Condition of forests and biotic damages .
Original keywords: metsätalous; hyönteistuhot; ilmastonmuutos; ilmansaasteet; sienituhot
English keywords: forestry; climatic change; insect damages; air pollution; fungal pathogens
Abstract | View details | Full text in PDF | Author Info

This review discusses whether forests are affected by biotic damages due to present or future environmental disturbances, and do environmental threats, such as air pollution and climatic change, weaken the condition of forest in a way that makes them vulnerable to damages by fungi and insect. The defence mechanisms of trees and factors affecting the development of an outbreak are described. Finally, the ways that air pollution and climatic change may affect biotic damages are discussed. 

  • Annila, E-mail: ea@mm.unknown (email)
article id 5386, category Article
Risto Päivinen, Hannu Yli-Kojola. (1989). Permanent sample plots in large-area forest inventory. Silva Fennica vol. 23 no. 3 article id 5386.
Keywords: forest inventory; sampling; permanent sample plots
Abstract | View details | Full text in PDF | Author Info

Theoretical and practical aspects of permanent sample plots are discussed in this paper. A study material of 6,871 permanent sample plots was generated using increment sample plots of the 7th National Forest Inventory of Finland. The effect of measurement errors and use of increment functions as ”a priori” information was studied via simulation experiments. The change in the growing stock volume between two consecutive measurement rounds was divided into the components drain, growth and mortality. Finally, a hypothetical inventory design using permanent sample plots was evaluated.

The PDF includes an abstract in Finnish.

  • Päivinen, E-mail: rp@mm.unknown (email)
  • Yli-Kojola, E-mail: hy@mm.unknown
article id 5381, category Article
Jouko Hämäläinen. (1989). Ajatuksia metsän arvon määrittämisestä. Silva Fennica vol. 23 no. 2 article id 5381.
English title: Thoughts about forest valuation.
Original keywords: metsänarvonlaskenta; korkokanta; summa-arvomenetelmä; diskonttausmenetelmä; kauppa-arvomenetelmä; kauppa-arvotaulukot
English keywords: forest valuation; rate of interest; market value tables
Abstract | View details | Full text in PDF | Author Info

In this article the methods of forest valuation, especially the sales value tables previously published in Finland are critically examined. In this connection attention is drawn to the rate of interest used in calculating the forest values.

The PDF includes an abstract in English.

  • Hämäläinen, E-mail: jh@mm.unknown (email)
article id 5380, category Article
Arto Rummukainen. (1989). Moreenimurskeella pinnoitettujen metsäteiden kunnossapito maataloustraktorikalustolla. Silva Fennica vol. 23 no. 2 article id 5380.
English title: Maintenance of crushed moraine paved forest roads with agricultural tractor implements.
Original keywords: metsätiet; kunnossapito; maataloustraktori; moreenimursketiet; hydraulinen tärytin; lana
English keywords: maintenance; forest roads; tractors; implements; grain-size distribution; vibrating blade; pulled drag
Abstract | View details | Full text in PDF | Author Info

The condition of forest road pavements was studied in spring, one week after maintenance and in autumn. The effect of vibrating blade was slightly better than that of pulled drag. Large loose stones couldn’t be pressed into pavement with either of the implements. The use of the vibrating blade was three times as expensive as the use of the pulled drag, however, the blade is suitable for other purposes as well.

The PDF includes an abstract in Finnish.

  • Rummukainen, E-mail: ar@mm.unknown (email)
article id 5372, category Article
Jussi Kuusipalo, Mari-Anna Berg, Marja Mikkola, Helena Niemensivu. (1989). A cross-sectional population survey on the consumption pattern of berries and berry products in Finland. Silva Fennica vol. 23 no. 1 article id 5372.
Keywords: wild berries; berries; berry products; consumption behaviour; garden berries; multiple use forestry
Abstract | View details | Full text in PDF | Author Info

The study is based on a questionnaire sent to 5,000 randomly sampled persons representing the adult population in Finland. The results give a picture of the amounts of berries preserved for home use and the consumption patterns of berries and berry products in the population and its various subgroups. Non-commercial berry consumption accounts for a considerable part of the total use of fruits and berries. However, use of berries and berry products decreases with the degree of urbanization and from older age classes to young. The results support the view that imported fruits and commercial juices are substitute products to domestic berries. It would appear that the consumer’s choice between fruits and berries is primarily regulated by the availability of berries.

The PDF includes an abstract in Finnish.

  • Kuusipalo, E-mail: jk@mm.unknown (email)
  • Berg, E-mail: mb@mm.unknown
  • Mikkola, E-mail: mm@mm.unknown
  • Niemensivu, E-mail: hn@mm.unknown
article id 5370, category Article
Harri Rantonen, Juhani Päivänen. (1989). Kasvatusmetsien metsänhoidollinen tila ojitusalueilla puunkorjuun jälkeen. Silva Fennica vol. 23 no. 1 article id 5370.
English title: Silvicultural condition of tree stands after thinning on drained peatlands.
Original keywords: metsänhoito; harvennushakkuu; puunkorjuu; turvemaat; ojitetut suot; harvennusvoimakkuus
English keywords: forest management; harvesting; forest drainage; silviculture; drained peatland; thinning intensity
Abstract | View details | Full text in PDF | Author Info

The area of stands studied by line plot survey was 594 ha. On the basis of the length of the inventory line the estimated proportion of harvesting strips was 14% and that of ditch openings 6% of the area. The calculated strip road spacing was 29 m. The option of the minimum diameter made it difficult to use the number of stems as criterion for thinning intensity. Thinning intensity evaluated according to the basal area had been stronger than recommended with low values of dominant height and milder with high values. The estimated removal according to stumps was 38 m3/ha on the average between the strips. The real removal has, however, been larger than that, as the strip road openings are made in connection with the first thinning.

The PDF includes an abstract in English.

  • Rantonen, E-mail: hr@mm.unknown (email)
  • Päivänen, E-mail: jp@mm.unknown
article id 5366, category Article
Pekka Ollonqvist. (1988). Resurssien jakautumisen tehokkuuden ja päätöksentekijöiden tavoitteiden mittauksessa tapahtuneista muutoksista metsäekonomiassa. Silva Fennica vol. 22 no. 4 article id 5366.
English title: The quarter century development in the paradigms of forestry economics.
Original keywords: tutkimus; metsätalous; metsäekonomia; päätöksenteko
English keywords: decision making; forestry; research; forest economics
Abstract | View details | Full text in PDF | Author Info

The two introductory books written by emeritus professor William Duerr provide an opportunity to scope the research progress in the forest economic discipline during almost a quarter century. This paper gives a presentation of the books (Fundamentals of Forest economics, 1960, and Forestry Economics as Problem Solving, 1984), and the development of forest economics during the period.

The PDF includes a summary in English.

  • Ollonqvist, E-mail: po@mm.unknown (email)
article id 5365, category Article
Pasi Puttonen. (1988). Metsänuudistamistutkimuksen arvioinnin seminaari 28.4.1988. Silva Fennica vol. 22 no. 4 article id 5365.
English title: Presentation report of evaluation group on forest regeneration research in Finland.
Original keywords: metsäntutkimus; metsänuudistaminen; Suomen Akatemia; arviointi
English keywords: evaluation; forest research; forest regeneration research; Academy of Finland
Abstract | View details | Full text in PDF | Author Info

The Academy of Finland commissioned a review of forest regeneration research. This paper summarises the evaluation. The report deals with the individual research projects and, in addition, the international evaluation group gives several recommendations to develop the forest regeneration research further. The recommendations concern education and training, publications, peer review, experimental design, routine work and extension service, and technology transfer. The paper also includes comments of the Finnish Forest Institute, the Finnish Society of Forest Science and a research scientist on the results of the evaluation.

The PDF includes a summary in English.

  • Puttonen, E-mail:
article id 5363, category Article
Veli Pohjonen, Timo Pukkala. (1988). Profitability of establishing Eucalyptus globulus plantations in the Central Highlands of Ethiopia. Silva Fennica vol. 22 no. 4 article id 5363.
Keywords: reforestation; Ethiopia; Eucalyptus globulus; simulation of growth; economic analysis; land use planning
Abstract | View details | Full text in PDF | Author Info

The economic analysis is based on computer simulations which covered a seedling rotation and three successive coppice rotations. Calculations were carried out for the four site productivity classes in Eucalyptus globulus plantations. The rotation length that maximized the land expectation value is 12–20 years for seedling rotation and 8–16 years for coppice rotations with discounting rates 2–8%. The mean wood production is over 40 m3/ha/a in the best site class and about 10 m3/ha/a in the poorest class with rotation lengths ranging from 10 to over 20 years. Thinnings increase the wood production and land expectation value by a few percentage points. In areas suitable to Eucalyptus globulus growth, the land expectation value is considerably higher in forestry than in agriculture, except in very poor areas or with very high rate of interest.

The PDF includes an abstract in Finnish.

  • Pohjonen, E-mail: vp@mm.unknown (email)
  • Pukkala, E-mail: tp@mm.unknown
article id 5362, category Article
Seppo Kellomäki, Heikki Hänninen, Taneli Kolström. (1988). Model computations on the impacts of the climatic change on the productivity and silvicultural management of the forest ecosystem. Silva Fennica vol. 22 no. 4 article id 5362.
Keywords: boreal forests; adaptation; simulation; climatic change; future silviculture; changing environment; pest management
Abstract | View details | Full text in PDF | Author Info

The model computations indicate that the climatic change in the form of higher temperatures and more precipitation could increase the productivity of the forest ecosystem and lead to higher rates of regeneration and growth. More frequent and intensive thinnings are needed to avoid the mortality of trees induced by accelerated maturation and attacks of fungi and insects. The climatic change could support the dominance of deciduous tree species and necessitate an intensification of the tending of seedling stands of conifers. The rise of air temperature during autumn and winter could change also the annual growth rhythm of trees and result in dehardening and subsequent frost damages and attacks of insects and fungi. The pest management could be the greatest challenge to the future silviculture, which could be modified most in Northern Finland.

The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Hänninen, E-mail: hh@mm.unknown
  • Kolström, E-mail: tk@mm.unknown
article id 5359, category Article
Olli Haltia, Markku Simula. (1988). Linkages of forestry and forest industry in the Finnish economy. Silva Fennica vol. 22 no. 4 article id 5359.
Keywords: forestry; Finland; employment; national economy; forest industries; input-output analysis; sectoral growth
Abstract | View details | Full text in PDF | Author Info

The purpose was to analyse the importance of forestry and forest industry in the Finnish economic development since the 1950’s, and to find out how the sector has contributed to the growth of the national economy through other sectors. Data were derived from the input-output tables of 1959, 1970 and 1980. Information provided by Hirschmanian linkages was expanded by taking into account e.g. induced, consumption, final demand and absorption linkages. The linkages of forestry and forest industry had multiplied during the study period. Both final demand linkages and intermediate product linkages were significant. The sector’s contribution to the development of metal and machinery and equipment industries as well as that of energy/water supply was significant. Integration with most other sectors has increased. Indirect production coefficients of forestry and forest industry were larger than on average in manufacturing. Because of labour productivity growth, production and employment coefficients were different.

The PDF includes an abstract in Finnish.

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

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

The PDF includes an abstract in Finnish.

  • Hänninen, E-mail: hh@mm.unknown (email)
  • Pelkonen, E-mail: pp@mm.unknown
article id 5349, category Article
Raphael E. L. Ole-Meiludie, Goodseldah K. Pamba. (1988). Time study on different techniques for nursery pot filling operation. Silva Fennica vol. 22 no. 2 article id 5349.
Keywords: productivity; time study; Tanzania; nursery pot filling; forest tree nursery
Abstract | View details | Full text in PDF | Author Info

Time study on different techniques in nursery pot filling operations at SUA Training Forest in Northern Tanzania was conducted. The results showed that improved tools and work place design significantly decreased the operation time, hence increased productivity. In addition, worker’s comfort was generally increased.

The PDF includes a summary in Finnish.

  • Ole-Meiludie, E-mail: ro@mm.unknown (email)
  • Pamba, E-mail: gp@mm.unknown
article id 5346, category Article
Timo Pukkala. (1988). Methods to incorporate the amenity of landscape into forest management planning. Silva Fennica vol. 22 no. 2 article id 5346.
Keywords: forest management; landscape management; multipurpose forestry; multiobjective planning; computer simulation; mathematical optimization; management plan
Abstract | View details | Full text in PDF | Author Info

The study presents methods that incorporate the amenity of a forest area into the management planning. The management plan is based on treatment schedules simulated for each compartment over the 20-year planning period. The best combination of treatment schedules is selected by multi-objective optimization. The amenity is divided into two parts: (1) within-stand amenity and (2) the amenity of landscape when viewed afar (distant scene). The within-stand amenity is expressed in terms of adjective sum which is estimated from stand characteristics. The adjective sum of the whole area in a selected year can be taken as an objective or constraining variable of optimization. The assessment of the distant scene is based on computer illustrations which show the predicted temporal change of landscape according to a particular management plan.

The PDF includes a summary in Finnish.

  • Pukkala, E-mail: tp@mm.unknown (email)
article id 5345, category Article
Leo Koutaniemi, Raimo Koponen, Kyösti Rajanen. (1988). Podzolization as studied from terraces of various ages in two river valleys, Northern Finland. Silva Fennica vol. 22 no. 2 article id 5345.
Keywords: boreal forest; Finland; Lapland; nutrient concentration; podzol; podzolization; taiga
Abstract | View details | Full text in PDF | Author Info

The study was made in the Ivalojoki and Oulankajoki valleys, consisting of terraces of well sorted sandy material aged 9500–300 B.P. The vegetation is characterized by dry and moderately dry forest types with Scots pine (Pinus sylvestris L.) as the dominant tree species. The study included: forest types, particle size and sorting of mineral horizons, thickness of horizons, amount of organic material, pH, electrical conductivity, and NH4OAc (pH 4.56) extractable Fe, Al, P, K, Mg, Mn and Zn concentrations. The principal aim was to study the interrelationships between all these properties with special reference to the age of the soil.

The results allowed a distinction to be made between the following categories: (1) features typical of podsolization (e.g. increase in leaching of Fe and Al with age of soil from the A2), (2) certain factors showing higher values in the north (Ivalo) than in the south (Oulanka), principally Fe and Mg, (3) declining trends in P, Mg, Mn and Zn concentrations with age, which may partly be due to the geological history, and (4) declining trends in amount of organic material and electrical conductivity with age, these both being factors arising from the geological history rather than from podzolization.

The PDF includes a summary in Finnish.

  • Koutaniemi, E-mail: lk@mm.unknown (email)
  • Koponen, E-mail: rk@mm.unknown
  • Rajanen, E-mail: kr@mm.unknown
article id 5342, category Article
Ilari Lumme, Timo Törmälä. (1988). Selection of fast-growing willow (Salix spp.) clones for short-rotation forestry on mined peatlands in northern Finland. Silva Fennica vol. 22 no. 1 article id 5342.
Keywords: biomass production; breeding; Salix spp.; short-rotation forestry; willows; Salix viminalis; Salix myrsinifolia; winter hardiness; clone selection; mined peat areas
Abstract | View details | Full text in PDF | Author Info

Possibilities of developing suitable willow (Salix spp.) clones for short-rotation forestry on mined peatlands in the north-western area of Finland were studied in a field experiment in which 300 willow clones were tested during 1985–87. Most of the tested clones started to grow from cuttings on limed and fertilized peat soil. Salix viminalis L. clones of southern origin had a higher leafless above ground biomass production than the well adapted control clone and the local Finnish willows, but their winter hardiness was not satisfactory. The growth habit of some southern willows was also better than that of the control clone. It was also possible to select clones with good sprouting capacity. There were few Salix myrsinifolia Calisb. clones of Finnish origin, which had better cold tolerance than all other willows tested and higher biomass production than that of the control clone. The most critical factor to be selected for this is the optimal combination of winter hardiness and biomass production. This is attempted by selecting clones on the basis of this experiment for a breeding program.

The PDF includes a summary in Finnish.

  • Lumme, E-mail: il@mm.unknown (email)
  • Törmälä, E-mail: tt@mm.unknown
article id 5341, category Article
Hannu Hökkä, Jukka Laine. (1988). Suopuustojen rakenteen kehitys ojituksen jälkeen. Silva Fennica vol. 22 no. 1 article id 5341.
English title: Post-drainage development of structural characteristics in peatland forest stands.
Original keywords: metsikön rakenne; turvemaat; ojitetut suot; eri-ikäisrakenne; runkoluku; läpimittajakauma
English keywords: stand structure; drained peatlands; diameter distribution; forest drainage; uneven-aged structure
Abstract | View details | Full text in PDF | Author Info

The effect of drainage on structure of tree stands is analysed by comparing the average structural characteristics (e.g. diameter distribution) of stands in the data for different drainage age classes and selected site types. The material consists of ca. 4,400 relascope sample plots, which are part of a large drainage area inventory project. The uneven-aged structure of the virgin peatland forest is preserved for several decades after drainage. This is enhanced by the post-drainage increase of small-diameter trees, especially birch. The number of trees per hectare increased during a period of ca. 30 years and levelled off thereafter. The increase in the number of saw log stems is clearly related to the fertility of the site and its geographical location.

The PDF includes a summary in English.

  • Hökkä, E-mail: hh@mm.unknown (email)
  • Laine, E-mail: jl@mm.unknown
article id 5340, category Article
Martti Saarilahti. (1988). Development in techniques for studying forest roads on peatlands. Silva Fennica vol. 22 no. 1 article id 5340.
Keywords: moisture content; peatlands; bearing capacity; settlement; forest roads; measurement methods; subsurface profiling; microwave
Abstract | View details | Full text in PDF | Author Info

A light seismic method, a short-pulse radar and a microwave probe are tested in assessing the properties of a forest road constructed on peatland. The light seismic method gave reliable values for estimating the bearing capacity of the road. It was found that bearing capacity was mostly dependent on embankment thickness, but quality of fabric might also have an influence. Embankment thickness and peat depth can be measured on the radiogram, and some additional information on road bed and peat obtained. The microwave peat probe permits recording of the continuous moisture profile in situ, which improves accuracy of planning.

The PDF includes a summary in Finnish.

  • Saarilahti, E-mail: ms@mm.unknown (email)
article id 5337, category Article
Pekka Hako. (1987). Musiikki, metsä ja ihminen. Silva Fennica vol. 21 no. 4 article id 5337.
English title: Music, forest and man.
Original keywords: kulttuuri; metsä; identiteetti; musiikki
English keywords: Finnish identity; symbolism; forest music
Abstract | View details | Full text in PDF | Author Info

In Finnish music national forests and international urban culture meet in an original way. Around the last turn of century, composers believe they had discovered their spiritual roots in nature and especially in the forests. The universal musical language of Jean Sibelius, for example, is based on a deep Finnish identity, the atmosphere of Kalevala. Sibelius’ Tapiola is, thus, among our century’s most powerful musical interpretations of feelings about nature. Nature inspired music is, generally, associated with such positive qualities as beauty, peace, softness, light and joy. A great deal of forest music is based on literature, where natural images have almost always had a positive interpretation.
The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Hako, E-mail: ph@mm.unknown (email)
article id 5336, category Article
Pekka Virtanen. (1987). Kansanperinteen metsäkuvia. Silva Fennica vol. 21 no. 4 article id 5336.
English title: The forest in Finnish folk lore.
Original keywords: kansanperinne; metsähistoria; metsäperinne
English keywords: forest history; folklore; forest traditions
Abstract | View details | Full text in PDF | Author Info

Several views to forest’s role in the Finnish folklore are presented. They clearly show how many important dimensions forests have had in Finnish life. Descriptions concentrate on forest-related traditions of ancient times. They give a basis to examining the role of forests in the modern Finnish mind.

The paper is based on a lecture given in the seminar 'The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Virtanen, E-mail: pv@mm.unknown (email)
article id 5335, category Article
Juhani Pallasmaa. (1987). Metsän arkkitehtuuri. Silva Fennica vol. 21 no. 4 article id 5335.
English title: The architecture of the forest.
Original keywords: maisema; arkkitehtuuri; kansallisromantiikka; funktionalismi; kaupungit; metsäkaupunki
English keywords: forest; landscape; architecture; national romanticism; functionalism; towns; garden city
Abstract | View details | Full text in PDF | Author Info

The paper presents aspects of town and forest architecture. A feature of the Finnish building tradition is that the forest is allowed to grow next to buildings. After the Second World War a new type of town was created in Finland, ”the forest town”. The most prominent feature of the history of Finnish architecture, from national romanticism to functionalism and up to the present day, is the modification of international ideals to a certain ”forest culture” style.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Pallasmaa, E-mail: jp@mm.unknown (email)
article id 5334, category Article
Aimo Reitala. (1987). Metsä suomalaisessa kuvataiteessa. Silva Fennica vol. 21 no. 4 article id 5334.
English title: Forests in Finnish art.
Original keywords: maisema; metsä; kuvataide; kansallisromantiikka
English keywords: forest; landscape; identity; art; realism; national romanticism
Abstract | View details | Full text in PDF | Author Info

The Finnish forest was elevated into an appreciated artistic motif by Werner Holmberg with his picture ”The Finnish conifer forest” in 1858. The second significant period was during national romanticism in the 1980’s, when the decorative beauty of the winter forests was discovered. At the turn of the century, the forest obtained a central national symbolic significance, and many leading artists regarded increased cuttings as a rape of the forests. Since that period, individual artists have succeeded in bringing new features in the art history of our forests.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Reitala, E-mail: ar@mm.unknown (email)
article id 5333, category Article
Pekka Suhonen. (1987). Metsä ja kirjallisuus. Silva Fennica vol. 21 no. 4 article id 5333.
English title: Forest and literature.
Original keywords: kirjallisuudentutkimus; metsäkirjallisuus; metsästyskirjallisuus; savottakirjallisuus; metsästysrunot; mytologia
English keywords: literary science; forest literature; logger literature; hunting literature; hunting poems; mythology
Abstract | View details | Full text in PDF | Author Info

In world literature, there are many forests of significance, e.g. oak forest of Mamre and in Dante’s Divine Comedy. Finnish literature has abounded with forest topics since ancient folkore. We have a literature of floaters, loggers and paper workers of industrialized Finland, not to speak of a hunting literature. A major theme is ”from forest to town”, where the first work, Aleksis Kivi’s ”Seven brothers”, is a landmark in Finnish literature. Forests of many other authors are also presented, as well as ancient chants and poems.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Suhonen, E-mail: ps@mm.unknown (email)
article id 5332, category Article
Aarne Reunala. (1987). Metsä arkkityyppinä. Silva Fennica vol. 21 no. 4 article id 5332.
English title: Forest as an archetype.
Original keywords: metsätalous; metsä; kansanperinne; aineettomat arvot; symboliikka
English keywords: forestry; forest; folklore; archetypes; folk tradition; symbolism; intangible values
Abstract | View details | Full text in PDF | Author Info

According to universal primitive beliefs, there was a huge pole or tree in the centre of the universe to support the sky. These beliefs gave rise to innumerable customs where both trees and wood have been used to promote health and good luck. Even today, many such customs exist: the Christmas tree, maypole, Midsummer birches, birch whisks in the Finnish sauna, ritual tree plantings etc. In addition to the tree, also the forest as both a protecting and a frightening maternal symbol can be considered as an archetype. Intensive forestry diminishes the archetypal contents of forests, which may be one reason behind critical attitudes towards modern forestry.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Reunala, E-mail: ar@mm.unknown (email)
article id 5331, category Article
Pirkko Siltala. (1987). Metsän turvallisuus. Silva Fennica vol. 21 no. 4 article id 5331.
English title: The security of the forest.
Original keywords: metsä; turvallisuudentunne; kokemus
English keywords: forest; sense of safety; experience
Abstract | View details | Full text in PDF | Author Info

The security provided by forests is approached through various authors’ descriptions and through psychotherapeutic experience. The lap of the forest can recreate early security, protection and unity, for example the lap of mother or father. The forest is also a safe place to externalize inner feelings, desires, fears and erotic images. Intensive forest management and air pollution are nowadays threatening the protective role of forests.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Siltala, E-mail: ps@mm.unknown (email)
article id 5330, category Article
Pirkkoliisa Ahponen. (1987). Metsä elämäntavassa. Silva Fennica vol. 21 no. 4 article id 5330.
English title: The forest in way of life studies.
Original keywords: metsä; elämäntapa; suomalaisuus; luontosuhde; elämäntapatutkimus
English keywords: forest; way of life; finnishness; relationship with nature; sociological studies
Abstract | View details | Full text in PDF | Author Info

Sociological studies on the way of life tell rather little about the impact of forests on Finn’s everyday life. The change of life styles, urbanization and middle-class values, signify a detachment from immediate and practical relationship with nature. Those born in the countryside conserve their relationship with nature in their leisure activities, but the urban-born generation needs the mass-media, education, travel and other institutions in order to maintain and develop its relationship with nature.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Ahponen, E-mail: pa@mm.unknown (email)
article id 5327, category Article
Yrjö Sepänmaa. (1987). Metsäestetiikka ja metsän estetiikka. Silva Fennica vol. 21 no. 4 article id 5327.
English title: Forstästhetik and forest aesthetics.
Original keywords: metsänhoito; estetiikka; kulttuurimetsä; luonnonmetsä; symboliarvo
English keywords: natural forest; silviculture; aesthetics; cultural forest; symbol value
Abstract | View details | Full text in PDF | Author Info

Forstästhetik is a programme for forest management, resembling an art manifesto. Forest managers are programme executors. Forest aesthetics is forest investigation from the point of view of beauty. In the case of managed forests, it is possible to ask, what is the manager’s programme and his skill to achieve personal solutions. In forests, the functioning and sustainability of the ecosystem are basic principles affecting all other values. On this basis it is possible to evaluate the competence of taste systems and the logic of their application.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Sepänmaa, E-mail: ys@mm.unknown (email)
article id 5326, category Article
Matti Linkola. (1987). Metsä kulttuurimaisemana. Silva Fennica vol. 21 no. 4 article id 5326.
English title: The forest as a cultural landscape.
Original keywords: kaskiviljely; asutus; metsämaisema; kulttuurimaisema; metsälaidunnus
English keywords: forest landscape; cultural landscape; slash-and-burn cultivation; land occupation; forest grazing
Abstract | View details | Full text in PDF | Author Info

The main features of the Finnish landscape are a result of preglacial erosion processes and the structural lines of the bedrock. The microstructure of the landscape was created by the Ice Age and its melting processes. Upon this base, human activities have created a palimpsest of cultural landscapes. The article describes the effects of slash-and-burn cultivation, tar production, cattle ranging and some other forest uses to the forest landscape. 

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Linkola, E-mail: ml@mm.unknown (email)
article id 5325, category Article
Eero Julkunen, Altti Kuusamo. (1987). Kansallis/omaisuus. Metsän mielikuvat isänmaallisissa lauluissa ja metsämainoksissa. Silva Fennica vol. 21 no. 4 article id 5325.
English title: Images of forests in patriotic songs and forest advertisements.
Original keywords: semiotiikka; populaarikulttuuri; suomalainen identiteetti; isänmaalliset laulut; metsämainokset
English keywords: semiotics; popular culture; Finnish identity; patriotic songs; forest advertisements
Abstract | View details | Full text in PDF | Author Info

The article compares forest images in provincial and patriotic songs and in forest advertisements by banks and insurance companies. In songs, coniferous forests represent the primaeval nature and broadleaved forests represent culture. Coniferous forest is the real patriotic forest. Forest images in advertisements are twofold: both elevated patriotic forests and profane raw-material forests are found.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Julkunen, E-mail: ej@mm.unknown (email)
  • Kuusamo, E-mail: ak@mm.unknown
article id 5324, category Article
Jussi Raumolin. (1987). Metsän suojassa. Silva Fennica vol. 21 no. 4 article id 5324.
English title: Under the shelter of forests: some thoughts about political anthropology and the geopolitics of forests.
Original keywords: metsät; poliittinen antropologia; geopolitiikka; sotahistoria; sissisodankäynti
English keywords: state formation; geopolitics; guerilla warfare; forest warfare; political anthropology
Abstract | View details | Full text in PDF | Author Info

Only a few studies exist concerning the political anthropology and geopolitics of forests. The role of forests in European geopolitics and their role in restraining concentration of power and promoting guerrilla warfare is examined. The shelter of forest cover has been a fundamental factor for the formation of the Finnish people and it has also played an important role in the defence of independent Finland. Clearcuttings, forest roads and modern reconnaissance technology have recently diminished the protective shelter of forests.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Raumolin, E-mail: jr@mm.unknown (email)
article id 5322, category Article
Juhani Pietarinen. (1987). Ihminen ja metsä. Silva Fennica vol. 21 no. 4 article id 5322.
English title: Man and the forest.
Original keywords: asenteet; metsä; utilismi; mystisismi; humanismi; primitivismi
English keywords: forest; attitudes; utilitarism; humanism; primitivism; mysticism
Abstract | View details | Full text in PDF | Author Info

Four basic attitudes towards forests are distinguished: In utilitarianism the forest is seen merely as a means of increasing the standard of living. Humanism strives for the forest use in the service of educational ideals. Mysticism aims at an immediate experience of unity between man and nature. Primitivism denies all human privileges in nature. These attitudes describe that multiple relations exist between man and forest. An essential question is which attitude can best be defended.

The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.

  • Pietarinen, E-mail: jp@mm.unknown (email)
article id 5321, category Article
Aarne Reunala, Pekka Virtanen. (1987). Metsä suomalaisten elämässä. Silva Fennica vol. 21 no. 4 article id 5321.
English title: The forest as a Finnish cultural entity.
Original keywords: maisema; seminaari; kulttuuri; metsä; identiteetti; symboli; kansanperinne
English keywords: forest; landscape; seminar; culture; identity; symbol; folklore
Abstract | View details | Full text in PDF | Author Info

This publication consists of 16 papers on importance of forests to Finns, mainly from the viewpoint of various social and humanistic sciences. The articles are based on lectures given to a seminar organized in Helsinki, December 18-19, 1986.

This paper includes preface and list of the speeches in English.

  • Reunala, E-mail:
  • Virtanen, E-mail:
article id 5320, category Article
Veikko Hintikka. (1987). Germination ecology of Galeopsis bifida (Lamiaceae) as a pioneer species in forest succesion. Silva Fennica vol. 21 no. 3 article id 5320.
Keywords: prescribed burning; Galeopsis bifida; germination ecology; pioneer species; forest succession; release of seed dormancy; clear-cut area
Abstract | View details | Full text in PDF | Author Info

The occurrence of Caleopsis bifida on clear-cut and burned forest soil and its disappearance in 4–6 years after disturbance is attributed to its germination ecology. Initially the seeds are dormant 96–100% and remain dormant in nylon gaze bags in different types of forest humus layers at least 10 years. Dormancy is released in laboratory (1) by treatment of 100 ppm aqueous solution of GA3, (2) by heating the dormant seeds to 40–55°C for 1–5 h, and (3) by 1% KNO3 solution. It is concluded that conditions in clear-cut and burned areas favour germination of seeds in regard to temperature and content of nitrates in contrast to humus of closed vegetation where the seeds remain dormant.

The PDF includes an abstract in Finnish.

  • Hintikka, E-mail: vh@mm.unknown (email)
article id 5319, category Article
Heikki Hänninen. (1987). Effects of temperature on dormancy release in woody plants. Silva Fennica vol. 21 no. 3 article id 5319.
Keywords: temperature; bud burst; dormancy; annual cycle of development; dormancy breaking; chilling requirement; rate of development; rest period; simulation model; stage of development
Abstract | View details | Full text in PDF | Author Info

Logical structure of three simulation models and one conceptual model concerning effects of temperature on dormancy release in woody plants was examined. The three basic types of simulation models differed in their underlying assumptions. Contrasting implications of the models were inferred by deduction. With the aid of these implications, the model types can be tested using experiments with continuous and interrupted chilling. Similarly, implications of the conceptual model of rest phases were inferred, by which the model can be tested using experiments with continuous chilling and forcing in multiple temperatures. The possibilities to synthetize the conceptual model with any of the three simulation model types, as well as the biological interpretation of the model variables, were discussed.

The PDF includes an abstract in Finnish.

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

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

The PDF includes an abstract in Finnish.

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

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

The PDF includes an abstract in Finnish.

  • Kellomäki, E-mail: sk@mm.unknown (email)
  • Seppälä, E-mail: ms@mm.unknown
article id 5314, category Article
M. Saarilahti, E. Bakena, G. Mboya, T. Minja, T. Ngerageze, J. Ntahompagaze. (1987). Studies on Tanzanian forest work. Silva Fennica vol. 21 no. 2 article id 5314.
Keywords: logging; time study; heart rate; work load; forest work; production rate; Africa; performance rating; manual timber cutting; sulky skidding; energy expenditure
Abstract | View details | Full text in PDF | Author Info

Four teams of two workers were time-studied in clearcutting of a cypress plantation and three teams in sulky skidding. The heart rate was recorded every 30 s. The average heartrate in timber cutting was 117.5 ± 13.4 P/min, and it was mainly dependent on worker’s working capacity. Average work load index was 41 ± 3% when working at 97% performance. The production rate was then 2.5 m3/h (crew). In sulky skidding the heart rate was lower, 106 ± 1.1 P/min, as well as the work load (WLI 30 ± 1%) and performance rating (87%). The low production rate (1.1 m3/h) (crew)) over 45 m distance is mainly due to under-dimensioned load size. The energy expenditure in timber cutting was 21.4 kJ/min and in sulky skidding 16.3 kJ/min. Daily energy expenditure was 15.0 MJ/d, and most of the timber cutters belonged to the class ”exceptionally active”.

The PDF includes an abstract in Finnish.

  • Saarilahti, E-mail: ms@mm.unknown (email)
  • Bakena, E-mail: eb@mm.unknown
  • Mboya, E-mail: gm@mm.unknown
  • Minja, E-mail: tm@mm.unknown
  • Ngerageze, E-mail: tn@mm.unknown
  • Ntahompagaze, E-mail: jn@mm.unknown
article id 5313, category Article
Pentti Lähteenoja. (1987). Effects of forestry extension courses. Silva Fennica vol. 21 no. 2 article id 5313.
Keywords: forestry; forest owners; private forestry; extension activities; forest advisory service
Abstract | View details | Full text in PDF | Author Info

The attitudinal, behavioural and cognitive effects of four forestry extension and training courses were evaluated. The courses produced positive effects on the participants’ forestry knowledge. Further new forestry skills were adopted, and the courses had some positive behavioural effects. The attitudinal effects of the courses were mainly inconclusive. Differences between the evaluated courses were remarkable.

The PDF includes an abstract in Finnish.

  • Lähteenoja, E-mail: pl@mm.unknown (email)
article id 5309, category Article
Veli Pohjonen. (1987). Salix "Aquatica Gigantea" and Salix x dasyclados Wimm. in biomass willow research. Silva Fennica vol. 21 no. 2 article id 5309.
Keywords: biomass; short rotation forestry; Salix spp.; willow systematics; Salix 'Aquatica Gigantea'; Salix burjatica; Salix x dasyclados
Abstract | View details | Full text in PDF | Author Info

Salix 'Aquatica Gigantea', widely experimented and promising species for temperate zone short rotation forestry, has since 1950 recorded in Finland 23 times with different clone numbers. Salix x dasyclados Wimm., by morphological, cultivational and productivity characteristics similar willow has been recorded 16 times.

The nomenclature and origin of both willows have remained unclear in field research. Recent observations, based on morphological analyses and chromosome studies suggest that ’Aguatica gigantea’ and most S. x dasuclados clones can be collected under one Siberian species: Salix burjatica Nasarov. The true Salix x dasyclados Wimm. is a female hybrid S. x viminalis x cinerea, famous West-European basket willow that has been very little experimented in Finland.

The PDF includes an abstract in Finnish.

  • Pohjonen, E-mail: vp@mm.unknown (email)
article id 5308, category Article
Martti Saarilahti, R. E. L. Ole-Meiludie. (1987). Production rate and work strain on workers in cutting of pines in Tanzania. Silva Fennica vol. 21 no. 1 article id 5308.
Keywords: logging; forest work; physical stress; Tanzania; payment system; production rate
Abstract | View details | Full text in PDF | Author Info

A team of 2 experienced workers was time-studied and their heart rate recorded under 4 days in clearcutting of a highly self-pruned Pinus patula Schltdl. & Cham. plantation. Task work and bonus payment systems were compared, but there was no difference in production rate, only the workplace time was extended from 2.3 h/d in task work to 3.9 h/d in bonus payment. The heart rate was 115–116 P/min in felling, 105–109 P/min in debranching and 109–114 P/min in bucking. The average heart rate in timber cutting was 108–109 P/min. Work load index was 34–37%, and the workers did not show any symptoms of accumulated stress. The production rate was 3.2 m3/h, (WPT, crew), which corresponds average piecework rate, the comparable walking speed being about 6.0 km/h. There are possibilities to increase the daily task by ergonomic grounds.

The PDF includes an abstract in Finnish.

  • Saarilahti, E-mail: ms@mm.unknown (email)
  • Ole-Meiludie, E-mail: ro@mm.unknown
article id 5307, category Article
Simo Poso, Raito Paananen, Markku Similä. (1987). Forest inventory by compartments using satellite imagery. Silva Fennica vol. 21 no. 1 article id 5307.
Keywords: forest inventory; stand characteristics; remote sensing; Landsat 5 TM; forest inventory and monitoring; two phase sampling; ancillary information
Abstract | View details | Full text in PDF | Author Info

A method for using satellite data in forest inventories and updating is described and tested. The stand characteristics estimated by the method showed high correlation with the same characteristics measured in the field. The correlation coefficients for volume, age and mean height were about 0.85. It seems that the method is applicable to practical forestry. Extensive work in programming, however, is required.

The PDF includes an abstract in Finnish.

  • Poso, E-mail: sp@mm.unknown (email)
  • Paananen, E-mail: rp@mm.unknown
  • Similä, E-mail: ms@mm.unknown
article id 5301, category Article
Birger Solberg. (1986). Forest sector simulation models as methodological tools in forest policy analysis. Silva Fennica vol. 20 no. 4 article id 5301.
Keywords: forest policy; Norway; simulation models; forest sector models; forest policy analysis
Abstract | View details | Full text in PDF | Author Info

The usefulness of forest sector models in forest policy analysis is discussed, mainly based on experiences from Norway. Forest sector modelling is contrasted to two alternative approaches: (i) Intuitive, verbal analysis, and (ii) econometric models. It is concluded that forest sector models, properly developed in contact with the policy makers, should be of considerable value in forest policy analysis.

  • Solberg, E-mail: bs@mm.unknown (email)
article id 5300, category Article
Takuro Kishine. (1986). Optimizing simulation model on forest policy. Silva Fennica vol. 20 no. 4 article id 5300.
Keywords: forest policy; forestry; welfare; environment; Japan; simulation system model; policy formation
Abstract | View details | Full text in PDF | Author Info

This paper designs an Economy-Welfare-Environment Adjustment System model (EWEAS model or EWE model in short) which consists of the circular flow of the economic, the welfare, and the environment system of forestry. That is, this model builds the relationship between the systems for material wealth and that for mental wealth.

The EWE model is designed as a complete open system model which describes the economy-welfare-environment circular system in forestry by linking up the internal system of forestry with the surrounding external systems. The EWE model can be manipulated as a policy formation or a policy decision model, and it is available for policy evaluation in the economic, the welfare and the environmental phase of forestry. The model is a basic simulation system model which is reliable in its reproductive fitness, stability and universality. Thus, this model ought to be useful in any country in the world as well as in Japan.

  • Kishine, E-mail: tk@mm.unknown (email)
article id 5299, category Article
Shigeru Shimotori. (1986). Private and municipal forests and the forestry planning system in Japan - trends and problems after World War II. Silva Fennica vol. 20 no. 4 article id 5299.
Keywords: forest management; forest owners; forest resources; private forestry; Japan; forestry policy; forestry planning system
Abstract | View details | Full text in PDF | Author Info

In this paper, the author explains the characteristics of the Japanese forestry planning system and points out some of the problems found therein from the viewpoint of the management of privately-owned forests relating to the economic background and governmental policy.

The forestry planning system is a centralizes type of planning, the planning begins at the top and flows downward and outward the periphery. In order to make this planning system an effective instrument, the district forestry planning founded under the system must approach the problem of how to combine the resources of the forest with the district’s inhabitants and the forest owners; and further, the extent of the effective union of the district and the local timber manufacturing must be examined.

  • Shimotori, E-mail: ss@mm.unknown (email)
article id 5298, category Article
Frederick W. Cubbage, Donald G. Hodges. (1986). Public and private technical assistance programs for non-industrial private forest landowners in the southern United States. Silva Fennica vol. 20 no. 4 article id 5298.
Keywords: forest management; forest policy; private forestry; United States; forest extension; forest advisory services; forest consulting; forest management plans; supervision
Abstract | View details | Full text in PDF | Author Info

Non-industrial private landowners hold about two-thirds of the forest land in the southern United States. The types of public (state) and private (consulting and industrial) assistance offered to these owners is reviewed. In total, about 1,600 foresters in the South provide management assistance to non-industrial private forest owners. They assist at least 72,000 owners annually, including provision of management plans for about 10 million acres and supervision of over 4 million acres of leased lands.

  • Cubbage, E-mail: fc@mm.unknown (email)
  • Hodges, E-mail: dh@mm.unknown
article id 5297, category Article
P. A. Harou. (1986). The EC context for private forestry incentive evaluation. Silva Fennica vol. 20 no. 4 article id 5297.
Keywords: forest policy; evaluation; European Community; forestry incentives
Abstract | View details | Full text in PDF | Author Info

A brief overview of forestry in European Community (EC) of the 9 is presented. Forestry incentives seem necessary for increasing timber production on private ownership in order to avoid possible price inflation.

In the economic analysis of the program evaluation method proposed here to assess the efficiency of such incentives, a broad EC perspective is recommended to avoid erroneous conclusion. The evaluation made from the prospect of a member country only is artificial and is influenced by EC policies anyway. The evaluation changes depending on whether these EC policies are considered given and immutable or not.

  • Harou, E-mail: ph@mm.unknown (email)
article id 5296, category Article
Russell K. Henly, Paus V. Ellefson. (1986). Cost and effectiveness of legal mandates for the practice of forestry on private land. Silva Fennica vol. 20 no. 4 article id 5296.
Keywords: forest management; forest policy; forest legislation; private forestry; United States; forest laws; regulation of forest practices; protection of forest resources
Abstract | View details | Full text in PDF | Author Info

Comprehensive state laws regulating the practice of forest management on private lands are in effect in seven of the United States. Established to protect a wide range of non-timber forest resources and to ensure reforestation after harvest, these laws may impose significant administrative costs on states and significant compliance costs on landowners and timber operators. Total state administration costs for 1984 are estimated at $10.1 and total private sector compliance costs are estimated at $120.5 million, for a total regulation cost of $130.6 million.

The resource protection effectiveness of state forest practice regulation is difficult to quantify. However, agreement is strong that regulation has led to significant improvements in forest resource conditions and has helped to increase reforestation.

  • Henly, E-mail: rh@mm.unknown (email)
  • Ellefson, E-mail: pe@mm.unknown
article id 5295, category Article
J. E. de Steiguer, J. P. Royer. (1986). Increasing forestry investments by means of public policy programs. Silva Fennica vol. 20 no. 4 article id 5295.
Keywords: forest policy; forest owners; timber supply; timber prices; nonindustrial private forestry; timber demand; NIPF behaviour
Abstract | View details | Full text in PDF | Author Info

In 1979, the Federal Research in the United States instituted a so-called ”tight money” policy which led to a decrease in the demand for stumpage. The decrease in demand brought about lower stumpage prices and, consequently, a waning interest in policies to stimulate NIPF production. The authors report on five recent studies on NIPF behaviour and raise concerns that increases in demand for housing may bring new pressure upon NIPF as a source of wood.

  • Steiguer, E-mail: js@mm.unknown (email)
  • Royer, E-mail: jr@mm.unknown
article id 5294, category Article
Gordon D. Lewis. (1986). The role of policy in forest resource development. Silva Fennica vol. 20 no. 4 article id 5294.
Keywords: forest policy; sustainable forestry; forest resources; social forestry; exploitation; resource protection; natural resource development
Abstract | View details | Full text in PDF | Author Info

A nation that wishes to enhance its social and economic well-being through more intensive utilization of its forest resources must develop a rather comprehensive policy statement to ensure that the expanded exploitation does not lead to the destruction of these resources. The policy must specify the goals to be achieved, provide general direction on how these goals can be achieved, and develop a system of checks-and-balances to ensure achievement of the long-term objectives. The policy must consider resource protection, the economic needs at the various levels of government, the social impacts of utilization on ways of life in all areas of the nation, and the infrastructure needed in the short and long terms.

  • Lewis, E-mail: gl@mm.unknown (email)
article id 5293, category Article
Claude Gendreau. (1986). Historical considerations and evolution of the forest policies for small woodlot owners of Quebec. Silva Fennica vol. 20 no. 4 article id 5293.
Keywords: forest management; forest policy; Canada; non-industrial forest owners; private forestry; forest programs; timber marketing; small-woodlot forestry
Abstract | View details | Full text in PDF | Author Info

In order to understand the present forest policies for the small woodlot of Quebec, it is essential to understand the history of settlement of Quebec. Following this brief description, the author introduces the various forest policies (programs) which have been initiated in Quebec by various levels of governments in order to deal with the management of these lands.

  • Gendreau, E-mail: cg@mm.unknown (email)
article id 5292, category Article
Ryoichi Handa. (1986). On the principles of Japanese forest policy since 1950. Silva Fennica vol. 20 no. 4 article id 5292.
Keywords: forest policy; forestry; timber supply; timber production; history; Japan
Abstract | View details | Full text in PDF | Author Info

In Japan many governmental projects have been promoted during 35 years since 1950, which were most active in the history of our forestry and wood industry. They were pushed forward for and by high economic growth. This article refers to the development of our forest policy and projects in those days. But as for the future of the forest economics, it is an urgent question to develop the comparative study between every nation’s experience. In order to contribute to this problem, the forest policy is divided into three fields and experiences are discussed.

  • Handa, E-mail: rh@mm.unknown (email)
article id 5291, category Article
David J. Brooks. (1986). Evaluating the regional and distributional impacts of forestry cost-share payments. Silva Fennica vol. 20 no. 4 article id 5291.
Keywords: forest policy; timber supply; timber market; United States; welfare economics; market simulation; cost-share payments
Abstract | View details | Full text in PDF | Author Info

Standard methods of welfare economics are used in a market simulating framework to evaluate policy measures designed to increase future timber supplies. Forest management cost-share programs are examined using this methodology. The differential regional impact of cost-share payments is considered, as is the distribution of these benefits between stumpage producers (owners of forest land) and stumpage consumers (producers of forest products). Previous estimates of the welfare gains that would result from a higher level of forest management cost-share payments in the southern United States are revised to account for the loss of public revenue resulting from lower future prices. A methodology for comparing alternative policy instruments is discussed, and a preliminary, qualitative comparison is made between the use of cost-share payments and alternative policy measures.

  • Brooks, E-mail: db@mm.unknown (email)
article id 5290, category Article
Veli-Pekka Järveläinen. (1986). Effects of forestry extension on the use of allowable cut in non-industrial private forests.