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New possibilities of oak mildew (Microsphaera alphitoides) control were tested and compared with present methods. The results of three-year experiments in 6 localities (Cikar, Budkov, Planá nad Lužnicí, Vědomice, Voznice, Zadní Bor) clearly showed that the sulphur-based fungicides registered for the control of oak mildew (Sulikol K, Sulka) had a relatively good and stable effectiveness, and that two other newly tested preparations (Systhane 12 EC, Amistar) were even more effective when the percentage of infested plants did not exceed 2% (Systhane 12 EC) or 5% (Amistar) in any experimental locality. Their registration should be extended in this way. The biopreparations with fungicidal or fungistatic effects such as Supresivit, Polyversum and Ibefungin, known and used in forestry, showed that it was not possible to use them for oak mildew control, similar results were received in tentative testing of another preparation (PFR). Testing of preparations Bion 50 WG and Neem Triact 90 EC gave interesting and promising results. Besides their sufficient effectiveness in the control of oak infestation by the mildew, our experiments also indicated their generally positive influence on the health of plants; this could compensate their economic disadvantage compared to classical fungicides.

The paper summarises main ideas concerning the structure of natural forest ecosystems at middle altitudes and documents the changes of humus forms and their chemistry in the natural forest of Žákova hora National Nature Reserve, in typical selected parts with different tree species composition: European beech - Norway spruce. The species composition, age and spatial structure are discussed and analysis of the uppermost soil layer is done in particular parts of the natural forest regeneration cycle, of different stages respectively. We compared the amount and layer composition of surface humus and basic pedochemical characteristics of holorganic and upper mineral horizons. The results document changes in the character of humus forms as a consequence of the tree species change. On the contrary, a high portion of uncertainty as for the species, age and spatial structure follows from discussion about the structure of natural forests at middle altitudes.

Physical, chemical and microbiological properties of soils were studied in black walnut (Juglans nigra L.) stands and compared with those in stands of natural species composition, in mixed stands of black walnut with linden and in pure oak stands. The objectives were to consider a possibility of black walnut planting at floodplain sites in the alluvial area of Southern Moravia. The first results did not show any worsening of soil properties and soil production potential. A positive amelioration effect of soil- improving species was proved in black walnut stands.

The effects of soil conditioners TerraCottem, Frisol, Bio-algeen and fertilisers Silvamix Forte and Cererit on the survival rate and growth of European ash seedlings until the stage called established plantation were observed on two experimental plots with different anthropogenic substrates. Eight-year experiments showed that under the given conditions the tested agents fulfilled the declared effects only partially. The application of TerraCottem was statistically insignificant both in the survival rate and in the growth. In the applied dose, Frisol manifested itself as an agent that may cause problems with the survival of plants, but at the same time also as a preparation improving the overall growth of young plants statistically significantly. Its effective dosage largely depends on the soil character. Bio-algeen had a very good effect on the survival rate of plants, but it did not surpass the control plants in the initial growth of plants. Silvamix Forte did not cause the mortality of seedlings and influenced the growth of plants statistically significantly for 1-3 years. In the applied dose, Cererit caused a high mortality of seedlings. The application of soil conditioners and Silvamix Forte did not markedly accelerate the growth and development until the stage of the established plantation. Until that time, the costs of the application of conditioners were higher by 4-13% as compared with the costs in the control plants.

Extensive forest areas were ameliorated by large-scale liming in the last years in order to prevent proceeding acidification and degradation of forest soils. The hitherto knowledge of liming effects on the function of forest soils still appears insufficient for an unambiguous evaluation. Sorption properties of soils and acidity are favourably affected by liming and the favourable effect is usually manifested in the layer of forest floor humus and in mineral soil within ten years. Reduction of soil acidity stimulates development of a bacterial component of microflora, soil edaphon, and good prerequisites are formed for a release of nutrients from soil organic matter. Improvement of some physical parameters of soils and negative effect of liming on the depth of rooting in spruce, availability of nutrients at some sites and in connection with mechanical soil preparation were also described. A key point of liming effect on forest soils is nitrogen dynamics. Mineralization of nitrogen is stimulated at nitrogen-rich sites with C/N < 30. Nitrogen-limited sites show nitrogen mineralization inhibited by liming with signs of pronounced deficiency in spruce nutrition. A positive effect of liming on nutrition with bases is generally accompanied by an adverse influence on N dynamics in acidic soils under spruce monocultures. Therefore it is possible to state that liming induces relatively marked changes in the soil but the actual growth response of woody species cannot be derived only from these changes.

The paper documents the effects of forest stands of different species composition on the humus form state and soil profile chemistry. It compares the situation in mixed broadleaved (ash, oak, hornbeam), basswood and spruce stands. Spruce demonstrates the site degradation effects: raw humus accumulation, soil acidification, negative effects on nutrient dynamics. Both broadleaved stands were similar as for site effects, lower litter accumulation, more rapid organic matter mineralization and more rapid nutrient cycling and intense uptake were documented in the basswood stand.

A large crown is one of the most important prerequisites for the good growth of a tree and therefore the crown could be called an engine of increment. The care for a large crown brings a decrease in the bole value at the same time as it makes large branches and later knots on it. Pruning is a possible solution of these two contradictions. Young wild cherry trees were pruned in three different ways: (i) half of the crown left, (ii) one quarter of the crown left and (iii) control, i.e. no pruning. The results show that height growth was not influenced by pruning while diameter growth was significantly affected. The crown reduction to a half means 10% less in diameter growth within a 5-year period after pruning. The crown reduction to one quarter of the crown means only two thirds of 'full' diameter growth on the control plot. The data suggest that the pruning of young wild cherry trees should be done moderately (more than a half of the crown should be left) and pruning should be done when the bottom part of the crown is in the shadow zone of the crown layer, not earlier.

The red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Scolytidae), was found for the first time in China in Yangcheng and Xinshui counties, Shanxi province in 1998, and in Hebei province in 1999. The beetle mostly attacks the oil pine Pinus tabulaeformis Carriére. By 2003 the beetle was found in 85 counties of three provinces in north China and the area of infested pine forests covered more than 700,000 ha. The elevation above sea level of forests infested is more than 800 m. The beetles most frequently attack trees on hilltops and at the forest edge, fewer attacks occur in the centre of the stand. This correlates with the damage done to the trees by wind or man. Weak and dying trees are more vulnerable to attack than healthy ones. The most attractive breeding sites are fresh stumps. The population density of the beetles is higher in the forests on northern slopes than on southern slopes. Most of the bores in the trunk are less than 0.5 m above ground; the galleries are found also on roots.

The paper evaluates the growth, structure, production, quality, leaf area index and dendrochronology of 100 years old Austrian pine (Pinus nigra ARNOLD) monoculture situated in the forest type group Fageto-Quercetum in the locality Horné Lefantovce (Nitrianska Streda Forest District, Topoľčianky Forest Enterprise). Codominant trees, trees with stem of high quality, with medium-sized crown, medium dense and straight crown are the most abundant in the stand. The tree number in the stand is 1,024 trees/ha, basal area 51.75 m2/ha, growing stock 571.56 m3/ha, aboveground biomass stock 348.76 t/ha and leaf area index 21.85 ha/ha. Dendrochronological analyses examined the response in individual sample trees and minimum annual ring width was found in 1920, 1922, 1925, 1929, 1933, 1938, 1944, 1946, 1947, 1949, 1952, 1954, 1963, 1968, 1976, 1982, 1990, 1993, 1998, 2001. Marked maximum values of annual ring width in the years 1919, 1923, 1926, 1930, 1936, 1937, 1941, 1948, 1951, 1955, 1959, 1966, 1972, 1975, 1980, 1985, 1997 were found as a positive productive feature. Beginning in the year 1993, dry Austrian pine trees occurred in the stand as a result of the fungal infection by Sphaeropsis sapinea (Fr.) Dyko et Sutton.

The condition was evaluated of tissues of declining young spruce stands in selected localities of the Orlické hory Mts. It refers to stands occurring in top parts affected by an air pollution disaster in the last century. Several types of damage of a different symptomatic character were distinguished. A high NO_x input appears to be the risk factor of spruce dieback in the Orlické hory Mts. One of the main causes in the complex of factors is the unbalanced cause of meteorological factors during the year and unbalance in mineral nutrition. The result is decrease in lignification, immaturity of tissues before the winter period and increased susceptibility of damaged tissues to parasites. Several potentially pathogenic species of micromycetes have been identified which can be considered to be significant pathogenic agents in case of declining spruce in the Orlické hory Mts., however, not a main cause.

This article presents a review of data and results of investigations from the period 1958-2006 regarding the occurrence of insects of the genus Cephalcia Panzer (Hymenoptera, Pamphiliidae) in Norway spruce stands of the Beskidy Mountains (Western Carpathians, southern Poland). Currently, eight species are known for the area: C. abietis, C. alashanica, C. alpina, C. annulicornis, C. arvensis, C. erythrogaster, C. fulva and C. masuttii. Information regarding each species is given, with details on identification, local occurrence and importance.

Yellowing of the Norway spruce is a relatively common problem in many areas of the Czech Republic. In some of them, it is also connected with forest decline; it was studied in the Šumava (Bohemian Forest) Mts. and in the western part of the Krušné hory Mts. This unfavourable phenomenon is initiated by several ecological as well as anthropic processes, one of the most important being the imbalance of forest stand nutrition. Particular reasons lead to the deficiency of nutrients, especially of magnesium. Solution of this undesirable trend is the profound ecological analysis and cause-oriented treatments. Besides lowering the air pollutant input, fertilization with deficient nutrients is a successful treatment in the forest stand management in affected areas. In the areas of interest, the application of a relatively small amount of appropriate fertilizer (SILVAMIX Mg) led to considerable improvement in the defoliation dynamics and yellowing progress since the first years after use.

Observations of the beech assimilatory apparatus in different levels of a model tree were realised from 1993 to 1999 in a research demonstration plot situated in Poľana. Different observations of the natural ecosystem condition were carried out. A model beech tree was chosen and marked as No. 228 for the above-mentioned analyses. The different ecophysiological and morphological characteristics of beech leaves were analysed in three (or two) tree crown levels. The results confirmed significant differences in these characteristics in dependence on three crown levels of mature beech tree. The differences in the mentioned characteristics were also shown in the course of particular years of research. In this paper we have presented the results of analysed beech leaves, their average maximum length, width, their average area, thickness, chlorophyll fluorescence during the research period.

Different transformations of RGB colour space were compared to develop the best method for discrimination of vegetation from the background in open pure cork oak stands in southern Portugal in high-resolution colour imagery. Normalised difference index, i1i2i3 colour space and other indices developed for classic band imagery were recalculated for near infrared imagery and tested. A new method for fully automated thresholding was developed and tested. The newly developed index shows the equal accuracy performance but provides the smallest overestimation error and retains the largest scale of grey levels for a subsequent shape analysis.

The United Nations Framework Convention on Climate Change accepted in 1992 at the Earth Summit in Rio de Janeiro provides principles and framework for cooperative international action on mitigating climate change. But it soon became clear that more radical targets were needed to encourage particular countries to reduce greenhouse gas emissions. In response, countries that have ratified the United Nation Framework Convention on Climate Change accepted the Kyoto Protocol in 1997. The rulebook for how the Kyoto Protocol will be implemented - the Marrakech Accord, was agreed in 2001. This paper describes political instruments and facilities of mitigating climate change by forestry proposed in those political documents.

A decline of macromycetes, especially of ectomycorrhizal species, has been described in the last decade in various parts of Europe. These changes are attributed to direct or indirect effects of air pollution. In Central Europe these changes correlate with visual damage of forest. Many ectomycorrhizal fungi seem to be very suitable bioindicators of the disturbance of forest ectotrophic stability. Stages of this disturbance can be linked directly to particular phases of impoverishment of ectomycorrhizal mycocoenoses. These conclusions have been obtained from long-term research on permanent plots (1,000-2,500 m²) in spruce and oak forests in the Czech Republic, but it seems that they are valid generally. For the quantification and study of mycorrhizal activity a special method has been developed and applied. The analyses of mycorrhizas from the same plots in the period 2000-2002 indicate large mycorrhizal dynamics. These data correlate with data obtained from a fruiting bodies survey. Both the percentage of ectomycorrhizal species and the ratio of active mycorrhizas are highly sensitive to outer impacts (air pollution, acidification, fertilization). Their decrease is in correlation with the strong defoliation of trees and can be used for the prediction of further development in comparable stands.

The spreading of bulldozer-formed windrows represents a second stage of the site restoration with bulldozers utilization in the Ore Mts. In the first period, bulldozers were used to create windrows for mechanized reforestation of immission-declined stands, causing profound devastation of forest sites, because removed surface humus was the only source of nutrients and environment for tree species roots. Preparatory stands have been established, and have to undergo re-construction in the coming years. Nowadays, the windrows are spread by the bulldozers again, covering 1/3 f the whole area between windrows by the rest of holorganic matter. This substratum is impoverished by the extensive mineralization and connected nutrient (especially N) losses, representing differently suitable space for tree rooting. Presented paper documents the effects of fertilization by different types of the SILVAMIX fertilizer on the growth and prosperity of new spruce plantations. Effects of fertilization are visible very soon and they are significantly beneficial for the new forest plantations.

During the construction of model logging costs for valuation of forest stands, by accident I found out differences between some species included in the groups of tree species. Differences within the groups of species may cause errors in logging costs of some species, for example with hornbeam, all species of linden, all species of rowans and horse chestnut. With the help of simple calculations it was proved that the differences could be very large, that they were more than forty per cent, it means they were significant. On the basis of my further research it is envisaged to increase the number of groups of trees from 13 to 16. The purpose is to give the most accurate background to make up a model of logging costs. In the second step it is expected that the model can provide the results for more or fewer groups of trees more easily if statistical methods are used. But this problem is not a part of this paper.

About 15% of the area of the Czech Republic is classified as territories with special status of protection, most of which is covered with forests. At present, at the time of integration of the country into the European structures, an increase in the area of such territories by approximately 20% is expected. The territories show significant variation of protection objectives, management restrictions, profound differentiation in natural conditions, structure of ownership and different levels of damage, especially that caused by anthropogenic pressure. This situation requires the formulation of long-term management strategies. The problem can be solved in the following successive steps: formulation of variants and alternatives of management strategies based on a retrospective analysis of forest development; prognosis of the forest condition development after application of the individual management strategies on the basis of growth and development simulations; addition of technological and economical bases; selection of optimal variants and alternatives from the viewpoint of the fulfilment of the owner's management goals, in accordance with the principles of forest policy and from the viewpoint of the fulfilment of the protection objective formulated for a specific territory with special status of protection. A set of methods for following the above-mentioned steps is specified in the presented contribution.

In 2002, height and diameter growth of spruce was investigated in the Orlické hory Mts. (the Czech Republic). The aim was to confirm and to quantify a growth increase in stands of different age, and to reveal the relation between growth and climate, and level of nitrogen deposition. Stem analyses of ten sample trees of mature spruce stand (average age 163 years) confirmed a significant increase in height and diameter growth since the mid-eighties of the 20^th century. Nearly 75% of radial increment variability could be explained by climatic factors. Growth in the last 10 years corresponded well to weather conditions. Analysis of the growth - nitrogen deposition relationship showed negative correlations, but the results were not statistically significant. Comparison of the height growth curves of young stands (11-47 years) proved that the younger the stand, the steeper the growth curve. The height of the youngest stands was on average the double of the height of older stands at the same age. The values of the height growth of young stands significantly overreached the yield table values in all the age classes analyzed.

A long-term study carried out within the 1967 All-Poland Larch Provenance Experiment investigated genetic variation in 20 Polish provenances of larch growing under the site conditions of the Beskid Sądecki Mts. (at a test site in Krynica). The study was based on the measurements of tree height made in individual larch populations during 1969-1999, i.e. when trees were 5, 8, 11, 15, 20, 25, 30 and 35 years old. The results showed a considerable adaptation stability of the provenances tested at the Krynica site. This stability, however, tended to decrease with increasing mean height of trees. An estimation of the effect of the "genotype (provenance) × years of observation (age)" interaction revealed a high stability of height growth in larch populations having extreme values of this trait. As follows from the study, it is possible, especially in the case of the latter group of provenances, to carry out effective selection in the early stage of tree growth, thus ensuring a permanent genetic gain.

Dothistroma needle blight Mycosphaerella pini is an important pathogen of pine needles. In addition to different species of pine, M. pini was found in blue spruce Picea pungens in the proximity of infected Pinus nigra in the region of southern Moravia about 20 km SE of Brno.

The paper presents the results of evaluating the growth and health of 20 different poplars from the Aigeiros group in 30-year populetum Leles on uninundated alluvia of the Latorica River in ecological conditions of the lowland Východoslovenská nížina. The populetum is situated on medium-heavy loamy soils in the group of forest site types Ulmeto-Fraxinetum carpineum. The results of evaluation document that out of the investigated poplar clones the poplars I-214, I-476, Blanc du Poitou, Flachslanden and P. nigra (Baka 5) had the best height and diameter growth and maximum volume production. Their health status was also very good. The lowest volume production was determined in P. nigra (009/66 ČR), I-455 and Grandis, and the worst health was found out in Grandis, P. nigra (Pavlovce 1) and P. nigra (Ivachnova 1). These results will facilitate to include the poplars I-476 and Flachslanden in the assortment of regionalized poplars for the lowland area of Východoslovenská nížina.

This is the first report on measurements and observations of an experimental plot of 35-year-old Norway spruce, established in 1970 by the Institute of Dendrology at Kórnik, where progenies of 22 plustrees from the Kłodzko Forest District were planted. The experiment was established in an incomplete block design of 20 families with 3 replications. Survival rate and growth traits determining productivity (plant height or basal area - stem cross-sectional area at breast height per 1 ha) were assessed in several years, and qualitative traits (trunk straightness; degree of natural pruning; thickness, length and angle of branches; crown density; presence of galls caused by the aphids Adelges laricis Vall. and Sacchiphantes viridis Ratz.) were evaluated once in 2001. Analysis of variance revealed significant differences between the half-sib families in survival rate and productivity but no significant differences in qualitative traits. Statistically significant positive correlations were found between trunk straightness at the age of 36 years and height of 2-year-old seedlings in the nursery, and between the degree of natural pruning at the age of 36 years and both tree height at the age of 9 years and basal area at the age of 13 years.

In changing growth conditions, methodical procedures should concentrate on the investigation of processes currently under way in forests. Many studies have shown that present models of forest growth parameters differ from previous surveys as far as for instance the height is concerned. Causes of these phenomena have not been satisfactorily explained although various hypotheses are investigated. In our study, we present partial results of the investigation of height growth within a sixty-five-year period, based on the analysis of data obtained from seven forest management plans in the management-plan area of Kostelec nad Černými lesy (Kostelec n. Č. l.) and continuous measurements on pilot research plots in the period of 1965-1994. The comparison of mean height growth curves obtained by the curve fitting of the values of empirical data signifies by their different course and increasing kurtosis a dependence on the calendar year when the measure was taken. It signifies an increasing height growth trend of both species in the given area.

This paper deals with large-scale mountain forest decline in the Šumava National Park. The changes in biotic and abiotic properties of forest sites follow the tree layer disintegration. Changed microclimatic conditions such as intensity of irradiance, moisture and temperature of the top holorganic layers together with altered development of ground vegetation could strongly affect the values of microbiological respiration activity and the rates of nitrogen mineralization and nitrification. Soil substrates, built of organic mater, located on stony locations, are endangered by introskeletal erosion. This paper compares these features in pairs of research plots, consisting of dead or cut forest and of living stand. According to the results of this study, higher rates of organic matter decomposition, transformed dynamics of nitrogen and other nutrients and possible nutrient leaching from soil solutions were demonstrated in the forest floor under declined spruce stands. The extent and seriousness of these adverse processes for forest soils are strongly site dependent.

The paper deals with the determination of the rate of damage by deer barking and browsing, the subsequent rot caused by Stereum sanguinolentum and the rate of its progress, elucidates causes of damage and quantifies volume and financial losses in the region of Forest Range Mořkov, Forest District Frenštát pod Radhoštěm. In the most damaged 2^nd age class, decay by Stereum sanguinolentum was recorded in 59% of damaged trees. The progress of rot ranged from 1 to 70 cm/year. The high number of red deer is considered to be the main reason of extensive damage by bark stripping in the Forest Range Mořkov. The actual financial loss caused by depreciation of wood by the rot is greatest in the 5^th age class amounting to CZK 64,320 per ha.

Restoration of forest soil character after the change of agricultural land use has not been studied yet despite the large areas reforested since the late 40ies of the last century. This process takes place throughout Europe to an increasing extent at present. The reformation of forest soils was studied in the area of Český Rudolec town: Natural Forest Area 16 - Czech-Moravian Uplands, altitude 600-630 m a.s.l., bedrock is built of granites and gneisses, soil type is Cambisol, forest site type 5K1. The process of restoration of a new humus form was analysed in plantations of American red oak (Quercus rubra), Swedish birch (Betula pendula), European larch (Larix europea) and Norway spruce (Picea abies), the site was homogeneous. The particular tree species accumulated 12.81, 13.81, 46.57 and 44.76 t/ha of surface organic matter during the last 30-40 years, these values are typical of forest sites at lower and middle altitudes and corresponding tree species composition. The effect of broadleaved species and conifers was markedly different, in the first case pH in KCl ranged 3.8-3.9 (mineral soil) and 3.5-5.2 (holorganic horizons), being 3.5-3.8 (mineral soil) and 3.1-5.1 (holorganic layers) for the conifers. Visible effects of the particular tree species were also evident in the soil adsorption complex and in the contents of plant available and total nutrients. The results can be summarised and generalised: - the forest soil character is reformed at lower and middle altitudes in a relatively short time from the aspect of surface humus accumulation and basic soil chemistry (30-40 years), - birch exhibited the best revitalisation effect among the studied species, - American red oak and Norway spruce humus accumulation potentials were different although the soil chemistry was comparable, - Norway spruce did not show a remarkable degradation effect until now, - on the contrary, European larch appeared as a site degrading species.

The investigations were conducted in the frame of EU Research project Wood for Energy - a Contribution to the Development of Sustainable Forest Management (2001-2005). The integrated wood ash experiment was set up in a 38-year-old Scots pine (Pinus sylvestris L.) stand on Arenosols in SW part of Lithuania. Raw (not hardened) wood ash and nitrogen fertilizers were applied in 6 variants: 1.25 t ash/ha; 2.5 t ash/ha; 5.0 t ash/ha; 180 kg N/ha; 2.5 t ash + 180 kg N/ha and control (no treatment). The changes of soil pH, the content of some nutrients, heavy metals in Arenosols and soil solution, the abundance of ammonifiers, nitrifiers and denitrifiers in forest floor and mineral topsoil after the application of wood ash are presented and discussed in this paper.

Social functions of forests were evaluated at Židlochovice Forest Enterprise by applying the method of Vyskot et al. (1996-2002). Real potentials of social forest functions were determined for all stand groups included in a forest management plan (FMP). The results of evaluation were processed in a database and projected in GIS. Tables and charts were used for the evaluation of results. We can claim on the basis of the results that the forest stands of the examined area are characterized by a very high potential to fulfil a bio-production social function. On the contrary, they have a low potential to fulfil social functions of ecological stabilization and edaphic soil conservation and hydric-hydrological function. The results of evaluation of the real potentials of social forest functions at Židlochovice Forest Enterprise are represented by the forest stands of management group No. 19 of forest management plan area Židlochovice.