Articles containing the keyword 'rot'

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
• Heliövaara, E-mail: kh@mm.unknown
• Peltonen, E-mail: mp@mm.unknown
• Saarenmaa, E-mail: hs@mm.unknown

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
• Kotiranta, E-mail: hk@mm.unknown

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
• Jeanrenaud, E-mail: jj@mm.unknown
• Markham, E-mail: am@mm.unknown

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

The aim of the study was to compare the behaviour of three selected provenances of Eucalyptus microtheca F. Muell. that were likely to respond differently to drought. For this purpose, we studied the effects of vapour pressure deficit and soil water content on leaf water potential in an irrigated plantation in Bura, eastern Kenya.

An international provenance trial of Eucalyptus microtheca, established as a part of Finnida-supported Bura Forestry Research Project in eastern Kenya in 1984 was used as a plant material in the study. The eastern provenance showed generally the lowest leaf water potential on a daily basis. Statistically significant differences in the daily leaf water potential fluctuations were detected. The eastern provenance exhibited the greatest and the northern one the smallest values. The minimum daily leaf water potential of the provenances responded well to changes in gravimetric soil water content, the western provenance being the most sensitive one. The relationship of the observed results and annual rainfall distribution in the geographic regions of the studied provenances is discussed.

• Tuomela, E-mail: kt@mm.unknown
• Kanninen, E-mail: mk@mm.unknown

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
• Rossi, E-mail: pr@mm.unknown
• Saarsalmi, E-mail: as@mm.unknown

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

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

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

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
• Saarsalmi, E-mail: as@mm.unknown

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

The PDF includes an abstract in Finnish.

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

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

The PDF includes an abstract in Finnish.

• Lähdesmäki, E-mail: pl@mm.unknown
• Pietiläinen, E-mail: pp@mm.unknown

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
• Törmälä, E-mail: tt@mm.unknown

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
• Seppälä, E-mail: ms@mm.unknown

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

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
• Ellefson, E-mail: pe@mm.unknown

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

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

The PDF includes a summary in Finnish.

• Löyttyniemi, E-mail: kl@mm.unknown
• Uusvaara, E-mail: ou@mm.unknown

A total of 146 Norway spruce-dominated clear-cutting areas and 140 of the sample plots included in the 7th National Forest Inventory in Finland were examined during 1974–78. The micro-organisms causing decay in Norway spruce (Picea abies (L.) H. Karst.) sample trees were identified. The most common causal agent of butt-rot was Heterbasidion annosum (Fr.) Bref. Other fungi causing decay in the spruce trees were Armillaria mellea (Vahl.) Quél, Stereum sanguinolentum (Alb. & Schw. ex Fr.), Resinicum bicolor (Alb. & Schw. ex Fr.) Parm. and Climacocystis borealis (Fr.) Kotl. & Pouz. Species of Ascocoryne were very often present in the decay. The decay caused by H. annosum was considerably more extensive than cases of decay where the fungus was not present.

The PDF includes a summary in Finnish.

• Hallaksela, E-mail: ah@mm.unknown

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

The PDF includes a summary in Finnish.

• Rousi, E-mail: mr@mm.unknown

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

The PDF includes a summary in Finnish.

• Löyttyniemi, E-mail: kl@mm.unknown

The present study deals with the effect of forest drainage on some quality factors of brook waters. Under study were several brooks in the basin of the Kiiminkijoki River as well as its main tributary, the Nuorittajoki River. These are located in Northern Finland and belong to the international water program Project Aqua.

The following values were determined for the water samples: pH, electric conductivity, colour, concentration of suspended solids., NO₂, NO₃, and NH₄ nitrogen concentrations, dissolved and total phosphorus, and Ca, Mg, K and Fe concentrations. Water quality in the brooks was monitored prior to and after ditching. A statistically significant change was noted in colour, in the concentration of suspended solids, in the NH₄ concentration and in some brooks also in the pH value and in the total phosphorus, K, and Fe concentrations.

The PDF includes a summary in English.

• Hynninen, E-mail: ph@mm.unknown
• Sepponen, E-mail: ps@mm.unknown

The paper evaluates the effect of the change in the forest taxation laws which came into force in January 1977 on the value of the taxable cubic metre in each commune, a measure of the mean timber price. The taxable cubic metre is taken into include timber assortments corresponding to the mean planned cut for the area, which are then assessment at their mean local stumpage prices. Account is also taken of the mean costs involved in forestry, which increase from the south of Finland to the north.

The new principles of taxation, based on data from the V and VI National Forest Inventories, give higher values for the taxable cubic metre, and thus heavier taxation, in the Southern Finland, largely by allowing for a higher proportion of saw logs than previously, and lower values, an easing of taxation, in the north.

The PDF includes a summary in English.

• Häkkilä, E-mail: mh@mm.unknown

The paper deals with the problems of the preservation of the redwood groves (Sequioia sempervirens (D. Don) Endl. and Sequoiadendron giganteum (Lindl.) J. Buchholz) in California. The activity to protect these groves from flood and fire may finally lead to dying of these long-lived trees. A program to use prescribed burning as a tool for the management of natural ecosystem has been started.

The PDF includes a summary in English.

• Nuorteva, E-mail: mn@mm.unknown

In the first place the term short-rotation forestry is being used in the sense of intensive tree growing during a short rotation time using reproduction by coppice shoots from broad-leaved tree material which has been specially bred for this purpose, or of producing fast-growing varieties from planted stock during the course of somewhat longer rotation time (maximum 20 years). However, short-rotation forestry as such has already a long history.

In the Fertile Crescent in ancient Egypt grew no tree species suitable for short-rotation production, but reeds and bulrushes were used for the same purpose as willow-twigs, e.g. wickerwork or binding. At least in the Fertile Crescent reed harvesting using a rotation of one year was practiced already very long ago. The earliest information about coppice-shoot cultivation is found in Greek literature, but it was the Romans who developed short-rotation forestry based on the trees’ capacity of reproducing through coppice shoots into an extensive economic activity. Willows were by far the most important species used. Twigs intended for wickerwork were harvested once a year and thicker material, to be used for support and in basket framework, every fourth year. Chestnut and oak were used for the production of slightly thicker poles employing a longer rotation. Cypress poles were produced from seedlings using a rotation time of 12–13 years. Roman scholars give us plenty of information concerning the tending of plantations in short-rotation forestry.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

It is possible to show that many of the after-effects resulting from the disappearance of forest cover were well known already in ancient times. The invigorating effect of moving around freely in the forest and its artistic creative ability were also recognized as well as the healing effect of coniferous forest on people suffering from consumption. Hunting and the use of forests for cattle grazing is also an extremely old practice. The so-called by-products of the forest such as tree bark and leaves, as well as berries and fruits, have played an important role in the history of mankind from the very earliest beginnings.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

The effect of spacing on the first-year yield and height increment of Alnus incana (L.) Moench, Populus tremula L. x Populus tremuloides Michx. (Populus x wettsteinii), Salix ’Aquatica Gigantea’, and Salix phylicifolia L. was studied at the Arctic Circle Agricultural Experimental Station in Northern Finland. S. ’Aquatica Gigantea’ gave yields which were twice as high as those of the other species in the study. The highest yields were of the order of 60 tons per hectare (fresh yield including foliage). The annual height growth in S. ’Aquatica Gigantea’ was about 100 cm, in the others about 30–50 cm. S. ’Aquatica Gigantea’ had a maximal height growth when the distance between the seedlings was 25 cm.

The PDF includes a summary in English.

• Pohjonen, E-mail: vp@mm.unknown

The purpose of the study was to find out whether Fomes annosus (now Heterobasidion annosum) growing in a Norway spruce (Picea abies (L.) H. Karst.) stump can, with its mycelium, take up the radioactive isotopes ³H, ³³P and ¹²⁵I in the heading, and whether it transfers them via the sporophores in situ to its basidiospores. Wood material in close proximity to active sporophores was injected with radioactive isotopes. All isotopes could be verified from the basidiospores. The production of viable basidiospores by sporophore was reduced by the isotope injections. This latter result may be of importance e.g. in meteorology for observation of the movements of air masses.

The PDF includes a summary in English.

• Kallio, E-mail: tk@mm.unknown
• Selander, E-mail: js@mm.unknown
• Uusi-Rauva, E-mail: au@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

There is no clear picture in Finland of how big the revenues are that the State and the local authorities receive from taxation for the part of primary forestry. Conception of taxation varies from 100% to 50%. The paper presents a comparison between the gross income from timber sales as determined according to the method used at the Central Statistics Bureau and the net revenues as calculated on the basis of forest fee.

At 1920s area taxation was introduced in forest taxation. The system is based on forest types and their timber production capacity. According to the principles of area taxation, no tax is paid for overcuts, whereas timber capital savings should be paid for.

According to the calculations of this study, in 1958–62 the gross income from timber sales was about 506 million Fmk annually in Southern Finland, the costs involved in timber production about 437 million Fmk, and the annual taxable income 231 million Fmk. In the period more valuable timber assortments were harvested than those for which taxes were paid according to the old regulations.

Half a century ago, area taxation was a system suited to its purpose. Now, however, forestry is in the hands of another generation, and accounting has been introduced in practical agriculture and forestry. Therefore, a taxation system based on the real income from timber growing should be introduced. The transition period could even be relatively short. It seems probable that a forest owner does not sell timber at a time when this would be required by silvicultural aspects in order to avoid income taxation, he should have to be present an acceptable working plan.

The PDF includes a summary in English.

• Lappalainen, E-mail: al@mm.unknown

The study attempts to establish to what extent the present regional allocation of the forest improvement subsidies equalize the profitability of forest drainage in Finland. The benefit/cost ratio has been used to describe the regional variation of the profitability

The study revealed that the forest improvement subsidies granted in 1968, even the highest possible subsidies, did not equalize the profitability of forest drainage. According to the results, the northern regions are at a disadvantage compared to the southern parts of the country. To fully equalize the profitability of forest drainage the average subsidies granted in 1968 should have been raised in the second financing zone from 22 to 32%, in the third zone from 32 to 60%, and in the fourth, northernmost zone from 43 to 86%. The study also suggests that the boundary lines of the financing zones should run, at least in Central and Northern Finland, from southeast to northwest instead from east to west, as it is now.

The PDF includes a summary in English.

• Numminen, E-mail: jn@mm.unknown

Fomes annosus (Fr.) Cke. (now Heterobasidion annosum (s.str.)) has proved highly adaptable to varying conditions. Thus, the fungus is able to alter the pH as well as in alkalic as acid direction according to the original pH-grade. The fungus spreads mainly by basidiospores or by the sterile mycelium, but maybe also by the conidiospores. The fungus has spread through the temperate zone; in the tropical and sub-tropical zone it is found sporadically. There is a mention in the literature of at least 136 species in which it has been found. It is found in hardwoods but is most disastrous in conifers. The economic losses are considered biggest in England, Germany and Scandinavia.

The research has not been able to find a safe way to protect the trees growing on an infected site. The only way to limit the damage seems to be the use of mixed stands. Stump-protection has proved to be a relatively effective way to prevent the spread of the fungus to uninfected sites. The formerly used creosote has been mainly substituted by new chemicals, such as sodium nitrite. They act by altering the stump in a way that is favourable for antagonists to Fomes annosus, such as Trichoderma viride and Penicillium sp., or the recently presented Peniophora gigantea.

Although the fungus is found in many tree species, there is a difference in the relative resistance of different species. Among the conifers, the Abies-species (with exception of Abies grandis, A. alba and A. sachalienensis) are considered comparatively resistant. The species of Larix and Pseudotsuga are more resistant than those of Picea and Pinus.

The PDF includes a summary in English.

• Palmberg, E-mail: cp@mm.unknown

The aim of this paper was that of studying the optimum growing schedules of forest stands, with the classic Faustmann formula as starting point. The study is mainly theoretical in nature. The study shows that the net present-value of the future revenues from a forest stand can be calculated, not only by means of the harvesting revenues, but also by a more theoretical concept, here termed the current gross soil rent. The current gross soil rent represents the difference between the current value growth and the rent of the growing stock.

By use of the concepts described here, it is theoretically possible to find the growing schedule for the stand which maximizes the net present-value of the stand. To make the formulae simpler, a one-year period has been adopted for discussion of the concepts involved in determination of the optimum structure and density of the growing stock, and the financial maturity. However, these concepts can be extended to cover periods of any length.

The method for determination of the optimum growing schedule for a forest stand can be summarized as follows: Thin the stand as the internal rate of return on the marginal increase in ’timber capital’ falls below the guiding rate of interest. Clear-cut and regenerate the stand as the internal rate of return on the sum of the ’timber and soil capital’ falls below the guiding rate of interest.

The PDF includes a summary in Finnish.

• Kilkki, E-mail: pk@mm.unknown

The Finnish Government appointed a committee in 1959 to study the drawbacks of the present system of forest taxation, and to make recommendations for their elimination. It was not within the Committee’s terms of reference to decide whether the present taxation procedure, which is based on assessment per unit of area, should be replaced entirely by another system.

The committee made several proposals to mitigate the hardships entailed in the collective nature of Finnish forest taxation. It also proposed tax relief for areas which are to be the main target of forest improvement work. Among the other recommendations of the committee, can be mentioned simplification of the taxation in Northern Finland by having only two yield classes for that region.

The PDF includes a summary in English.

• Metsäverokomitea, E-mail: –

A committee was appointed in 1940 to prepare a proposal for reform of forest taxation. The taxation based on net income of forestry was considered to have limitations, and the actual net income had been observed to be markedly higher than the income that was used in taxation.

The report describes in detail the principles and shortcomings of taxation used since 1922. These include inaccuracies in the forest areas of a woodland estate, and weaknesses in classification of forest land and demand zones. The committee suggests several improvements in calculating the taxable income, which in the new calculations is based on yield on terms of value.

The article includes an abstract in German.

• Metsäverotuksen uudistamiskomitea, E-mail: –

Silva Fennica issue 42 includes presentations held in professional development courses, arranged for foresters working in public administration in 1936. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service

This presentation describes the principles of forest taxation in Finland in 1930s.

• Ilvessalo, E-mail: yi@mm.unknown

Metsähallitus (Forest Service) decided to protect two areas around Hiisijärvi lake in Eastern Finland already in 1916. Later, a natural park was suggested to be established in the area. A survey of the vegetation in the area was composed in 1931-1932. The total land area of the protected area was 3.5 km³. A vegetation map was drawn based on a nature inventory. A detailed description of the forest site types, peatland types, aquatic flora and the vegetation of the area are included in the article. The calcareous soil promotes rich vegetation. Typical for the area are also rich fens. The area can be divided to a eutrophic and a oligotrophic part.

The PDF includes a summary in German.

• Brandt, E-mail: ab@mm.unknown

The article gives a proposal for areas that would be suitable for protected areas, situated in state-owned lands in Northern Finland. Eight areas are described in the article, namely Oulankajoki area in Northern Kuusamo, Kutsajoki area in Kuolajärvi, Pyhätunturi in Kemijärvi, Pisavaara in Rovaniemi, Pallastunturi and Ounastunturi area, Malla fells in Kilpisjärvi, Pääskyspahta area in Petsamo and Heinäsaari in Petsamo.

Each of the areas possess special features in Finnish nature, samples of which should be reserved in pristine state. Furthermore, costs of the protection are small. The resident population is, however, in general against protection. The protection should therefore be organized in a way that minimizes the disadvantages caused by limitations to land use, for example grazing, reindeer husbandry, fishing and hunting.

According to Finnish Nature Conservation Act, all wildlife in the conservation areas should be protected. Protection of wolverine and wolf is, however, difficult because of the damages they cause for domestic animals. Protection of bear is regarded to be possible in most of the proposed protected areas.

• Linkola, E-mail: kl@mm.unknown

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

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

The PDF includes a summary in English.

• Kallio, E-mail: tk@mm.unknown

The forest management practices in Finland are closely related to the industrial history in the country. The selection cutting method used previously has now been gradually disappearing, and differences in the quality of forest management can still be observed between different owner groups. The national forest inventories indicate that farm woodlots show the poorest silvicultural state among the ownership categories. This study analyses social and economic causes responsible for variation in the silvicultural state of farm woodlots managed jointly with a cultivated land holding. The study is based on the data of third national forest inventory in Finland, and a factor analysis was calculated using the data.

Although the model developed explains more than a half of the total variance of the level of silviculture, only less than third of this is clearly explained by economic and social factors. The remaining two thirds are explained by the ’nature factor’, which includes both economic and site factors. This affects the effect of different kinds of forest policy measures. Of the variables in the model, the strongest influence in the level of silviculture have income, size of woodlot, size of land area under cultivation and distribution of forest types. The differences in the level of silviculture between different woodlots and different districts, may be explained by the theory of cumulative process. Regional differences in economic phenomena cannot be explained without taking into consideration the social value hierarchy in each region, which determines the range of variation of economic variables.

The PDF includes a summary in English.

• Riihinen, E-mail: pr@mm.unknown

In this investigation was studied 1) Volume growth and yield of timber in managed Norway spruce (Picea abies (L.) Karst.) forests under different rotations. 2) Value growth, net forest income and soil expectation value of managed forests under different rotations, and 3) The rotations of spruce forests managed on different rotation principles. The data was collected from Oxalis-Myrtillus type forests in South-West Finland.

Two developmental series of stands were constructed for the research, one of which were of better sites than the other. Sample plots were pure, even-aged spruce stands in well-managed forests. The stands had been thinned from below. The age varied from 25-30 years to the age of final cutting.

According to the study, in the artificially regenerated spruce stands the highest mean annual volume growth, 9.7 m³/ha, and also the highest net annual income of 14,50 Finnish marks/ha (calculated from average stumpages) was reached in rotation of 70 years. In the other managed spruce forests a mean annual volume growth of 6.6-8.8 m³/ha and the net annual income of 10,500-14,500 Finnish marks/ha were reached in the rotation of 70-100 years. The rotation for the maximum mean annual volume growth varied in the different series between 67-92 years. The maximum mean annual forest rent was only achieved in series B in a rotation of about 100 years, and in a naturally normal stand in a rotation of about 120 years. The intensity of thinnings and silviculture had a greater effect on value growth and on net income than on volume growth.

The PDF includes a summary in English.

• Kallio, E-mail: kk@mm.unknown

Due to the nature of forest taxation in Finland, there has been no information available on the amount of tax paid by forestry or of taxable forestry income. The main reason for this is the close connection of taxation of forestry and agriculture, which has made it difficult and expensive to separate the information of the sectors. This study determined the amount of taxable forestry mathematically based on statistics on the taxable forest areas in each tax zone on a county level.

The article concludes that the stumpage has been considerably higher than the taxable income in 1950-1953. In 1951 only 18.5% of the income received as stumpage was taxed, but in 1953 the proportion was 82.8%. In average 45% of the stumpage amount had become subject to taxation.

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

The PDF includes a summary in English.

• Selin, E-mail: ls@mm.unknown

In Finland the state has to pay local government taxes and certain connected smaller taxes, such as church and land taxes and forest management fees, on its forest property. On the other hand, the state tax on income and property is not collected, as the corresponding amount goes to the state in the form of a state forestry surplus.

It has been stated that if the state should pay similar taxes as companies do, the income of state forests would be small. The author has calculated the different taxes if the state forests would be a company or an individual tax-payer. As a company the income and property taxes would amount to 1,251 million marks and as a company to 730 million mark when the year 1952 is used as a reference. In drawing up the balance sheet for state forestry, local government taxes and other similar charges have been taken into account as expenses. By comparing the surplus with the calculated state tax payable, the state forestry would give a surplus, after deduction of taxes, of 1,846 million marks as an individual and 2,367 million marks as a company. State forestry would thus have been able to pay state income and property taxes from its surplus.

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

The PDF includes a summary in Engilsh.

• Piha, E-mail: ap@mm.unknown

In Finland the state has to pay local government taxes and certain connected smaller taxes, such as church and land taxes and forest management fees, on its forest property. On the other hand, the state tax on income and property is not collected, as the corresponding amount goes to the state in the form of a state forestry surplus.

It has been stated that if the state should pay similar taxes as companies do, the income of state forests would be small. The author has calculated the different taxes as if the state forestry would be a company or an individual tax-payer. As a company the income and property taxes would amount to 1,251 million marks and as a company 730 million marks using the data of 1952. In drawing up the balance sheet for state forestry, local government taxes and other similar charges have been taken into account as expenses. By comparing the surplus with the calculated state tax payable, the state forestry would give a surplus, after deduction of taxes, of 1,846 million marks as an individual and 2,367 million marks as a company. State forestry would thus have been able to pay state income and property taxes from its surplus.

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

The PDF includes a summary in Engilsh.

• Osara, E-mail: no@mm.unknown

Many countries have enacted plant protection laws or statutes that consist timber imported into a country, both raw wood and processed timber. This has caused some inconvenience to the international timber trade. Necessary protection against the spread of pests via export is fully acceptable, but the protection should be based on actual need.
When considering processed or barked raw timber, the problem concerns only species that pass their development in the wood. The four most important biological requirements affecting the risk are 1) the tree species of the importing country and affinity of the pest, 2) climatic conditions of the importing country and the pest’s range and adaptability to the climate, 3) biological factors regulating the population, and 4) suitability of the individual development of the pest for transmission. These risks are discussed in the article.

It is concluded that it is possible largely to eliminate the species that might be conveyed via export timber. It is often possible to decide in advance what danger threatens the importing country from species that might be conveyed via export timber. This would make it possible to adapt plant protection regulations to suit the relation between the exporting and importing countries.

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

• Kangas, E-mail: ek@mm.unknown

Observatons of drying of Norway spruce (Picea abies (L.) Karst.) stands increased in 1930s in Southern Finland. The aim of the study was to analyse the advance and causes of drying. The work was begun in 1930s before the Second World War, and the damages caused to the forests by the war was used as supplemental observations in the study. A special method, drying analysis, was developed to study the process. It was used both in cases of insect and fungal diseases in the four research areas in Raivola and Ruotsinkylä. In addition, 7 observation areas were studied.

Several causes for drying of the trees were observed in the Norway spruce stands. These included European spruce bark beetle (Dendroctonus micans), root rot (Heterobasidion annosum), pine weevils (Pissodes sp.), bark beetles and honey fungus (Armillaria mellea).

The role of primary and secondary causes for drying, resistance of the trees and the drying process are discussed. Finally, the influence of forest management in drying process is analysed. Forests in natural state can be considered to be in an ideal balance. On the other hand, forest management can be used to maintain the vitality and resistance of the forests. Drying of Norway spruce stands can be taken into consideration when the stands are managed.

The PDF includes a summary in German.

• Kangas, E-mail: ek@mm.unknown

The drained peatlands regenerate usually well, and artificial regeneration by sowing or planting has been rare. Field trials of Norway spruce (Picea abies (L.) H. Karst.) were established in northern Satakunta in Western Finland in three drained peatlands in 1934. Sowing trials of Norway spruce consisted of patch and broadcast sowed sample sites in treeless bogs and under protective forest. The seedlings of spruce were planted either under protective forest or in treeless peatland.

The results show that artificial regeneration of Norway spruce succeeds best under protective forest. The best tree species for upper storey is Betula sp. which grows fast and controls growth of ground vegetation. The peat is relatively decomposed on those peatlands that are suitable for spruce, and breaking of the surface of the peat is not recommended. In the sowing trials, breaking of the upper layer of the peat caused frost heaving, cracking of the dried surface and sticking of mud in the seedlings in the patch sown sample site. The shoot and root growth of seedlings of the broadcast sown site was better than seedlings of the patch sown site. The planted spruce seedlings seemed to be more susceptible for spring frost than the seedlings in the sown site. The plants of seed origin succeeded in general better than the planted seedlings.

The PDF includes a summary in German.

• Multamäki, E-mail: sm@mm.unknown

There are two fungi that cause butt rot: Fomitopsis annosa and Bjerkandera borealis. The losses they cause in pine forests are relatively mild, the share of rotten trees is between 6 and 12 % and the rot is restricted to the butt end of the tree.

In forests dominated with spruce the losses to timber are more notable. The share of trees infected with butt rot is between 10 and 40 % and of the volume at least 12 per cent. The more barren the heath forest site the greater the defect caused by decay. In the forests on peatland the pine swamps and spruce moors are the most affected.

The PDF contains a summary in Finnish.  

• Tikka, E-mail: pt@mm.unknown

In 1926 the state of Finland payed taxes to the local municipalities from a half of the net returns the state forest and state owned wood manufacturing industry produced. The taxes payed by the forest administration to the municipalities totaled 4.75 million Finnish marks. The state forests are located mostly in Northern Finland, thus the relative amount of municipalities that get taxes from the state forestry were higher in the north. The municipalities that benefited most from the tax revenues from the state were Savukoski, Pudasjärvi, Suojärvi, Rovaniemi, Taivalkoski, Kuhmoniemi, Turtola, Pielisjärvi, Ilomantsi, Korpiselkä and Suistamo. About half of the municipalities (264) got tax revenues from state forestry. However, if this tax revenue was removed, it would raise local tax rate in relatively few municipalities. it has been proposed that state should pay taxes from the state forests on the same principles as the private forests. To move to area based taxation in the state forests would, however, increase the taxation of the state five-fold. The taxes from the state forests are not appropriate way to support the poorest municipalities. Better suited would be, for instance, state subsidies. Therefore, the taxes payed from the state forestry to municipalities should be abandoned.

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander. The PDF includes a summary in German.

• Lakari, E-mail: ol@mm.unknown

The aim of the study was to compare the theories of Soil Rental and Forest Rental. There is a controversy between the theories that is associated to the issues of length of rotation and grade of thinning. For the basis of the analysis was chosen Schwappach’s money yield table for Scots pine (Pinus sylvestris L.) Quality II, published in 1908. Based on the table was calculated the financial yield, the net annual income from a normal forest managed on various rotations, the capital value, and the net income expressed as the rate of interest on the capital value. According to the study, it is the rotation at which any money invested in lengthening the rotation still further, would yield no return. In the case of Scots pine, the highest income is achieved approximately with a rotation of 140 years, and the income per hectares would decrease if longer rotations were used, though the capital invested would increase.

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.

• Hiley, E-mail: wh@mm.unknown

The article deals with laboratory experiments of humus containing soil samples that were tested for leaching of iron and lime. The humus and soil samples were collected in five different areas in Silesian state forests, Germany.

The chemical content of the extracts was measured in the beginning of the test. The flocculation experiments and experiments in glass tubes took place. The stronger or weaker the podsolization, the greater or smaller was the protective action of hums at the respective place. However, more research is needed. The results of the glass tube experiments seem to indicate that with humus there were smaller amounts of Ca and Fe leaching than with merely water. 

• Aaltonen, E-mail: va@mm.unknown

The article is based on observations made during a decade in the parishes of Utsjoki and northern, middle and eastern parts of Inari in Finnish Lapland. At the timber line the pine regenerates very slowly. The amount and quality of pine forests on their timber line has been diminishing because of forestry, expansion of settlements and reindeer pasturing.  

Assigning the pine forests on the timber line as protection forests would serve the nature protection purposes as well as the wellbeing of the inhabitants and the state. Protection of areas where the regeneration is weak as well as the birch forests that serve as source of firewood for local people is of particular important. Measures against forest fires need to be taken. Extensive use of forests for reindeer pastures have caused a threat to existence of those forests.

When it comes to forest management, securing the seed yield and the survival of the seedlings need to be taken care. The productivity of the forests must be increased. For growing amount of people living in the area, the need for firewood and timber for other purposes must be fulfilled without increasing pressure to nearby forests.    

• Heikinheimo, E-mail: oh@mm.unknown
• Renvall, E-mail: ar@mm.unknown

The third part of the six-article series about protection forest in Northern Finland describes prevention of forest fires in the pine timber line area. The article gives a proposal for a forest fire decree. According to the proposal, lighting a campfire should be prohibited in dry and windy times. Vegetation should be cleared around a campfire in the summertime. The local people should be obliged to help to extinguish any forest fire, and given compensation for the work. The compensation would be claimed from the person who lit the fire, if that is known. A fine is collected if forest fire breaks out by negligence. 

The article is divided in six parts. The parts II and III of the article series are included in the same PDF. A German summary is in a separate PDF.

• Renvall, E-mail: ar@mm.unknown

The article aims to give a proposal on how to organize a protection forest system to protect the pine timber line in the northernmost Finland. In this first part of the six-article series is described the range and biology of Scots pine (Pinus sylvestris L.) in the timber line area, and human actions influencing the species in the area. The southward shift of Scots pine timber line cannot be explained by change of climate. The main factors are too intensive fellings, reindeer husbandry and forest fires. The poor reproduction of pine in Lapland makes it vulnerable to disturbances. The trees produce viable seeds in average only every 100 years. Thus, effective measures are needed to protect the existing pine forests in the area.

The article is divided in six parts. A German summary is in a separate PDF.

• Renvall, E-mail: ar@mm.unknown

A nonlinear programming algorithm was combined with two individual-tree growth simulators consisting of distance-independent diameter and height growth models and mortality models. Management questions that can be addressed by the optimization model include the timing, intensity and type of thinning, rotation age, and initial density. The results were calculated for Norway spruce (Picea abies (L.) H. Karst.) stands on Oxalis-Myrtillus site in Southern Finland, where the stand density after clearing of a seedling stand is about 2,000 trees/ha.

The optimum thinning programs were characterized by late first thinnings (at dominant height of 15–17 m) and relatively high growing stock levels. It was optimal to thin from above, unless mean annual increment was maximized instead of an economic objective. In most cases, the optimum number of thinnings was two or three. Compared to a no-thinning alternative, thinnings increased revenues by 15 –45% depending on the objective of stand management. Optimum rotation was strongly dependent on the interest rate.

Hooke and Jeeves’ direct search method was used for determining optimum solutions. The performance of the optimization algorithm was examined in terms of the number of functional evaluations and the equivalence of the objective function values of repeated optimizations.

The PDF includes a summary in Finnish.

• Valsta, E-mail: lv@mm.unknown

The aim of this paper was to study the nature of the relative areal differences in the Finnish forests in respect of timber yield, intensity of exploitation and stumpage prices. The yield index is the most inconsistent and the source of the greatest regional differences. The differences arise even in Southern Finland, as the yield in the South-West is only 80 % of that obtained in Eastern Häme. The areal variations in the wastage index are of the order of only 10 % at most, and the stumpage price index is relatively constant, remaining within the 10 % limit, as far north as the southern boundary of the province of Oulu.

Indices for the forest yield and final forest returns suggest that the further one goes in Finland the greater the discrepancy between the two, as a consequence of the increase in stumpage price differences. Thus, whereas the yield per hectare in North-Eastern Finland is about 20 % of that in Eastern Häme, the stumpage price is similarly only just over 50 % of that prevailing in the latter area. This, the resulting returns per hectare are only 10 % of those obtainable in the more southerly area. When the return per hectare for the Forestry Board District of Eastern Häme is represented by the index 100, one then obtains corresponding return indices of 21.0 for the Northern Ostrobothnia and Kainuu area, 13.0 for Lapland and 10.0 for North-Eastern Finland. Thus, it may be said that roughly 10 hectares of forest land in Lapland, 5 in Northern Ostrobothnia or Kainuu, or 2 in Northern Karelia or the coastal area of southern and central Ostrobothnia would be required to produce the same returns as 1 hectare in Eastern Häme. This represents an extremely wide range of variation within the borders of one country.

This work provides a clear and sufficiently accurate impression of the order of magnitude of the areal differences in returns from the Finnish forests, and may thus serve as an adequate basis for the taking of decisions in this field.

The PDF includes a summary in English.

• Alho, E-mail: pa@mm.unknown

Water extracts of six common soil lichens, Cladonia alpestris, C. rangiferina, C. arbuscula (sylvatica), C. pleurota, Cetraria islandica, Stereocaulon paschale, inhibited growth of ectomycorrhizae of Pinus sylvestris (L.). Of 17 fungi (12 mycorrhizal) tested, many were inhibited while others were scarcely influenced or even occasionally stimulated by the extracts. Cladonia alpestris extract inhibited most fungi while C. rangiferina showed much less influence.

In pure culture synthesis experiments, 32P uptake of Pinus sylvestris was significantly reduced by C. alpestris extract. Different species of fungi showed widely variant abilities to pick up 32 P. in nursery experiments, much more vigorous growth of P. sylvestris and Picea abies (L.) H. Karst. was obtained on plots without C. alpestris than on paired plots covered with it. Betula verrucosa (B. pendula Roth) showed no difference. Under natural forest conditions, P. sylvestris seedlings grow much more rapidly where C. alpestris had been eliminated by road building or reindeer grazing than do seedlings only one meter distant under undisturbed C. alpestris cover. It is suggested that by properly controlled reindeer grazing, establishment and early growth of P. sylvestris on Cladonia sites can be much enhanced. By the time that C. alpestris could become re-established the pine seedlings would have grown large enough to suffer little from reindeer grazing. This study shows the continuity of the major components of the forest tundra biome – the dependence of pines, mycorrhizae, lichens, and reindeer and their predators (human or otherwise) upon each other for a healthy existence.

The PDF includes a summary in Finnish.

• Brown, E-mail: rb@mm.unknown
• Mikola, E-mail: pm@mm.unknown

The article presents the studies about antagonistic influence of insect pathogenic fungi Beauveria bassiana (Bals.) Vuill. and B. tenella (Delacr.) Siem. against root rot diseases. The experiments were conducted in laboratory where the fungi were grown in Petri dishes. The results show that these fungi are antagonistic with each other. The used stem of B. bassiana was proved as strongest antagonist against all studied F.annosus.

The PDF contains a summary in German. 

• Laine, E-mail: ll@mm.unknown
• Nuorteva, E-mail: mn@mm.unknown

An investigation into the aerial distribution of Fomes annosus (now Heterbasidion annosum) in Finland was carried out. Prevalence of the fungus in the air was estimated from cultural counts of mycelia produced by diaspores which had fallen onto spruce discs and agar plates. The influence of climate on deposition of diaspores was determined from weather recordings.

For the main study, F. annosus diaspores collected from spruce stands in Helsinki, Anjala and Jokioinen were recorded at weekly or fortnightly intervals throughout 1968. Diaspores fell during the 24-hour periods almost continuously at all three observation sites from April to November, but the deposition was most frequent from late May to the end of October. The amounts of deposition varied greatly with the observation sites, seasons of the year, and time of the day. The fall was heaviest at Anjala and slightest at Jokioinen.

Throughout the season of deposition, more diaspores were trapped on all observation sites at night than during the day. A significant positive correlation was found between the fall of F. annosus diaspores and the air temperature. Diaspores of F. annosus were found in the forest on needles and leaves, and underneath the humus layer in mineral soil. The fall of diaspores decreased as the distance from sporophores increased.

The aerial distribution of two antagonists to F. annosus, viz. Peniophora gigantea and Trichoderma viride, was also studied. It was found that the diaspores of the former fell mainly during the same seasons as those of F. annosus.

• Kallio, E-mail: tk@mm.unknown

The purpose of this study was determining the optimum cutting program for forest stands by the application of dynamic programming. Calculations have been made for even-aged Scots pine (Pinus sylvestris L.) stands in Southern Finland, aged 50-100 years. Three logging cost levels, thinning from below and from above, and rates of interest of 1, 2, 3, 4, and 5% was applied. Both optimum routes and the economic results of different cutting programs was analysed.

According to the results, the higher the rate of interest is, the lower the density remains, and shorter the rotation is. The starting level of the growing stock may influence the treatment of the stand for tens of years. If logging costs change, so that harvesting small wood becomes relatively more expensive in the future, the density of growing stock will increase. However, heavy thinnings today are recommendable, to avoid expensive thinnings in the future.

The density of the growing stock should be higher if thinning from above is applied, instead of thinning from below. The growth of the stands thinned from below needs to be greater than the growth of stands thinned from above, to justify thinnings from below. Too high density often results in larger losses than do too low a density or the wrong rotation. Thinnings seem to be profitable even at much higher logging costs than those of today. The maturity of the stand is determined both by the age and the density of the growing stock. The stand may be mature because of great age, high density combined with a relatively high age, or because the growing stock is too low in density.

The PDF includes a summary in Finnish.

• Kilkki, E-mail: pk@mm.unknown
• Väisänen, E-mail: uv@mm.unknown

• Munna, Department of Soil and Geological Sciences, Sokoine University of Agriculture, P.O. Box 3008, Morogoro, Tanzania https://orcid.org/0000-0001-8858-0457 E-mail: amabmunna81@gmail.com
• Amuri, Department of Soil and Geological Sciences, Sokoine University of Agriculture, P.O. Box 3008, Morogoro, Tanzania https://orcid.org/0000-0003-3092-3458 E-mail: namuri@sua.ac.tz
• Hieronimo, Department of Agricultural Engineering, Sokoine University of Agriculture, P.O. Box 3003 Morogoro, Tanzania https://orcid.org/0000-0002-4450-5073 E-mail: phmusigula@gmail.com
• Woiso, Department of Biosciences, Sokoine University of Agriculture, P.O. Box 3038 Morogoro, Tanzania E-mail: dino@sua.ac.tz

• Tikkanen, School of Forest Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0002-3875-2772 E-mail: Olli-Pekka.Tikkanen@uef.fi
• Lehtonen, Finnish Meteorological Institute, P.O. Box 503, FI-00101 Helsinki, Finland https://orcid.org/0000-0001-7317-9580 E-mail: Ilari.Lehtonen@fmi.fi

This study’s aim was to calculate the weathering rates of Ca and Mg for five boreal forest soils in southern Finland on granitic and gabbro containing bedrock. The effect of mineralogy on the total concentrations of Ca and Mg in soil and weathering rates was evaluated. The aim was also to estimate the effect of mechanical soil disturbance related to ploughing on the weathering in the gabbro area. The total concentrations of SiO₂, CaO, MgO, and Zr were determined by XRF, and weathering rates of Ca and Mg were determined based on the changes in the CaO, MgO, and Zr concentrations. The weathering rates of Ca+Mg varied 5–38 mmol_c m^–2 year^–1 in the E+B/BC horizons among the plots. Soil disturbance related to ploughing increased the weathering of Ca and Mg largely in the disturbed part of the topmost mineral soil as indicated by the decreasing concentrations of Ca and Mg after mechanical soil disturbance. The weathering input of Ca in the undisturbed soil did not fully replace the Ca output in final whole-tree cutting. The weathering input of Mg in the undisturbed soil was sufficient to replace the lost Mg in stemwood harvesting but not on all the plots the lost Mg in whole-tree harvesting. Weathering rates were higher in the gabbro than the granitic areas.

• Lindroos, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: antti.lindroos@luke.fi
• Ilvesniemi, Natural Resources Institute Finland (Luke), Production systems, Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: hannu.ilvesniemi@luke.fi

Norway’s most common tree species, Picea abies (L.) Karst. (Norway spruce), is often infected with Heterobasidion parviporum Niemelä & Korhonen and Heterobasidion annosum (Fr.) Bref.. Because Pinus sylvestris L. (Scots pine) is less susceptible to rot, it is worth considering if converting rot-infested spruce stands to pine improves economic performance. We examined the economically optimal choice between planting Norway spruce and Scots pine for previously spruce-dominated clear-cut sites of different site indexes with initial rot levels varying from 0% to 100% of stumps on the site. While it is optimal to continue to plant Norway spruce in regions with low rot levels, shifting to Scots pine pays off when rot levels get higher. The threshold rot level for changing from Norway spruce to Scots pine increases with the site index. We present a case study demonstrating a practical method (“Precision forestry”) for determining the tree species in a stand at the pixel level when the stand is heterogeneous both in site indexes and rot levels. This method is consistent with the concept of Precision forestry, which aims to plan and execute site-specific forest management activities to improve the quality of wood products while minimising waste, increasing profits, and maintaining environmental quality. The material for the study includes data on rot levels and site indexes in 71 clear-cut stands. Compared to planting the entire stand with a single species, pixel-level optimised species selection increases the net present value in almost every stand, with average increase of approximately 6%.

• Aza, Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, PO Box 5003, NO-1432, Ås, Norway https://orcid.org/0000-0002-6416-6697 E-mail: anfe@nmbu.no
• Kallio, Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, PO Box 5003, NO-1432, Ås, Norway E-mail: maarit.kallio@nmbu.no
• Pukkala, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: timo.pukkala@uef.fi
• Hietala, Norwegian Institute of Bioeconomy Research, PO Box 115, NO-1431 Ås, Norway E-mail: ari.hietala@nibio.no
• Gobakken, Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, PO Box 5003, NO-1432, Ås, Norway E-mail: terje.gobakken@nmbu.no
• Astrup, Norwegian Institute of Bioeconomy Research, PO Box 115, NO-1431 Ås, Norway E-mail: rasmus.astrup@nibio.no

Pathogenic wood decay fungi such as species of Heterobasidion are some of the most serious forest pathogens in Europe, causing rot of tree boles and loss of growth, with estimated economic losses of eight hundred million euros per year. In conifers with low resinous heartwood such as species of Picea and Abies, these fungi are commonly confined to heartwood and thus external infection signs on the bark or foliage of trees are normally absent. Consequently, determining the extent of disease presence in a forest stand with field surveys is not practical for guiding forest management decisions such as optimal rotation time. Remote sensing technologies such as airborne laser scanning and aerial imagery are already used to reduce the reliance on fieldwork in forest inventories. This study aimed to use remote sensing to detect rot in spruce (Picea abies L. Karst.) forests in Norway. An airborne hyperspectral imager provided information for classifying the presence or absence of rot in a single-tree-based framework. Ground reference data showing the presence of rot were collected by harvest machine operators during the harvest of forest stands. Random forest and support vector machine algorithms were used to classify the presence and absence of rot. Results indicate a 64% overall classification accuracy for presence-absence classification of rot, although additional work remains to make the classifications usable for practical forest management.

• Allen, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: benjamin.allen@nmbu.no
• Dalponte, Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione E. Mach, Via E. Mach 1, 38098 San Michele all’Adige (TN), Italy E-mail: michele.dalponte@fmach.it
• Hietala, Norwegian Institute of Bioeconomy Research, Innocamp Steinkjer, Skolegata 22, NO-7713 Steinkjer, Norway E-mail: Ari.Hietala@nibio.no
• Ørka, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: hans-ole.orka@nmbu.no
• Næsset, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: erik.naesset@nmbu.no
• Gobakken, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: terje.gobakken@nmbu.no

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

Five Scots pine (Pinus sylvestris L.) progeny field trials, each established in different Lithuanian regions of provenance in 1983, were studied. Each progeny field trial consists of 140 half-sib families from seven populations (20 families from each population). The evaluation was carried out in 2012 and 2018 to assess the families resistance to Heterobasidion annosum (Fr.) Bref. An index of resistance in the infected plots was calculated. To verify the accuracy of the method, total phenolic compounds (TPC) was chosen as key parameter to compare with the plant resistance index. During the six years between the two assessments, the percentage of living Scots pine trees in the progeny field trials decreased up to 20 percentage points (range: 4 p.p. to 20 p.p.). In 2018 the area of H. annosum damaged plots (in percentage from total field trial area) varied from 17 to 27%. Tree mortality in the trial correlates with site soil fertility – more fertile soils were distinguished by higher tree percentage loss and vice versa. Using analysis from combined data of all progeny trials, the family variance component reached 13.3 ± 2.2% and family heritability was 0.81. Family heritability estimates for root rot resistance show possibilities of high breeding effectiveness. The correlations between the trials in family resistance estimates were negligible (ranging from 0 to 0.28). The significant high correlation coefficient was determined between the resistance index and TPC concentration (r = 0.77, p = 0.0003). This allows us to assume that plant resistance is directly linked on TPC synthesis. The results indicate that the chosen methods of chemical resistance for identification of root rot-resistant genotypes are applicable for the selection of Scots pine half-sib families in the field trials with higher resistance to pathogens.

• Marčiulynas, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: adas.marciulynas@mi.lt
• Sirgedaitė-Šėžienė, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: vaida.seziene@mi.lt
• Žemaitis, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: povilas.zemaitis@mi.lt
• Jansons, Latvian State Forest Research Institute “Silava”, Department of Forest Tree Breeding, Rigas St.t. 111, Salaspils LV-2169, Latvia E-mail: aris.jansons@silava.lv
• Baliuckas, Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, LT-53101 Girionys, Kaunas District, Lithuania E-mail: virgilijus.baliuckas@mi.lt

Considering the increasing use of wood biomass for energy and the related intensification of forest management, the impacts of different intensities of biomass harvesting on nutrient leaching risks must be better understood. Different nitrogen forms in the soil solution were monitored for 3 to 6 years after harvesting in hemiboreal forests in Latvia to evaluate the impacts of different biomass harvesting regimes on local nitrogen leaching risks, which potentially increase eutrophication in surface waters. In forestland dominated by Scots pine Pinus sylvestris L. or Norway spruce Picea abies L. (Karst.), the soil solution was sampled in: (i) stem-only harvesting (SOH), (ii) whole‐tree harvesting, with only slash removed (WTH), and (iii) whole‐tree harvesting, with both slash and stumps harvested (WTH + SB), subplots. In agricultural land, sampling was performed in an initially fertilised hybrid aspen (Populus tremula L.× P. tremuloides Michx.) short-rotation coppice (SRC), where above-ground biomass was harvested. In forestland, soil solution N (nitrogen) concentrations were highest in the second and third year after harvesting. Mean annual values in WTH subplots of medium to high fertility sites exceeded the mean values in SOH subplots and control subplots (mature stand where no harvesting was performed) for the entire study period; the opposite trend was observed for the low-fertility site. Biomass harvesting in the hybrid aspen SRC only slightly affected NO₃^–-N (nitrate nitrogen) and NH₄⁺-N (ammonium nitrogen) concentrations in the soil solution within 3 years after harvesting, but a significant decrease in the TN (total nitrogen) concentration in the soil solution was found in plots with additional N fertilisation performed once initially.

• Kļaviņš, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia; University of Latvia, Raiņa blvd 19-125, LV 1586, Riga, Latvia E-mail: ivars.klavins@silava.lv
• Bārdule, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia; University of Latvia, Raiņa blvd 19-125, LV 1586, Riga, Latvia E-mail: arta.bardule@silava.lv
• Lībiete, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: zane.libiete@silava.lv
• Lazdiņa, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: dagnija.lazdina@silava.lv
• Lazdiņš, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia E-mail: andis.lazdins@silava.lv

Yellowhorn (Xanthoceras sorbifolium Bunge) has been widely planted for biodiesel production in China, but has frequently shown poor field performance. Container-grown yellowhorn seedlings originating from three Chinese provenances, Wengniute Qi (WQ), Alukeerqin Qi (AQ), and Shanxian (SX), were fertilized with slow-release fertilizer (SRF) at 40, 80, 120, 160 or 200 mg N seedling^–1. Tree growth, survival and nutrient content were measured after one year’s growth in a greenhouse followed by two years in a field site. Plants from AQ and SX tended to have higher stem and root P contents in the nursery. Higher rates of SRF increased root N, and stem and root P contents. After one year in the nursery, there were a number of interactions between provenance and SRF for plant growth responses and nutrient content in the nursery, however after two years of additional growth in the field, plants from the different provenances generally responded similarly to applied SRF in the nursery, with few interactions. Final plant height was approximately 10% lower in trees from provenance SX but was not affected by application of SRF. Conversely, final trunk diameter and stem and root biomass were unaffected by provenance but increased with higher rates of applied SRF. Our results indicate that application of SRF may be a useful tool to nutrient load yellowhorn in the nursery and facilitate transplanting performance in the field. Overall, optimal nursery and field performance of yellowhorn were observed in provenance AQ at 120–200 mg N seedling^–1 SRF. We suggest that growers consider a wider range of yellowhorn provenances and SRF rates (above 200 mg N seedling^–1) to yield even better growth response.

• Ao, Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing Forestry University, 35 East Qinghua Road, Haidian District, Beijing 100083, China E-mail: aoyan316@163.com
• Hirst, Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907, USA E-mail: hirst@purdue.edu
• Li, Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing Forestry University, 35 East Qinghua Road, Haidian District, Beijing 100083, China E-mail: glli226@163.com
• Miao, Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing Forestry University, 35 East Qinghua Road, Haidian District, Beijing 100083, China E-mail: 372902610@qq.com
• Zhang, College of Forestry, Beijing Forestry University, 35 East Qinghua Road, Haidian District, Beijing 100083, China E-mail: 793755837@qq.com

The paper deals with production of above-ground biomass of silver birch (Betula pendula Roth) stands in the Czech Republic. One-year biomass dynamics was studied within chronosequence of birch stands at the age of 4–5, 8–9, 17–18 and 22–23 years. With the exception of the youngest stand, which was established by seeding, all experimental birch stands were regenerated naturally after the allochthonous spruce stands. Above-ground biomass (AB) was calculated from plot inventory data and biomass equations were parameterized from destructive sampling of biomass component of sampled trees. Results reveal that the peak of the mean annual increment (MAI_ABtotal) of birch stands can be expected at the age from 15 to 20 years. Additionally, the stand age, the value of basal area (BA) should be considered as a predictor of stand productivity. If the value of BA varied from 25 to 35 m² ha^–1, the MAI of the birch stands reached the range from 5.0 to 6.5 t of dry biomass per ha y^–1 at the age ranging between 15 and 25 years. The stem/branch proportion increased with stand age, the stem relative proportion ranging from 75 to 90% of total above-ground biomass. According to the results of this study, birch stand biomass production and utilization is one of the approaches in terms of forest recovery management in large disturbed areas. Although, no silvicultural treatments were occurred in all analysed stands, the pre-commercial thinning method could increase stand productivity and stability as well.

• Martiník, Department of Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, 613 00 Brno, Czech Republic https://orcid.org/0000-0002-5906-8830 E-mail: martinik@mendelu.cz
• Knott, Department of Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, 613 00 Brno, Czech Republic E-mail: robert.knott@mendelu.cz
• Krejza, Global Change Research Institute CAS, v.v.i., Bělidla 4a, 603 00 Brno, Czech Republic E-mail: krejza.j@czechglobe.cz
• Černý, The Forestry and Game Management Research Institute, Research Station at Opočno, Na Olivě 550, 517 73 Opočno, Czech Republic E-mail: cerny@vulhmop.cz

This study aimed at establishing calibrations to predict nutrient concentrations of solid moose (Alces alces L.) rumen content using near infrared spectroscopy (NIRS), as an alternative to expensive chemical analyses. NIR reflectance spectra of 148 dry pulverized samples were recorded. The scanned samples were then analyzed for crude protein, available protein, microbial nitrogen (N), ash, acid-detergent fiber (ADF), neutral detergent fiber (NDF) and lignin contents following standard chemical analysis procedures. The calibration models were derived by Orthogonal Projection to Latent Structure (OPLS) and validated using external prediction sets. The calibration models accurately predicted crude protein, available protein and ash contents (R² = 0.99, 0.96, and 0.92, prediction error = 0.39, 0.72 and 0.53% dry matter, respectively) while NDF (R² = 0.92; prediction error = 2.23% dry matter) and ADF (R² = 0.89; prediction error = 1.94% dry matter) were predicted with sufficient accuracy and that of microbial-N (R² = 0.81; prediction error = 1.25 mg yeast-RNA g^–1 dry matter) and lignin (R² = 0.84; prediction error = 1.05% dry matter) were acceptable. The ratio of performance to deviation values were > 3.0 for crude protein and available protein, between 3.0 and 2.5 for ADF, NDF and lignin, and 2.32 for microbial-N; attesting the robustness of the calibration models. It can be concluded that NIR spectroscopy offers a quick and inexpensive procedure for prediction of nutrient concentrations of solid rumen contents in wild herbivores.

• Tigabu, Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Box 49, SE-230 53 Alnarp, Sweden http://orcid.org/0000-0003-2471-1168 E-mail: mulualem.tigabu@slu.se
• Felton, Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Box 49, SE-230 53 Alnarp, Sweden E-mail: annika.felton@slu.se

In the southwest of the Iberian Peninsula, Phytophthora cinnamomi Rands is causing irreversible damage to populations of the two most common species of Quercus, the holm oak (Quercus ilex L.) and the cork oak (Quercus suber L.). Although the symptoms are similar in the two species, the mortality rates are different. We found significant differences in the post-infection growth of the root system as a function of tree species, as well as initial plant size, and inoculum level. We observed a marked decrease in the growth of new roots in Q. ilex with increasing inoculum level, while in Q. suber, we found longer but thinner roots with a moderate inoculum level. In both species, we observed a worsening in the water status of the plants from the lowest inoculum level.

• León, University of Huelva, Agroforestry department, Calle Dr. Cantero Cuadrado, 6, 21004 Huelva, Spain E-mail: isabel.leon@dcaf.uhu.es
• García, University of Huelva, Agroforestry department, Calle Dr. Cantero Cuadrado, 6, 21004 Huelva, Spain E-mail: juanjose.garcia@dcaf.uhu.es
• Fernández, University of Huelva, Agroforestry department, Calle Dr. Cantero Cuadrado, 6, 21004 Huelva, Spain E-mail: nonoe@uhu.es
• Vázquez-Piqué, University of Huelva, Agroforestry department, Calle Dr. Cantero Cuadrado, 6, 21004 Huelva, Spain E-mail: jpique@dcaf.uhu.es
• Tapias, University of Huelva, Agroforestry department, Calle Dr. Cantero Cuadrado, 6, 21004 Huelva, Spain E-mail: rtapias@uhu.es

Pruning was performed at midsummer in two genetically homogenous and managed planted silver birch stands in southern Sweden – one aged 9 and one aged 10 years. Wood defects were analysed 10 years thereafter, using the five uppermost twigs of the stems up to a height of 30 dm. The number of trees examined at each site was around 70, of which half were pruned. The main findings were that: a) compared to unpruned trees, pruned trees produced more defect-free wood outside the knots; b) most wood defects were found inside the knots; and c) wood defects like rot and bark ingrowth were similar for pruned and unpruned trees, while discolouration was marginally higher for pruned trees inside knots but similar outside knots. Overall, the results confirm previous findings that pruned birch trees will provide butt logs with higher value than unpruned trees.

• Stener, The Forestry Research Institute of Sweden, Ekebo 2250, 268 90 Svalöv, Sweden E-mail: lars-goran.stener@skogforsk.se
• Rytter, The Forestry Research Institute of Sweden, Ekebo 2250, 268 90 Svalöv, Sweden E-mail: lars.rytter@skogforsk.se
• Jansson, The Forestry Research Institute of Sweden, Uppsala Science Park, 751 83 Uppsala, Sweden E-mail: gunnar.jansson@skogforsk.se

A time study was conducted to determine whether stem crowding had any impact on harvester productivity in Eucalyptus grandis stands. This represents an important element when trying to balance the advantages and disadvantages of coppice management in fast growing plantations designated for mechanized harvesting (i.e. machine felling, delimbing, debarking and cross-cutting). The study material consisted of 446 coppice stems, half of which grew as single stems per stool and half as double stems per stool as a result of different coppice reduction strategies. The dataset was balanced and randomized, with both subsets replicating exactly the same stem size distribution and the single and double stems alternating randomly. Harvester productivity ranged between 6 and 50 m³ under bark per productive machine hour, following the variation of tree diameter from 10 to 40 cm at breast height (1.37 m according to South African standards). Regression analysis indicated that both tree size and stem crowding (e.g. one or two stems per stool) had a significant effect on harvester productivity, which increased with stem size and decreased with stem crowding. However, operator experience may overcome the effect of stem crowding, which was not significant when the harvester was manned by a highly experienced operator. In any case, the effect of stem size was much greater than that of stem crowding, which resulted in a cost difference of less than 10%. However, this figure excludes the possible effects of stem crowding on volume recovery and stem development, which should be addressed in the future.

• McEwan, Nelson Mandela Metropolitan University – George Campus, Saasveld, 6529, George, South Africa E-mail: Andrew.McEwan@nmmu.ac.za
• Magagnotti, CNR IVALSA, Via Madonna del Piano 10, I-50019 Sesto Fiorentino (FI), Italy E-mail: magagnotti@ivalsa.cnr.it
• Spinelli, CNR IVALSA, Via Madonna del Piano 10, I-50019 Sesto Fiorentino (FI), Italy E-mail: spinelli@ivalsa.cnr.it

• Skrøppa, Norwegian Forest and Landscape Institute, Box 115, 1431 Ås, Norway E-mail: tore.skroppa@skogoglandskap.no
• Solheim, Norwegian Forest and Landscape Institute, Box 115, 1431 Ås, Norway E-mail: halvor.solheim@skogoglandskap.no
• Steffenrem, Norwegian Forest and Landscape Institute, Box 115, 1431 Ås, Norway E-mail: arne.steffenrem@skogoglandskap.no

• Komonen, Department of Biological and Environmental Science, P.O. Box 35, FI-40014, University of Jyväskylä, Finland E-mail: atte.komonen@jyu.fi
• Halme, Department of Biological and Environmental Science, P.O. Box 35, FI-40014, University of Jyväskylä, Finland E-mail: panu.halme@jyu.fi
• Jäntti, Department of Biological and Environmental Science, P.O. Box 35, FI-40014, University of Jyväskylä, Finland E-mail: mari.j.jantti@student.jyu.fi
• Koskela, Department of Biological and Environmental Science, P.O. Box 35, FI-40014, University of Jyväskylä, Finland E-mail: tuuli.e.koskela@student.jyu.fi
• Kotiaho, Department of Biological and Environmental Science, P.O. Box 35, FI-40014, University of Jyväskylä, Finland E-mail: janne.kotiaho@jyu.fi
• Toivanen, Department of Biological and Environmental Science, P.O. Box 35, FI-40014, University of Jyväskylä, Finland; Current: Birdlife Finland, Annankatu 29 A 16, FI-00100 Helsinki, Finland E-mail: tero.toivanen@birdlife.fi

• Angelstam, School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden E-mail: per.angelstam@slu.se
• Andersson, School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden E-mail: ka@nn.se
• Axelsson, School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden E-mail: ra@nn.se
• Elbakidze, School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden E-mail: me@nn.se
• Jonsson, Dept of Natural Science, Engineering and Mathematics, Mid Sweden University, Sundsvall, Sweden E-mail: bgj@nn.se
• Roberge, Dept of Wildlife, Fish and Environmental Studies, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Umeå, Sweden E-mail: jmr@nn.se

• Tulokas, Centre for Timber Engineering, Edinburgh Napier University, 10 Colinton Road, Edinburgh EH10 5DT, UK E-mail: tomi.tulokas@lut.fi
• Tannous, School of Engineering and the Built Environment, Edinburgh Napier University, 10 Colinton Road, Edinburgh EH10 5DT, UK E-mail: jt@nn.uk

• Mola-Yudego, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: blas.mola@uef.fi

• Nagaike, Yamanashi Forest Research Institute, Masuho, Yamanashi 400-0502, Japan E-mail: nagaike-zty@pref.yamanashi.lg.jp

• Kurttila, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: mikko.kurttila@joensuu.fi
• Leskinen, Finnish Environment Institute, Research Programme for Production and Consumption, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: pl@nn.fi
• Pykäläinen, Metsämonex Ltd., Joensuu, Finland E-mail: jp@nn.fi
• Ruuskanen, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: tr@nn.fi

• Cienciala, Institute of Forest Ecosystem Research (IFER), Areal 1. Jilovske a.s. 1544, 254 01 Jilove u Prahy, Czech Republic E-mail: emil.cienciala@ifer.cz
• Tomppo, Metla, Finnish Forest Research Institute, Finland E-mail: et@nn.fi
• Snorrason, Icelandic Forest Research, Iceland E-mail: as@nn.is
• Broadmeadow, Forestry Commission, Forest Research Alice Holt Logdge, United Kingdom E-mail: mb@nn.uk
• Colin, French National Forest Inventory, France E-mail: ac@nn.fr
• Dunger, Federal Research Centre for Forestry and Forest Products, Institute of Forest Ecology and Forest Assessment, Germany E-mail: kd@nn.de
• Exnerova, Institute of Forest Ecosystem Research, Czech Republic E-mail: ze@nn.cz
• Lasserre, Department of Environment and Territory Sciences and Technologies, University of Molise, Italy E-mail: bl@nn.it
• Petersson, Swedish University of Agricultural Sciences, Department of Forest Resource Management, Sweden E-mail: hp@nn.se
• Priwitzer, National Forest Centre, Forest Research Institute. Slovak Republic E-mail: tb@nn.sk
• Sanchez, Forest Health Unit, General Directorate for Biodiversity, Environmental Ministry, Spain E-mail: gs@nn.es
• Ståhl, Swedish University of Agricultural Sciences, Department of Forest Resource Management, Sweden E-mail: gs@nn.se

• Rönnberg, SLU, Southern Swedish Forest Research Centre, P.O. Box 49, SE-23053 Alnarp, Sweden E-mail: jonas.ronnberg@ess.slu.se
• Berglund, SLU, Southern Swedish Forest Research Centre, P.O. Box 49, SE-23053 Alnarp, Sweden E-mail: mb@nn.se
• Johansson, Tönnersjöheden Experimental Forest, P.O. Box 17, SE-31038 Simlångsdalen, Sweden E-mail: uj@nn.se

• Püttsepp, Department of Ecology, Swedish University of Agricultural Sciences, P.O. Box 7072, SE-75007 Uppsala, Sweden; Estonian University of Life Sciences, Kreuzwaldi 64, Tartu 51014, Estonia E-mail: ulle.puttsepp@ekol.slu.se
• Lõhmus, Institute of Geography, University of Tartu, Vanemuise 46, Tartu 51014, Estonia E-mail: kl@nn.ee
• Koppel, Estonian University of Life Sciences, Kreuzwaldi 64, Tartu 51014, Estonia E-mail: ak@nn.ee

• Mattila, The Finnish Forest Research Institute, Joensuu Unit, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: um@nn.fi
• Nuutinen, The Finnish Forest Research Institute, Joensuu Unit, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: tn@nn.fi

• McCarthy, University of British Columbia, Forest Sciences Department, 2424 Main Mall, Vancouver, B.C., Canada V6T 1Z4 E-mail: jmccarthy@jesuits.ca
• Weetman, University of British Columbia, Forest Sciences Department, 2424 Main Mall, Vancouver, B.C., Canada V6T 1Z4 E-mail: gw@n.ca

• Nieminen, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: mika.nieminen@metla.fi
• Ahti, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: ea@nn.fi
• Nousiainen, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: hn@nn.fi
• Joensuu, Forestry Development Centre Tapio, Soidinkuja 4, FI-00700 Helsinki, Finland E-mail: sj@nn.fi
• Vuollekoski, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: mv@nn.fi

• Zhu, Qingyuan Station of Forest Ecology, Institute of Applied Ecology, the Chinese Academy of Sciences, No. 72 Wenhua Road, Shenyang 110016, P.R. China; Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan E-mail: jiaojunzhu@iae.ac.cn
• Gonda, Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan E-mail: yg@nn.jp
• Matsuzaki, Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan E-mail: tm@nn.jp
• Yamamoto, Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan E-mail: my@nn.jp

• Hantula, Finnish Forest Research Institute. Fax +358 9 8570 5531 E-mail: jarkko.hantula@metla.fi
• Vainio, Finnish Forest Research Institute. Fax +358 9 8570 5531 E-mail: ev@nn.fi

• Lindén, Southern Swedish Forest Research Centre c/o Asa Experimental Forest, SLU, S-360 30 Lammhult, Sweden E-mail: magnus.linden@ess.slu.se
• Vollbrecht, Southern Swedish Forest Research Centre c/o Asa Experimental Forest, SLU, S-360 30 Lammhult, Sweden E-mail: gv@nn.se

• Kurkela, Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: timo.kurkela@metla.fi

• Viherä-Aarnio, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box. 18, FIN-01301 Vantaa, Finland E-mail: anneli.vihera-aarnio@metla.fi
• Velling, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box. 18, FIN-01301 Vantaa, Finland E-mail: pv@nn.fi

• Kuboyama, Forestry and Forest Products Research Institute Tohoku Center, Nabeyashiki 72, Shimo-Kuriyagawa, Morioka, Iwate, 020-0123 Japan E-mail: kuboyama@ffpri-thk.affrc.go.jp
• Oka, Forestry and Forest Products Research Institute Tohoku Center, Nabeyashiki 72, Shimo-Kuriyagawa, Morioka, Iwate, 020-0123 Japan E-mail: ho@nn.jp

• Rönnberg, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, SE-230 53 Alnarp, Sweden E-mail: jonas.ronnberg@ess.slu.se

Saprotrophic wood-decaying abilities of Rigidoporus microporus (Polyporales, Basidiomycota) syn. Rigidoporus lignosus and the structural alterations induced in wood blocks of Hevea brasiliensis Muell. Arg were studied. Mass loss of wood blocks was analyzed after 3 and 6 months respectively and the patterns of decay by pathogenic and endophytic isolates of this fungus were investigated using light microscopy. Effects of temperature on growth of the isolates on malt extract agar were also investigated. The R. microporus isolated from a non-H. brasiliensis host caused the highest percentage mass loss (27.2% after 6 months), followed by isolates ED310 (21.1%) and M13 (15.7%), both collected from diseased H. brasiliensis plantations. The isolate initially identified as an endophyte showed very low saprotrophic wood decay capability (4.3% after 6 months). The optimal temperature for growth of the isolates was 30 °C; except for the endophytic isolate which showed highest growth at 25 °C. Wood samples degraded by the R. microporus isolates showed simultaneous attack of wood cell walls, typical of white rot fungi. Results of the study indicate variability in the wood degrading abilities of the isolates and the potential differences in their physiology are discussed. Our findings further support the need for a taxonomical revision of the Rigidoporus genus.

• Oghenekaro, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: abbot.oghenekaro@helsinki.fi
• Daniel, Department of Forest Products/Wood Science, Swedish University of Agricultural Sciences, P.O. Box 7008, SE-75007 Uppsala, Sweden E-mail: geoffrey.daniel@slu.se
• Asiegbu, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: fred.asiegbu@helsinki.fi

• Mc Carthy, Forestry Research Institute of Sweden, Skogforsk, Ekebo 2250, SE-268 90 Svalöv, Sweden & Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, P.O. Box 49, SE-230 53 Alnarp, Sweden E-mail: rebecka.mccarthy@skogforsk.se
• Ekö, Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, P.O. Box 49, SE-230 53 Alnarp, Sweden E-mail: Per.Magnus.Eko@slu.se
• Rytter, Forestry Research Institute of Sweden, Skogforsk, Ekebo 2250, SE-268 90 Svalöv, Sweden E-mail: lars.rytter@skogforsk.se

• Backlund, Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Skogsmarksgränd, SE-901 83 Umeå, Sweden E-mail: ingegerd.backlund@slu.se
• Bergsten, Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Skogsmarksgränd, SE-901 83 Umeå, Sweden E-mail: urban.bergsten@slu.se

• Chaitanya, Pt. Ravishankar Shukla University, Seed Biology Lab, School of Life Sciences, Raipur – 492 010 (M.P.), India E-mail: kskc@nn.in
• Keshavkant, Pt. Ravishankar Shukla University, Seed Biology Lab, School of Life Sciences, Raipur – 492 010 (M.P.), India E-mail: sk@n.in
• Naithani, Pt. Ravishankar Shukla University, Seed Biology Lab, School of Life Sciences, Raipur – 492 010 (M.P.), India E-mail: naithani@mantraonline.com

• Viherä-Aarnio, The Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: anneli.vihera-aarnio@metla.fi
• Velling, The Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: pv@nn.fi

• Rouvinen, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: sr@nn.fi
• Kouki, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: jari.kouki@joensuu.fi