Articles containing the keyword 'trees'

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

• Sievänen, E-mail: rs@mm.unknown
• Nikinmaa, E-mail: en@mm.unknown
• Perttunen, E-mail: jp@mm.unknown

After a presentation of basic biodiversity concepts, reviews are made of studies reporting genetic implications of tree improvement activities: seed treatments, seedling production, provenance transfers, plus tree selection, seed production in seed orchards and progeny testing.

Several of the activities may influence the genetic structure and diversity of the planted forests. The general conclusion is, however, that planted forests are at least as genetically diverse as the natural stands that they replace. The diversity in forest management and use is best assurance for the future adaptability of the forests.

• Skrøppa, E-mail: ts@mm.unknown

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
• Härkönen, E-mail: sh@mm.unknown

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

The PDF includes an abstract in Finnish.

• Kuuluvainen, E-mail: tk@mm.unknown
• Pukkala, E-mail: tp@mm.unknown

The paper describes some examples from Paris and Helsinki areas, where trees are essential landscape elements. It is typical in France to plant trees around town squares, market places and along streets and roads. In Finland trees are almost always kept close to the house, together with other vegetation protecting the entrance and windows. These traditional uses of trees should be studied to serve landscape management.

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 Finnish.

• Guignard, E-mail: mg@mm.unknown

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

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

The PDF includes an abstract in Finnish.

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

Natural forest tree populations are adapted to their natural environment. Forest tree species under northern conditions are at the edge of their range where the short growing season and the low winter temperatures are the two main factors limiting their ecological niche. Effects of air pollution on the ecological niche, designated as the environmental conditions that permit a population to survive permanently, are discussed according to G.E. Hutchinson’s concept of the ecological niche. Air pollution as an additional stress factor influences the ecological niche either by the direct influence as an additional dimension of the ecological niche or by interaction with the other dimensions. These interactions are especially important for low level long-term effects of air pollution which can result in reduced resistance to low winter temperature or, due to reduced net assimilation, reduced capability to survive the long period of winter dormancy. These effects influence the boundary of the ecological niche and reduce the area of the biotope of the respective species.

Within the remaining biotope genetic changes in forest tree species take place. Due to individual differences in exposure and susceptibility of trees to air pollution, higher and therefore more exposed trees as well as more susceptible trees will be reduced in reproduction or even be eliminated. This causes genetic changes in the tree population.

• Scholz, E-mail: fs@mm.unknown

In the first part of the study the hindrance of the remaining trees when felling trees by machines working from the strip road in selective thinning was studied on the basis of the literature. In the second part there was geometrically studied the need of schematic thinning in some type stands when bundles are pre-skidded straight-lined to the strip road. In average only 0-1 trees per pre-skidding trail needs to be removed. It was concluded that trees removed from the pre-skidding trail do not significantly increase the need of schematic thinning. Remaining trees do not limit the length of machine booms if the pre-skidding trails are planned during the felling.

The PDF includes a summary in English.

• Harstela, E-mail: ph@mm.unknown

The effect of nitrogen fertilizers on the photosynthetic capacity of conifers is assessed on the basis of literature. The review emphasizes the role of changes of needle mass as a factor affecting the result of nutrient application. In particular, the increase in needle mass results in a considerable increase in photosynthetic capacity. The effect of fertilization on the photosynthetic rate seems to be of minor importance. The effect on the photosynthetic rate is, however, poorly documented as is the case for the effect of fertilization on the respiration rate. There is evidence that proper application of nitrogen fertilizers may double the photosynthetic capacity of conifers, mainly as a result of increase in needle mass.

The PDF includes a summary in English.

• Kellomäki, E-mail: sk@mm.unknown

In this article, information about tree growth which was familiar to the learned men in the old days is presented. The time when different tree species start growing, the different growth rate of various tree species, the age of trees, their resistance to injury etc. are discussed.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

A growing stand of Norway spruce (Picea abies (L.) H. Karst.) marked for cutting was investigated in the winter of 1971–72 in Helsinki in Southern Finland in order to determine the economic loss caused by decay. Taking a sample from growing spruce trees with increment borer is not a reliable method of determining the frequency of decay. The decayed stems were twice measured for assortment cutting into lengths; the first time disregarding the decay and the second time doing the actual assortment cutting according to the grade of timber. The direct economic loss caused by decay was 13% of the price for standing timber. The indirect loss may be as great as the direct loss.

The PDF includes a summary in English.

• Kallio, E-mail: tk@mm.unknown

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

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

The PDF includes a summary in English.

• Palmberg, E-mail: cp@mm.unknown

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

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

The article includes a summary in German.

• Kolehmainen, E-mail: vk@mm.unknown

The aim of the study was to update knowledge of natural range of English oak (Quercus robur L.), European ash (Fraxinus exelsior L.), Norway maple (Acer platanoides L.), small-leaved lime (Tilia cordata Miller), wych elm (Ulmus glabra Mill.) and European white elm (Ulmus laevis Pall.) in Finland, and estimate how far north they could be grown as forest trees or as park trees. The study is based on literature and questionnaires sent to cities and towns, District Forestry Boards, districts of Forest Service, Forestry Management Associations and railway stations.

The northern borders in the natural range of the species succeed one another from south to north as follows: English oak, European ash, Norway maple, wych elm, and small-leaved lime. Occurrence of European white elm is sporadic. The English oak forms forests in the southernmost Finland, while the other species grow only as small stands, groups or solitary trees. According to experiences of planted stands or trees, the northern limits of the species succeed one another from south to north as follows: European ash, English oak, Norway maple, European white elm, wych elm and small-leaved lime. All the species are grown in parks fairly generally up to the district of Kuopio-Vaasa (63 °). The northern limits where the species can be grown as park trees reach considerably further north in the western part of the country than in the east.

The article includes a summary in English.

• Ollinmaa, E-mail: po@mm.unknown

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

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

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

The PDF includes a summary in English.

• Huuri, E-mail: oh@mm.unknown

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

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

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

The PDF includes a summary in English.

• Yli-Vakkuri, E-mail: py@mm.unknown

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

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

The PDF includes a summary in English.

• Yli-Vakkuri, E-mail: py@mm.unknown

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

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

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

The PDF includes a summary in German.

• Kalela, E-mail: ek@mm.unknown

In acquiring land for the population displaced by the Second World War, the forest had to be priced, according to the Land Reclamation Act of 1945, separately for land and timber. Technical defects in the growing stock were to be taken account in the form of a total reduction in the value of the stock. Generally, it was to be 5-15% of the total value. The present investigation aims at checking the reduction percentages.

When the reduction in the felling value of the growing stock caused by the defects is estimated, the reduction is defined for each timber assortment, and the total reduction is calculated from these values. The timber assortments have big variation in prices, therefore defects in the most valuable assortments can have big effect on the total value of the growing stock. According to the study, the decree implementing the Land Reclamation Act did not in some cases allow for price reductions for defects on a sufficiently small scale to correspond to real conditions.

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

• Salo, E-mail: es@mm.unknown

The study is based on observations in a Scots pine (Pinus sylvestris L.) stand on a dry upland forest site in Karhumäki, where a 10-15-year old seedling stand grew under a hold-overs of larger trees that had been left in the site in a previous felling. The root systems of 80-120 cm tall seedlings growing around single mother trees were unearthed. Root maps were drawn of the root systems of 120 seedlings.

No seedlings grew around old, large hold-overs. It seems that seedlings could not compete with their root system. If the hold-overs were stunted in their growth, seedlings grew also under the canopy of the mother tree. 90% of the seedlings had a tap root. Rest of the roots grew horisontally in the topsoil. Around a vigorous mother tree, the seedlings grew their roots away from the mother tree. Hold-overs that had belonged originally to the lower canopy layer of the old forest did not have similar effect on the root orientation of the seedlings. Their roots had been previously affected by trees of higher canopy layer, later removed in the felling.

The PDF includes a summary in German.

• Kalela, E-mail: ek@mm.unknown

The dependence of elastic and tensile properties of coniferous trees on the share of summer wood can be presented as linear functions, if the soft wood is considered as a statically indefinite structure. By eliminating the share of summer wood by a certain function presented in the article, the elastic and tensile properties are the linear functions of density.

The functions are proved right by conducting strength tests on pine. Practical implications of the derived functions in rating the quality of wood are also presented.

The PDF contains a summary in Finnish. 

• Ylinen, E-mail: ay@mm.unknown

The study area is state owned forest of Vesijako in southern middle Finland that has earlier been intensively managed with slash-and-burn agriculture. Reforestation of broad-leaved forests into coniferous forest with controlled burning has been studied on 76 sample plots.

The article describes the practice of leasing forest stands to leaseholders who executed the controlled burning and forest regeneration and management according a leasing contract. The results of the reforestation with coniferous trees shows that sowed pine (Pinus silvestris) stands give good results but spruce (Picea abies) must be planted as a seedling.  For the state this method of forest improvement is cost effective  and should be used more widely. 

• Vuori, E-mail: ev@mm.unknown

The effective heating values of the above and below ground biomass components of mature Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.), downy birch (Betula pubescens Ehrh), silver birch (B. pendula Roth), grey alder (Alnus incana (L.) Moench), black alder (A. glutinosa (L.) Gaertn.) and aspen (Populus tremula L.) were studied. Each sample tree was divided into wood, bark and foliage components. Bomb calorimetry was used to determine the calorimetric heating values.

The species is a significant factor in the heating value of individual tree components. The heating value of the wood proper is highest in conifers. Broadleaved species have a higher heating value of bark than conifers. The species factor diminishes when the weighted heating value of crown, whole stems or stump-root-system are considered. The crown material has a higher heating value per unit weight in comparison with fuelwood from small-sized stems or whole trees. The additional advantages of coniferous crown material are that it is non-industrial biomass resource and is readily available. The variability of both the chemical composition and the heating value is small in any given tree component of any species. However, lignin, carbohydrate and extractive content were found to vary from one part of the tree to another and to correlate with the heating value

• Nurmi, E-mail: jn@mm.unknown

The heating values of wood, inner and outer bark, and foliage components of seven small-size tree species (Pinus sylvestris L., Picea abies (L.) H. Karst., Betula pubescens Erhr., B. pendula Roth, Alnus incana (L.) Moench, A. glutinosa (L.) Gaertn., Populus tremula L.) were studied. Significant differences were found between species within each component. However, the differences between species for weighted stem, crown and whole-tree biomass are very small. The weighted heating value of the crown mass is slightly higher than that of the stem in all species. The heating value of stem, crown and whole-tree material was found to increase with increasing latitude.

The effective heating value of wood correlated best with the lignin content, inner bark with carbohydrate, and outer bark with carbohydrates and the extractives soluble in alkalic solvents. It is suggested that the determination of the heating value might be used as an indicator of the cellulose content of coniferous wood.

The PDF includes a summary in Finnish.

• Nurmi, E-mail: jn@mm.unknown

The utilization of available food resources by the moose (Alces alces L.) was studied in a Scots pine (Pinus sylvestris L.) plantation containing an admixture of deciduous species. Rowan (Sorbus aucuparia L.) and aspen (Populus tremula L.) were highly utilized compared to pine and both silver birch (Betula pendula Roth) and downy birch (B. pubescens Ehrh.). However, they were not capable of withstanding continuous browsing by moose owing to their diminished biomass. In total, the browsing intensity (number of browsed twigs/tree) on pine and birch was about double of that on rowan and aspen.

The number of browsed twigs per tree increased as the amount of available main branches increased. The number of bites per available branch, as well as the maximum diameter of the bites, decreased as the density of the plantation increased. Silver birch was more used by moose than pubescent birch as well as planted silver birch compared with naturally regenerated trees.

Main stem breakage was especially common in winter 1988, the average height of the pine and birch trees being over two meters. The tops of broken stems were commonly utilized as food. The increase in moose density and the relatively deep snow cover evidently promoted the incidence of serious damage. The number of undamaged trees/ha was greater in dense than in sparse parts of the stand.

The PDF includes a summary in Finnish.

• Heikkilä, E-mail: rh@mm.unknown

Analysis of sample tree data showed that the major part of the residual variation of the stem volume estimates occurs within the forest stands. The division of the residual variation into the variation within and between populations is the basis for the mean-square error formulae of the volume estimators. Efficiency of different sample tree measurement combinations has been studied by comparing the errors of the volume estimates to the sampling costs. The measurement of the upper diameter (d6) is of less value than is generally suggested.

The PDF includes a summary in Finnish.

• Kilkki, E-mail: pk@mm.unknown

Studies on Finnish Scots pine (Pinus sylvestris L.) plus tree clones by monoterpene and isozyme analyses was undertaken to further investigate mating system, population structure and pollination. Six allozyme systems (3 GOT, 1 GDH and 2 LAP) were properly analysed on the basis of segregation. Monoterpenes were analysed from needle material and segregation in high and low 3-carene content was found to depend on two alleles C and c. Thus, six allozyme systems and one monoterpene system were used as markers in this study.

It was shown that the northern clonal group maintains a much genetic variation as the central or southern clonal groups. The conditional probability of self-fertilization in about 20-year old clones estimated by the multilocus model was 14.1%, of which 8% originate from mating between trees that carry the same alleles to one of the maternal parent at some loci and 6% through self-fertilization.

There was no prominent difference in allele frequency of male gametes that pollinated the very early or very late flowering clones. The northern clonal group has higher a lower frequency of alleles GOT B2 and B3 respectively than of the southern clonal groups. The artificial plus tree selection, particularly in northern Finland, appears to favour heterozygous genotypes for the alleles that control 3-carene content n Scots pine.

The PDF includes a summary in Finnish.

• Chung, E-mail: mc@mm.unknown

In this paper a precise definition is given of the term physiological clock and the role of this clock in biological developmental and growth processes is mathematically studied. The heat sum method employed in the study of the annual cycle of development of forest trees has been used as the starting point. The mathematical principles of this method are analysed and it is shown that, on the same principles, a fairly general physiological clock can be constructed. Also, two growth models are presented in which this generalized physiological clock proves to play an important role.

The PDF includes a summary in Finnish.

• Sarvas, E-mail: js@mm.unknown

In 1972, all Norway spruce (Picea abies (L.) H. Karst.) trees of a minimum 7 cm diameter at breast height growing in the sample plots of the Sixth National Forest Inventory were examined on the main island of Aland, Finland. The soundness of standing trees was estimated by means of external characteristics and increment borer chips. The trees were then felled and measured. They were cut into lengths, and the type and extent of decay were studied.

30% of the trees examined was affected by butt rot, ca. 3% by wound decay. A comparison of the results with those of the Sixth National Forest Inventory justifies the estimate that in Aland 23% of spruce trees exceeding 7 cm in diameter at 1.3 m had butt rot.

The proportion of decayed trees in the cubic volume was 31%. Decayed wood material accounted for 5% of the volume including bark. Butt rot increased towards the mature stands. The reduction in the number of timber trees due to decay was 14.5%, in their volume 21.5%, and in the volume of sulphite pulpwood 12%. The share of sulphate pulpwood increased from 1 to 10%. The total reduction in usable wood was 6.3%. The stumpage price of the trees fell by 10.3%. As the degree of decay increased the increment percentage of the trees decreased. The most common cause of butt rot was Fomes annosus (Heterobasidion annosum) found in 46% of the number of decayed trees. Armillaria mellea was found in 16%. Bacteria were found in 50% of the decayed trees.

The PDF includes a summary in Finnish.

• Kallio, E-mail: tk@mm.unknown
• Tamminen, E-mail: pt@mm.unknown

• López, Inland Norway University of Applied Sciences, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, P.O. Box 2400, Koppang, Norway https://orcid.org/0009-0006-6860-3408 E-mail: lucas.lopez@inn.no
• Sjølie, Inland Norway University of Applied Sciences, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, P.O. Box 2400, Koppang, Norway https://orcid.org/0000-0001-8099-3521 E-mail: hanne.sjolie@inn.no
• Nabhani, Inland Norway University of Applied Sciences, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, P.O. Box 2400, Koppang, Norway E-mail: abbas.nabhani@inn.no
• Aguilar, Swedish University of Agricultural Sciences, Department of Forest Economics, SE-901 83 Umeå, Sweden E-mail: francisco.aguilar@slu.se

We developed tree level biomass (dry weight) models for Norway spruce (Picea abies [L.] H. Karst.), silver birch (Betula pendula Roth), rowan (Sorbus aucuparia L.) and aspen (Populus tremula L.) growing in young spruce dominated seedling stands with high mixture of broadleaves. The study material was collected from three planted Norway spruce seedling stands located on mineral soil in southern Finland. Biomass models were estimated by individual tree component (stem, living branches, foliage, stump, and roots with diameter of 2 mm) by using a multi-response approach (seemingly unrelated regression), which estimated the parameters of the sub-models (tree component) simultaneously. Even though the application and generalization of the developed models can be restricted by the limited material, they provide new information of seedling biomass allocation and more reliable biomass predictions for spruce and birch growing in young seedling stand compared with those of the commonly applied biomass models (Repola 2008, 2009) in Finland. Repola’s models (2008, 2009) tended to produce biased predictions for crown and below-ground biomasses of seedlings by allocating too much biomass to roots and too little to needle and branches. In addition, this study provides biomass models for aspen and rowan, which were not previously available.

• Repola, Natural Resources Institute Finland (Luke), Ounasjoentie 6, FI-96200 Rovaniemi, Finland https://orcid.org/0000-0001-7086-0549 E-mail: jaakko.repola@luke.fi
• Luoranen, Natural Resources Institute Finland (Luke), Juntintie 154, FI-77600 Suonenjoki, Finland https://orcid.org/0000-0002-6970-2030 E-mail: jaana.luoranen@luke.fi
• Huuskonen, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0001-8630-3982 E-mail: saija.huuskonen@luke.fi
• Peltoniemi, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0003-2028-6969 E-mail: mikko.peltoniemi@luke.fi
• Väänänen, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: paivi.vaananen@luke.fi
• Uotila, Natural Resources Institute Finland (Luke), Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: karri.uotila@luke.fi

The overall increase of ungulate populations in modern Europe has contributed to conflicts in national economies, particularly between game management and the forestry sector. This study assessed damage risks to young pine (Pinus sylvestris L.), spruce (Picea abies (L.) H. Karst.) and aspen (Populus tremula L.) stands at two spatial scales. One level assessed the interaction between sex-age structure of cervid populations, measured by pellet group density, and forest damages, measured as the percentage of heavily browsed trees in 2040 stand surveys distributed proportionally throughout the country. The second level compared pellet counts and trail-camera-based records of moose (Alces alces L.) and red deer (Cervus elaphus L.) presence in a pilot study area. We examined whether 1) there is a correlation between damage amount and ungulate population structure and 2) are the data from trail cameras suitable for wider use in monitoring ungulate population structure. The study confirmed significantly higher moose pellet group densities in pine than in spruce and aspen stands. Pine damages were greater in stands with higher moose pellet group density, especially with female moose prevailing over male moose density index. The red deer pellet group densities were significantly higher in heavily damaged pine and spruce stands, regardless of sex-age structure. In most cases, there were no statistically significant differences between the two survey methods of ungulate population structure by using pellet count transects and trail camera fixations. Both methods provide comparable data on sex-age structure in moose and red deer populations if seasonal and habitat-predicted biases are considered. However, trail cameras are more widely applicable and easier to use by hunters than pellet counts.

• Done, Latvian State Forest Research Institute ‘Silava’, Riga street 111, Salaspils, LV-2169, Latvia https://orcid.org/0000-0002-2122-7154 E-mail: gundega.done@silava.lv
• Ozoliņš, Latvian State Forest Research Institute ‘Silava’, Riga street 111, Salaspils, LV-2169, Latvia https://orcid.org/0000-0002-6647-9128 E-mail: janis.ozolins@silava.lv
• Bagrade, Latvian State Forest Research Institute ‘Silava’, Riga street 111, Salaspils, LV-2169, Latvia https://orcid.org/0000-0002-1031-0665 E-mail: guna.bagrade@gmail.com
• Jansons, Latvian State Forest Research Institute ‘Silava’, Riga street 111, Salaspils, LV-2169, Latvia E-mail: jurgis.jansons@silava.lv
• Baumanis, Latvian State Forest Research Institute ‘Silava’, Riga street 111, Salaspils, LV-2169, Latvia E-mail: jbaumanis@inbox.lv
• Vecvanags, Institute for Environmental Solutions ‘Lidlauks’, Cēsis, LV-4126, Latvia https://orcid.org/0000-0003-1233-764X E-mail: alekss.vecvanags@vri.lv
• Jakovels, Institute for Environmental Solutions ‘Lidlauks’, Cēsis, LV-4126, Latvia https://orcid.org/0000-0002-2969-5972 E-mail: dainis.jakovels@vri.lv

• Nirhamo, School of Forest Sciences, University of Eastern Finland, Joensuu, Finland https://orcid.org/0000-0002-1487-533X E-mail: aleksi.nirhamo@uef.fi
• Pykälä, Finnish Environment Institute, Helsinki, Finland https://orcid.org/0000-0002-7566-9310 E-mail: juha.pykala@syke.fi
• Jääskeläinen, Kuopio Museum of Natural History, Kuopio, Finland E-mail: jaaskimmo@gmail.com
• Kouki, School of Forest Sciences, University of Eastern Finland, Joensuu, Finland https://orcid.org/0000-0003-2624-8592 E-mail: jari.kouki@uef.fi

Currently, tools to predict the aboveground and belowground biomass (AGB and BGB) of woody species in Guinean savannas (and the data to calibrate them) are still lacking. Multispecies allometric equations calibrated from direct measurements can provide accurate estimates of plant biomass in local ecosystems and can be used to extrapolate local estimates of carbon stocks to the biome scale. We developed multispecies models to estimate AGB and BGB of trees and multi-stemmed shrubs in a Guinean savanna of Côte d’Ivoire. The five dominant species of the area were included in the study. We sampled a total of 100 trees and 90 shrubs destructively by harvesting their biometric data (basal stem diameter D_b, total stem height H, stump area S_S, as well as total number of stems n for shrubs), and then measured their dry AGB and BGB. We fitted log-log linear models to predict AGB and BGB from the biometric measurements. The most relevant model for predicting AGB in trees was fitted as follows: AGB = 0.0471 (ρD_b²H)^0.915 (with AGB in kg and ρD_b²H in g cm^–1 m). This model had a bias of 19%, while a reference model for comparison (fitted from tree measurements in a similar savanna ecosystem, Ifo et al. 2018) overestimated the AGB of trees of our test savannas by 132%. The BGB of trees was also better predicted from ρDb2H as follows: BGB = 0.0125 (ρD_b²H)^0.6899 (BGB in kg and ρD_b²H in g cm^–1 m), with 6% bias, while the reference model had about 3% bias. In shrubs, AGB and BGB were better predicted from ρD_b²H together with the total number of stems (n). The best fitted allometric equation for predicting AGB in shrubs was as follows: AGB = 0.0191 (ρD_b²H)^0.6227 n^0.9271. This model had about 1.5% bias, while the reference model overestimated the AGB of shrubs of Lamto savannas by about 79%. The equation for predicting BGB of shrubs is: BGB = 0.0228 (ρD_b²H)^0.7205 n^0.992 that overestimated the BGB of the shrubs of Lamto savannas with about 3% bias, while the reference model underestimated the BGB by about 14%. The reference model misses an important feature of fire-prone savannas, namely the strong imbalance of the BGB/AGB ratio between trees and multi-stemmed shrubs, which our models predict. The allometric equations we developed here are therefore relevant for C stocks inventories in trees and shrubs communities of Guinean savannas.

• Kouamé, UFR Sciences de la Nature, UFR-SN/ Station d’Ecologie de Lamto (CRE), Pôle de recherche Environnement et Développement Durable, Université NANGUI ABROGOUA, 02 BP 801 Abidjan 02, Côte d’Ivoire); Institute of Ecology and Environmental Sciences IEES-Paris (Sorbonne Université, CNRS, Université Paris Diderot, IRD, UPEC, INRA), 4 Place Jussieu, 75005, Paris, France https://orcid.org/0000-0002-0847-2569 E-mail: kouameyag@gmail.com
• Millan, Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, South Africa; Global Change Biology Group, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa; Institute of Botany of the Czech Academy of Sciences, v.v.i, Dukelská 135, Třeboň, 379 01, Czech Republic https://orcid.org/0000-0002-0151-6055 E-mail: mathieu.millan@gmail.com
• N'Dri, UFR Sciences de la Nature, UFR-SN/ Station d’Ecologie de Lamto (CRE), Pôle de recherche Environnement et Développement Durable, Université NANGUI ABROGOUA, 02 BP 801 Abidjan 02, Côte d’Ivoire https://orcid.org/0000-0002-6333-6279 E-mail: brigitte.aya@gmail.com
• Charles-Dominique, Institute of Ecology and Environmental Sciences IEES-Paris (Sorbonne Université, CNRS, Université Paris Diderot, IRD, UPEC, INRA), 4 Place Jussieu, 75005, Paris, France https://orcid.org/0000-0002-5767-0406 E-mail: tristan.charles-dominique@sorbonne-universite.fr
• Konan, UFR Sciences de la Nature, UFR-SN/ Station d’Ecologie de Lamto (CRE), Pôle de recherche Environnement et Développement Durable, Université NANGUI ABROGOUA, 02 BP 801 Abidjan 02, Côte d’Ivoire E-mail: marcelkonan.lamto@gmail.com
• Bakayoko, UFR Sciences de la Nature, UFR-SN/ Station d’Ecologie de Lamto (CRE), Pôle de recherche Environnement et Développement Durable, Université NANGUI ABROGOUA, 02 BP 801 Abidjan 02, Côte d’Ivoire E-mail: bakadamaci@yahoo.fr
• Gignoux, Institute of Ecology and Environmental Sciences IEES-Paris (Sorbonne Université, CNRS, Université Paris Diderot, IRD, UPEC, INRA), 4 Place Jussieu, 75005, Paris, France https://orcid.org/0000-0003-3853-9282 E-mail: jacques.gignoux@upmc.fr

Current remote sensing methods can provide detailed tree species classification in boreal forests. However, classification studies have so far focused on the dominant tree species, with few studies on less frequent but ecologically important species. We aimed to separate European aspen (Populus tremula L.), a biodiversity-supporting tree species, from the more common species in European boreal forests (Pinus sylvestris L., Picea abies [L.] Karst., Betula spp.). Using multispectral drone images collected on five dates throughout one thermal growing season (May–September), we tested the optimal season for the acquisition of mono-temporal data. These images were collected from a mature, unmanaged forest. After conversion into photogrammetric point clouds, we segmented crowns manually and automatically and classified the species by linear discriminant analysis. The highest overall classification accuracy (95%) for the four species as well as the highest classification accuracy for aspen specifically (user’s accuracy of 97% and a producer’s accuracy of 96%) were obtained at the beginning of the thermal growing season (13 May) by manual segmentation. On 13 May, aspen had no leaves yet, unlike birches. In contrast, the lowest classification accuracy was achieved on 27 September during the autumn senescence period. This is potentially caused by high intraspecific variation in aspen autumn coloration but may also be related to our date of acquisition. Our findings indicate that multispectral drone images collected in spring can be used to locate and classify less frequent tree species highly accurately. The temporal variation in leaf and canopy appearance can alter the detection accuracy considerably.

• Hardenbol, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0002-0615-505X E-mail: alwin.hardenbol@uef.fi
• Kuzmin, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland; University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: anton.kuzmin@uef.fi
• Korhonen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: lauri.korhonen@uef.fi
• Korpelainen, University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: pasi.korpelainen@uef.fi
• Kumpula, University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: timo.kumpula@uef.fi
• Maltamo, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: matti.maltamo@uef.fi
• Kouki, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: jari.kouki@uef.fi

Silver birch (Betula pendula Roth) is classified in diffuse-porous wood category. In this case structure of wood tissue is quite similar across whole cross-sectional area. The aim of this study was to analyse cross-section variability of moisture content (MC) of growing silver birch wood, significant hardwood species in Polish forests. Investigations were performed on 120 model trees. In the trunk of each model tree, an increment core was collected at breast height. Samples were collected of 30 different trees in four different seasons. The greatest MC was observed during winter, lowest MC in summer. Differences in MC were statistically significant only between winter versus spring, summer, and autumn. Distribution of MC on cross-section was similar in each season. The greatest average value was observed close to pith, then it was decreasing in bark direction. The greatest difference between observed in spring – 19.51% (p < 0.05) and lowest in autumn – 4.66%. Distribution of green density (GD) on cross section was inverse proportional to MC value. Variations in GD and MC are relevant for log transport planning, weight-scaling systems, lumber drying and dynamic assessment of stiffness. Therefore, from an environmental loss perspective, it is important to determine changes in MC and GD across the year.

• Tomczak, Department of Forest Utilization, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71A, 60-625 Poznań, Poland https://orcid.org/0000-0001-5192-0294 E-mail: karol.tomczak@up.poznan.pl
• Arkadiusz, Department of Forest Utilization, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71A, 60-625 Poznań, Poland https://orcid.org/0000-0003-1140-8282 E-mail: arkadiusz.tomczak@up.poznan.pl
• Naskrent, Department of Forest Utilization, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71A, 60-625 Poznań, Poland https://orcid.org/0000-0002-0756-4162 E-mail: bartlomiej.naskrent@up.poznan.pl
• Jelonek, Department of Forest Utilization, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71A, 60-625 Poznań, Poland https://orcid.org/0000-0001-9558-9951 E-mail: tomasz.jelonek@up.poznan.pl

Expertise in the cost-efficient utilization and treatment of brushwood on forest roadside sites is limited. In the present study, the productivity of brushwood clearing and harvesting on forest roadside sites was defined by creating time-consumption models or parameters for the aforementioned working methods. Compiled time consumption models and parameters for the brushwood clearing and harvesting can be used as a basis for evaluating alternative management practices and to determine when brushwood biomass should be harvested and when it should be left to decay. The harvesting of brushwood was based on the harwarder system and the clearing of brushwood was done with a spiral cutter, which is a novel accessory for cutting roadside vegetation. Based on the study results, the average volume of harvested brushwood and forwarding distance are the key elements that have an effect on harvesting productivity with harwarders. Correspondingly, stump diameter has a strong impact on the clearing productivity of brushwood. The plot-wise productivity of the spiral cutter in brushwood clearings varied in the range of 0.19–0.61 ha per PMh. An increase in stump diameter slowed down the clearing productivity of the spiral cutter and there was a clear step downward in clearing productivity as the average diameter increased from 30 mm to 40 mm. The machinery under study operated well and there were no interruptions due to machine breakdowns.

• Laitila, Natural Resources Institute Finland (Luke), Production systems, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Väätäinen, Natural Resources Institute Finland (Luke), Production systems, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: kari.vaatainen@luke.fi

Using fine-resolution satellite imagery from multiple satellite data products, we assessed the change in forest cover of a state-managed Reserve Forest (RF) located in India’s Eastern Himalaya biodiversity hot-spot. 4.6% of forest cover was lost from Papum RF between 2013 and 2017 at the rate of 8.2 km² year^–1. Three species of hornbills: Great Hornbill Buceros bicornis Linnaeus, 1758, Wreathed Hornbill Rhyticeros undulatus (Shaw, 1811) and Oriental Pied Hornbill Anthracoceros albirostris (Shaw, 1808), that are functionally important are found here with nesting habitat in the areas affected by illegal logging. Therefore, we assessed the habitat loss within a 1 km radius around 29 nest trees. From 2011 to 2019, forest cover declined from 38.55 km² to 21.94 km² around these hornbill nest trees. Illegal logging is the main driver that is depleting forest cover within this important bird area. Our results highlight the ongoing threats to biologically-rich forests and the need for urgent measures to halt this loss. We suggest that this study has practical implications for the monitoring and governance of state-managed forests in Arunachal Pradesh.

• Sheth, #4 Ananda Nilaya, 4th Main Road, Siddhivinayaka Layout, Bengaluru 560097, Karnataka, India E-mail: chintz604@gmail.com
• Datta, Nature Conservation Foundation, 1311,“Amritha”, 12th Main, Vijayanagar 1st Stage, Mysore 570017, Karnataka, India E-mail: aparajita@ncf-india.org
• Parashuram, Nature Conservation Foundation, 1311,“Amritha”, 12th Main, Vijayanagar 1st Stage, Mysore 570017, Karnataka, India; Department of Geography, University of Cambridge, CB2 3EN, United Kingdom E-mail: dp608@cam.ac.uk

This work presents the findings of a study concerning variability in the basic density of silver birch (Betula pendula Roth) wood, depending on the geographical location of tree stands, the age and thickness of the trees, the forest habitat type, and interactions between some of these factors. The study was carried out on wood from trees aged approximately 30, 50 and 70 years in 12 forest districts located throughout Poland. In total 4777 wood samples, taken from 306 trees from 51 test plots, were measured. The location, the age of the trees, the thickness of the trees and the forest habitat type, as well as interactions between these factors, proved to have a significant influence on the basic density of silver birch wood. The highest mean values of the basic density of the birch wood were found in Sokołów forest district on the FBF habitat type (549 kg m^–3) and in Giżycko forest district on the FMBF habitat type (548 kg m^–3). For the entire set of examined material, the average values of the basic density of wood increase with tree age. For the examined material originating in FBF and FMBF habitats the average values of basic density showed no significant differences; however, in the cases of the forest districts of Giżycko, Łobez and Rudziniec, significant differences in the analysed property were observed.

• Lachowicz, Department of Forest Utilization, Warsaw University of Life Sciences SGGW, Nowoursynowska 159 02-787 Warsaw, Poland E-mail: hubert.lachowicz@wl.sggw.pl
• Bieniasz, Department of Forest Utilization, Warsaw University of Life Sciences SGGW, Nowoursynowska 159 02-787 Warsaw, Poland E-mail: anna.bieniasz@wl.sggw.pl
• Wojtan, Laboratory of Dendrometry and Forest Productivity, Warsaw University of Life Sciences SGGW, Nowoursynowska 159 02-787 Warsaw, Poland E-mail: rwojtan@wl.sggw.pl

Boom corridor thinning (BCT) has been proposed as a cost-effective technique for biomass thinning (BT) in young dense stands. The objective of this study was to determine how various BCT operations affect stand structure following biomass thinning and to compare the results with conventional selective thinning methods. Two series of field experiments were established; BCT 1-series: Three sites in south of Sweden (9 and 11 m in mean and dominating tree height) with five treatments, including a control, conventional selective thinning and three BCT treatments (1 m and 2 m wide corridors and selective BCT). The second BCT series: Three regions in Sweden (in the north, centre and in the south), with two stand sites in each region with different tree heights (4/9 m and 5/10 m in mean/dominating tree height). Treatments were control, pre-commercial thinning (PCT), conventional selective thinning and BCT (high and low thinning). Following the first biomass thinning, BCT regimes and selective thinning methods resulted in similar stand structures based on the number of possible future crop trees (>80 mm in diameter at breast height). However, BCT maintained a higher diversity of tree sizes as well as more stems per hectare, including deciduous species, than the selective thinning approaches. The stands after BCT should have more vertical complexity, especially when compared to pre-commercial thinning. The structural heterogeneity resulting from BCT may also increase stand biodiversity and ecosystem service values.

• Ahnlund Ulvcrona, Swedish University of Agricultural Sciences (SLU), Department of Forest Biomaterials and Technology (SBT), Skogsmarksgränd, SE-901 83 Umeå, Sweden E-mail: kristina.ulvcrona@slu.se
• Bergström, Swedish University of Agricultural Sciences (SLU), Department of Forest Biomaterials and Technology (SBT), Skogsmarksgränd, SE-901 83 Umeå, Sweden E-mail: dan.bergstrom@slu.se
• Bergsten, Swedish University of Agricultural Sciences (SLU), Department of Forest Biomaterials and Technology (SBT), Skogsmarksgränd, SE-901 83 Umeå, Sweden E-mail: urban.bergsten@slu.se

• San José, Instituto de Investigaciones Agrobiológicas de Galicia (IIAG), CSIC, Apartado 122, 15080 Santiago de Compostela, Spain E-mail: sanjose@iiag.csic.es
• Janeiro, INLUDES, Diputación Provincial de Lugo, Ronda de la Muralla 140, 27004 Lugo, Spain E-mail: lauravj68@hotmail.com
• Corredoira, Instituto de Investigaciones Agrobiológicas de Galicia (IIAG), CSIC, Apartado 122, 15080 Santiago de Compostela, Spain E-mail: elenac@iiag.csic.es

• San José, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda de Vigo s/n, Apartado 122, 15780 Santiago de Compostela, Spain E-mail: sanjose@iiag.csic.es
• Romero, CIFP Politécnico de Santiago, Santiago de Compostela, Spain E-mail: lr@nn.es
• Janeiro, INLUDES, Diputación Provincial de Lugo, Lugo, Spain E-mail: lauravj68@hotmail.com

• Li, Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing 100083, China E-mail: gl@nn.cn
• Liu, Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing 100083, China E-mail: lyong@bjfu.edu.cn
• Zhu, Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing 100083, China E-mail: yz@nn.cn
• Li, Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Forest Silviculture of State Forestry Administration, Beijing 100091, China E-mail: qml@nn.cn
• Dumroese, US Department of Agriculture, Forest Service, Rocky Mountain Research Station, Moscow, ID, USA E-mail: rkd@nn.us

• Vandekerkhove, INBO, Gaverstraat 4, B-9500 Geraardsbergen, Belgium E-mail: kris.vandekerkhove@inbo.be
• De Keersmaeker, INBO, Gaverstraat 4, B-9500 Geraardsbergen, Belgium E-mail: ldk@nn.be
• Walleyn, INBO, Gaverstraat 4, B-9500 Geraardsbergen, Belgium E-mail: rw@nn.be
• Köhler, Koleopterologisches Forschungsbüro, Bornheim, Germany E-mail: fk@nn.de
• Crevecoeur, Genk, Belgium E-mail: lc@nn.be
• Govaere, Agency of Nature and Forests, Brussels, Belgium E-mail: lg@nn.be
• Thomaes, INBO, Gaverstraat 4, B-9500 Geraardsbergen, Belgium E-mail: at@nn.be
• Verheyen, Ghent University, Laboratory of Forestry, Gontrode, Belgium E-mail: kv@nn.be

• Laitila, The Finnish Forest Research Institute, Joensuu, Finland E-mail: juha.laitila@metla.fi
• Heikkilä, L&T Biowatti Oy, Seinäjoki, Finland E-mail: jh@nn.fi
• Anttila, The Finnish Forest Research Institute, Joensuu, Finland E-mail: pa@nn.fi

• Eriksson, SLU, Dept of Bioenergy, P.O. Box 7061, SE-750 07 Uppsala, Sweden E-mail: ee@nn.se
• Johansson, SLU, Dept of Bioenergy, P.O. Box 7061, SE-750 07 Uppsala, Sweden E-mail: tj@nn.se

• Sayyad, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: es@nn.ir
• Hosseini, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: hosseini@europe.com
• Mokhtari, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: jm@nn.ir
• Mahdavi, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: rm@nn.ir
• Jalali, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: sgj@nn.ir
• Akbarinia, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: ma@nn.ir
• Tabari, Tarbiat Modarres University, Natural Resources Faculty, Emam St. Noor, 46414 Noor, Mazandaran, Iran E-mail: mt@nn.ir

• Storaunet, Norwegian Forest Research Institute, Høgskolevegen 8, NO-1432 Ås, Norway E-mail: ken.storaunet@skogforsk.no
• Rolstad, Norwegian Forest Research Institute, Høgskolevegen 8, NO-1432 Ås, Norway E-mail: jr@nn.no
• Gjerde, Norwegian Forest Research Institute, Fanaflaten 4, NO-5244 Fana, Norway E-mail: ig@nn.no
• Gundersen, Norwegian Forest Research Institute, Fanaflaten 4, NO-5244 Fana, Norway E-mail: vsg@nn.no

• Ericsson, SLU, Dept. of Forest Vegetation Ecology, S-901 83 Umeå, Sweden E-mail: staffan@delta.se
• Östlund, SLU, Dept. of Forest Vegetation Ecology, S-901 83 Umeå, Sweden E-mail: lo@nn.se
• Andersson, SLU, Dept. of Forest Vegetation Ecology, S-901 83 Umeå, Sweden E-mail: ra@nn.se

• Linder, Department of Forest Vegetation Ecology, SLU, S-901 83 Umeå, Sweden E-mail: pl@nn.se
• Jonsson, Department of Forest Vegetation Ecology, SLU, S-901 83 Umeå, Sweden E-mail: pj@nn.se
• Niklasson, Southern Swedish Forest Research Centre, SLU, Box 49, S-230 53 Alnarp, Sweden E-mail: mn@nn.se

• Givnish, Dept of Botany, University of Wisconsin, Madison, WI 53706, USA E-mail: givnish@facstaff.wisc.edu

• Lundqvist, Deparment of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden E-mail: lars.lundqvist@slu.se
• Spreer, Sveaskog Förvaltnings AB, Ljusdal, Sweden E-mail: susanne.spreer@sveaskog.se
• Karlsson, Field Research Unit, Swedish University of Agricultural Sciences, Siljansfors, Sweden E-mail: christer.karlsson@slu.se