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Forests have been subject to human intervention since the inception of human civilization. With enhanced knowledge, understanding and capacity humans exert an increasing pressure and influence on forests. Forests in general have undergone different ownership patterns. The requirements for forests have changed over time. The objectives of forest management are shifting from timber production to biodiversity conservation and nature protection. On the other hand, in many places the forests are dwindling due to the anthropic pressure. The management paradigms are changing in response to these triggering mechanisms. In this paper an attempt has been made to summarize the evolution of forest management practices and discuss some recent trends in forest management.

At present, photogrammetric interpretation of aerial images is a dominant method of forestry mapping. In the last years, transition from analogue to digital photogrammetry has been distinct. Digital photogrammetry enables to achieve workflow effectivity, and so to decrease the final product costs. The objective of the submitted paper was to evaluate the availability of digital photogrammetry for the forestry mapping rationalization. Digital aerotriangulation using the ImageStation SSK system brings more accurate results without requirements for the use of a larger amount of control points. The results also demonstrated the use of colour infrared aerial images, and also black and white aerial images at the scale 1:15,000 for the orthoimage creation in the forestry mapping department. Compared with the black and white aerial images, the colour infrared images have an essentially more interesting content, mainly from the qualitative aspect, which shifts them to use in many forestry disciplines (mostly for determination of the health conditions of forests stands, …), in combination with the remote sensing of the Earth and GIS (Geographic Information Systems).

Humans should behave in such a way that they will not endanger the existence of other living entities. After all, human activities affected the tree species composition and wildlife living conditions. Humans are now responsible for the preservation of delicate equilibrium in nature. Two localities were chosen for the research of game damage caused to standing trees - shooting areas Lužánky and Červený jelen, both situated in the vicinity of Jindřichův Hradec in South Bohemia. Seasonal character of tree-damage origin as well as its relation to the chemical content of spruce (Picea abies [L.] Karst.) and pine (Pinus sylvestris [L.]) bark were investigated. This area is typical of high game stock; trees are damaged by browsing and bark stripping. Particular advice for game management with respect to minimizing tree damage is presented. The data set of chemical bark analyses was statistically evaluated by t- and F-test and significant differences in element contents were detected between damaged and undamaged pine bark for N-substances (P = 0.003309), Ca (P = 0.001460), P (P = 0.004343), Mg (P = 0.001419) and K (P = 0.016290). Humans have influenced many changes in the distribution of different animal and plant species. Among others they are responsible for the altered species composition. Typically the extinction of large predators produces changes in food chains. In forest stands influenced by human activities the reasonable game management and the regulation of game stock seems to be one of the main tools in forest protection.

The paper deals with cambioxylophagous insects on Scots pine (Pinus sylvestris L.) trees. Research was conducted in forest stands growing on steep slopes on the left bank of the Otava River about 1 km north of Písek. These are nearly unmanaged stands of a special-purpose function with the natural occurrence of Scots pine. In total, twenty standing trees at 60 to 160 years of age that died after the spell of drought in 2003 were analysed. The composition of the community of cambioxylophagous insects was recorded in detail. The frequencies of occurrence of particular insect species were determined. In total, 34 species of cambioxylophagous insects were recorded. The order Coleoptera was quite a dominant group and within the order bark beetles (Scolytidae) and longhorn beetles (Cerambycidae) prevailed. The median of the species developing on one tree was 11. Tomicus piniperda (L.) was markedly the most frequent species with the frequency of occurrence 90%. Based on the composition of the communities of cambioxylophagous insects the potential importance of the insect in the decline of the analysed Scots pine trees was evaluated. Cambioxylophagous insects probably played a secondary role there.

Vegetative propagation of forest tree species is of great importance not only for breeding programmes but also for the conservation of valuable populations of tree species. Important is also a possibility of improving the genetic quality of established stands. Beech is a tree species that can substantially increase the stability of forest ecosystems. Minimal information is available about the ontogenesis of rooted cuttings of beech in forest stands for the time being. In our experiments that were gradually established since 1993 we acquired the first significant results of the evaluation of health status, phenological phenomena and growth of these plants. Our findings indicate that it is possible to use rooted cuttings as an element stabilising man-made forest stands including the transferred genetic quality. The evaluation of the 2^nd generation rooted cuttings of beech also provided positive results.

Frisol forte (FR F) and Frisol active (FR A) are slow-acting organic fertilisers recommended for reclamation and revitalisation of undeveloped soils and degraded areas. Tentative results of experiments carried out with these products on spoil banks in the CR showed controversial reactions of plants - on the one hand a high mortality of seedlings and a very good growth on the other. Reasons for these disproportions projecting themselves into the welfare of woody plants probably lie in an incorrect dosage of products. Thus, a special long-term experiment was established with the objective to find an optimal dosing to be used in practice for the reclamation process on spoil banks. By the method of measuring and statistical evaluation of height and stem diameter growths it was discovered that the best results were achieved by the combined use of both products with a dosage in the range of 30-60 g FR F + 250 ml FR A/5 l of water/10 seedlings. The discovered dosage is lower than that indicated by the manufacturer and literature. The application of granulated FR F alone was not so effective. The best dosage in this case was also 60 g/seedling. A disadvantage of using the combination of both types of Frisol is that the water required for dissolving the FR A liquid concentrate is not always available in the location being reforested.

The present paper deals with derivation of target stocking in forests of Norway spruce vegetation zone. Target stocking in forests with prevailing ecological and social functions is the stocking when the forest fulfils demanded functions in the best way. For forests in the Norway spruce vegetation zone target stocking was derived by original procedures as an optimum stocking in harmonization of demands on the fulfilment of ecological functions (especially erosion control, hydrological and water protection ones), securing static stability and preconditions for the formation and growth of natural regeneration. We investigated the relations between stocking and indicators of static stability (slenderness coefficient and ratio of crown length to tree height), natural regeneration phases, ground and non-wood vegetation coverage and natural regeneration coverage. The most favourable status of these indicators was found out in stocking 0.7 and in the upper forest limit 0.6.

Damage caused by bark peeling and browsing by red deer to Picea abies was investigated in two localities in the Českomoravská vrchovina Highlands. 127 experimental plots of 50 × 50 m in size were monitored in stands aged from 15 to 93 years. In total, 44% of 16,700 inspected trees were damaged by bark peeling and browsing. The area of gaping wounds varied from 50 to 1,650 cm². Stem decay affected 68% of the damaged trees. Some properties of the decay were analysed from 200 sample trees felled on the plots. Bark peeling damage occurred when the trees were 4 to 48 years old. Decayed wood accounted for 22-70% (mean 42%) of the merchantable stem volume of sample trees. The mean rate of the vertical decay spread was 17.4 cm per year (ranging from 4-63 cm per year). Mean decay volume correlated positively and mean spreading rate correlated negatively with the time elapsed from the bark peeling damage occurrence.

Effective forest management demands detailed knowledge of resources. Local forest users are usually the best source of information. In the Democratic Republic of Congo forest management partnerships between local people and government staff have become more common. A proper understanding of local perceptions of the forest is needed. This study was designed and guided by a multidisciplinary team including a sociologist, a linguist and a forester. It identified and compared classification and management units. It also touched on the different uses of the forest products, the species that provided these products and the locations of these species.

The objective of the study was to evaluate the growth potential of Carpathian birch (Betula carpatica W. et K.) at an environmentally harsh mountain site and a response of this species to altered soil chemistry after dolomitic limestone and basalt grit applications. The Carpathian birch proved to be a suitable species for the replanting of extreme acidic mountain sites. This birch shows a low mortality rate, grows well in the clear-felled patches and soon forms a cover which is necessary for the reintroducing of more sensitive tree species. The application of dolomitic limestone and basalt grit resulted in the slower growth of Carpathian birch plantations. Liming raised soil reaction, sum of exchangeable bases, base saturation, cation exchange capacity and reduced exchangeable Al content. On the other hand, liming decreased an amount of oxidizable soil organic matter and negatively affected soil N, exchangeable P and K. Basalt grit increased exchangeable P and K contents and raised soil reaction, however only slightly. The influence of basalt grit on the sum of exchangeable bases, base saturation and cation exchange capacity was also less pronounced compared to liming. Basalt grit elevated the proportion of exchangeable aluminium and reduced the content of soil N.

The paper describes the policy, legislative and organisational context and structure of financing the forestry from public funds in the Czech Republic, Estonia, Poland and Slovenia in the 90's. The first half of the nineties was the period of the most significant changes, whereas more stable and systematic financing of forestry was generally started in the second half of the nineties. The supported activities reflected main problems and challenges facing the forestry in individual countries. In the Czech Republic the substantial support was designed for protective measures and restitution of damaged stands. In Poland, the increase of forest area and restitution of forest stands damaged by air-pollution were the priority. Slovenian budget supported mainly the improvement of road infrastructure, forest management planning, as well as sustainable utilisation of forests through marking of trees for cutting. Estonian forestry received the relatively lowest subsidies allocated mainly to the preparation of management plans and extension services. Subsidies were the most important instruments of support. In Poland, however, tax exemptions and concessions were significantly higher than the value of financial means allocated from the public funds.

The influence of the date of cutting collection and cutting position in the crown on rooting quality was evaluated in cuttings taken from seven-year ortets. The evaluation of various dates of cutting collection in spring demonstrated a possibility of successful propagation by cuttings during a relatively long period from full bud dormancy to flushing onset. The relationship between the development of aboveground parts (flushing, shoot and bud formation) and rooting quality was not established. The exposure of cuttings in the crown of parent tree with respect to the cardinal points did not influence rooting percentage and quality. A somewhat higher rooting ability was observed in cuttings from lower parts of the crown in comparison with cuttings taken from the highest whorls. Differences were more perceivable in generally weak-rooting clones. The comparison of rooting quality in cuttings from seven- and eight-year mother plantations with cuttings from a sixteen-year mother plantation confirmed that not only the rooting of cuttings collected from older mother plantations is weaker but also their growth is slower and their plagiotropic growth continues for a longer time.

In 2003 to 2005, Chrysomela populi L. gradated on yearly cut Populus nigra var. italica in street alleys in Brno and elsewhere. Imagoes occurred on trees from the end of April or from the beginning of May. In rearing, the chrysomelid consumed unwillingly leaves of 2-year shoots and laid on average 142 eggs. On leaves of shoots, imagoes damaged 100 to 200 cm² during 5 to 7 weeks, produced 480 to 900 frass pellets and laid on average 506 eggs. Oviposition was continual with breaks amounting to on average 2.6 days. Embryonal development took 6 to 8 (in the laboratory 5) days. Larvae of the 1^st generation occurred from mid-May to mid-July. In the course of 2 weeks (in the laboratory during 10 days) of life, they damaged about 20 cm² leaves and produced about 300 frass pallets. In the laboratory, prepupae took 2 days and pupae 4 days. Imagoes of the 1^st generation occurred from June to September. They damaged on average 113 cm² and produced on average 553 frass pellets and 653 eggs. At a temperature of 24 to 28°C, imagoes damaged on average 84 cm² during 2 to 3 weeks and diapaused until the next year. On growing up leaves, imagoes lived longer showing higher consumption of food and higher fecundity as against new fully-grown leaves. Larvae of the 2^nd generation destroyed on average 2 cm² smaller area than larvae of the 1^st generation. Part or all imagoes of the 2^nd generation diapaused. Imagoes of the 3^rd generation damaged 40 to 70 cm² leaves before departure to wintering grounds. In our natural conditions, the prospective 3^rd generation is always incomplete. Cleonice callida Meig. and Schizonotus sieboldi (Ratz.) rank among important enemies.

Two spring phenophases (bud-burst and leaf unfolding) of a parent stand and naturally regenerated undergrowth of European beech were observed in conditions under different stand density over the last 10 years. The results proved the unequal onset of phenophases of the parent stand individuals in relation to their sociological status. In the case of codominant and dominant trees the delay of 2-5 days was observed in comparison with subdominant trees. The influence of the parent stand structure on the onset of the undergrowth phenophases was also observed. The onset of phenophases differed by 2-20 days among individuals grown under different density of the parent stand. The onset and course of phenophases also differed between the years. The trend of the average onset of leafing in the period 1995-2004 shows a shift to earlier dates by about three days. Temperature summation of average daily temperatures with the base temperature of 8°C, in the framework of the model predicted bud-burst of beech, showed the lowest variability in comparison with other temperatures.

Soon after bark-beetle attack as well as after clear cutting, grown-up mountain Norway spruce forest cast the following mass of needles: 50-60 kg of dry matter per tree, or 18-20 tons per hectare, containing 8,800-10,000 kg/ha of carbon, 190 to 250 kg/ha of nitrogen, 13-16 kg/ha of phosphorus, 65-91 kg/ha of calcium, 9-13 kg/ha of magnesium and 56-67 kg/ha of potassium. These values were obtained by application of equations assessing needle mass from measured tree and plot parameters, and from chemical analyses of two types of needle material (from living and dead trees).

In 2002 a study focused on the evaluation of height and density of expanding natural regeneration of Fraxinus excelsior L. (FE) was carried out on Velká hora Hill, a locality in the Bohemian Karst (Český kras). The examined area is located in Karlštejn National Nature Reserve and takes up around 31 ha. The parent rock is limestone. The expansion depends on soil and exposition conditions and relates to the water balance gradient. FE reached the highest densities (up to 6,000 individuals/400 m²) on Velká hora's peak plateau on medium-deep, heavy-textured decarbonized soils. The lowest expansion (508 individuals/400 m²) was found on slopes fully exposed to south (S) with water retention capacity lower than 20 mm. In total, the average density was 1,190 individuals/400 m². FE natural regeneration reached the highest average heights (around 210 cm) on Fageto-Quercetum illimerosum mesotrophicum, the smallest heights on Carpineto-Aceretum saxatile. Average height in the locality was 47 cm. No relation was found between FE natural regeneration height or density and the distance of a fertile specimen. The distance exceeded 70 m only in 3.4%. FE seeds could be detected almost everywhere at the area. FE is capable to establish itself on any location of the studied locality except ecologically extreme parts of rock steppe without forest and Fagus sylvatica L. stands occupying S slopes. On less favourable sites it is capable to use the protection of other tree species and as a low growing tree it can eventually dominate the site. In more favourable conditions it expands on the whole area, where it can dominate the undergrowth already at 1-m height. If the forest sites are left to natural development, a distinctive change in the tree species composition could take place in a short time period. Such a change could have an essential impact on light conditions, energy flux and species composition of plant and animal communities.

Possibilities are assessed of the natural regeneration of Douglas fir under conditions of Hůrky Training Forest District, Higher Forestry School and Secondary Forestry School in Písek, in stand 12C7, forest type 3K5. The stand is situated at an altitude of 430 m above sea level in an area with mean annual temperature 7.3-7.5°C and mean annual total precipitation 550-575 mm. Under the stand dominated by Douglas fir (65 years of age), natural regeneration of the mean density of 53,800 seedlings/ha appeared due to lateral light coming from the north. The highest density of Douglas fir natural regeneration was noticed under the stand 10-14 m from the stand margin. The light penetrating through the marginal stand wall was found to be of greater effect on the density of natural regeneration than the upper shading caused by the parent stand. With this method of regeneration, Douglas fir is less light-demanding than spruce. Height and height increment of advance regeneration were greater in places with sufficient light near the stand margin. Thus, natural regeneration of Douglas fir is successful there giving conditions for the origin of a new generation of the stand with a sufficient proportion of Douglas fir.

Habitat characteristics of 43 capercaillie (Tetrao urogallus) leks were studied in the mountains of Central Slovakia (West Carpathians) in 1984-2002. Macro-habitat was described with respect to topography and succession stage. Micro-habitat was described with respect to forest type and forest stand structure. Twenty-seven out of forty-three display grounds were situated in the upper half of the lateral ridges. Sixteen leks were located on hills of the lateral ridges (slope < 10%). All the leks were situated in old succession stages of the forest (80-200 years old). Twenty-seven display grounds were located in natural forests, sixteen leks were situated in man-managed stands more than 80 years old. Leks were situated in a variety of forest types with overstorey tree-density between 400-1,050 stems per ha. Distribution of leks was limited above all by macro-habitat characteristics (elevated sites, old stands). Age-space structure seemed to be a significant micro-habitat feature (preference of multi-layered stands).

A study conducted in 1999-2000 in 6 compartments of the Chełmowa Góra forest reserve, situated in the ŚwiętokrzyskieMountains, was aimed at harmful insects infesting cones and seeds of Larix decidua Mill. subsp. polonica (Racib.) Domin. Insect rearing and seed and cone cutting yielded 1,045 specimens of insects belonging to 8 species. Resseliella skuhravyorum Skrzypcz. (Diptera: Cecidomyiidae) and Megastigmus pictus (Förster) (Hymeno-ptera: Torymidae) were the most abundantly represented species. They were present in cone samples of all investigated trees. The index of infestation of cones by insects (WZS) was higher in the case of trees growing at the forest edge. The analysis by cutting showed an insignificant percent increase - 6.7% of sound seeds while 88.9% of seeds were blind. M. pictus damaged 2.6% of larch seeds, while R. skuhravyorum 1.7%. The parasitoid Mesopolobus zetterstedtii (Dalla Tore) was received from the mass rearing where its host is M. pictus.

The article deals with economic aspects of sustainable forest management. The analysis stems from Plíva's typological system. Several hundreds of variants were calculated for forest silviculture profitability classified according to management intensity, target management system, proportion of ameliorating and improving species, proportion of natural regeneration, and set of forest types. The results show a possibility of labour saving and also marked differentiation of the effect of wood production function depending on natural and production conditions and management intensity.

Alder decline along watercourses is one of the marked manifestations of tree decline in the Czech Republic. Local decline of alder trees is documented in the Czech Republic for about 15 years. The aim of this paper is to evaluate causes of alder decline and assess health conditions of other species of riparian stands at 2 localities on the medium reach of the Lužnice River. Effects were studied of abiotic and biotic stressors on the health condition of tree species. No fungal pathogen was found in tissues of declining alders which would be present in all trees and which could be considered to be the main causal agent of the decline. Even an occurrence of the causal agent of alder decline named alder-Phytophthora has not been proved. Tree-ring analyses demonstrated decreasing trends of an increment in alders; however, an abiotic or biotic factor showing direct effects on the fluctuation of tree ring dimensions has not been positively determined. A marked role in the alder decline is demonstrated particularly by abiotic factors accompanied by the secondary activation of some pathogens. Generally, the phenomenon can be named as polyetiologic decline.

In 2001-2005, the effects of game on the condition and development of natural regeneration of a floodplain forest were studied in three permanent transects in the Vrapač National Nature Reserve (NNR). Fraxinus excelsior, Acer pseudoplatanus, Acer campestre and Acer platanoides predominated in the regeneration. The species were markedly damaged by roe deer (Capreolus capreolus) and fallow deer (Dama dama) browsing, the most affected being Acer pseudoplatanus. In spite of always newly occurring trees from self-seeding, the abundance of trees decreased during the studied period, self-seeding did not grow up from a height of 30-40 cm, the proportion of Acer pseudoplatanus decreased and that of Fraxinus excelsior increased. In addition to browsing, in 2003 and 2005 browsing damage to bark was noted in some places and in 2005 also the breaking of trees with subsequent browsing of terminal shoots, the causal agent of both types of damage being fallow deer. The development of natural regeneration is limited in principle by trophic preferences of game and by the tolerance of particular species to repeated damage. On the basis of these conditions it is necessary to consider the present game stock to be contradictory with objectives of area protection and preservation.

The health condition of the population of elms in the region of southern Bohemiawas studied from the viewpoint of their decline, the occurrence of Dutch Elm Disease (DED) and the presence of other diseases. Of the total number of 105 elms in total 33 of them were without any symptoms of the disease or other damage. Elms regenerated quite spontaneously in the neighbourhood of mother trees and their increasing population in mixed forests is hopeful. According to macroscopic symptoms, DED was identified in 10 trees but the presence of pathogens Ophiostoma ulmi and Ophiostoma novo-ulmi was not identified in isolations. A possible reason of this observation is overgrowing the colonies by the Phomopsis oblonga mycelium. This fungus was identified in most isolations. Thus, its role requires further research.

The results of research on the value production of the stands of poplar clones Robusta and I-214 carried out in Slovakia are presented. Models of value yield tables were constructed separately for each clone. The models simulate gross and net financial yield of wood production in dependence on the site index and age of stand. They were constructed on the basis of the models of assortment yield tables, timber prices according to assortments and the models of own costs of timber felling and processing. The clone I-214 produces a faster and higher proportion of thicker assortments of average and below-average quality, and therefore it has the higher value production at a younger age only. Robusta produces smaller diameter but higher quality assortments and has the higher value production only at an older age. The site index of the stand is the most important factor in the value production of poplar clones. Differences in the production between site indexes are much greater than between the clones.

In the locality Hnilé Blatá (the High Tatras Mts.), the structure was measured of root branches in the windthrown spruces (Picea abies [L.] Karst.). After cleaning the root plates, the number, diameter, and length of individual root branches were measured. Individual root branches were classified into twelve diameter classes - according to their diameters measured in the middle of the root branch length. We found out a high frequency of the root branches in the first three root-diameter classes; the values of the average frequency of root branches smoothly declined with their diameters increasing. We found out the lowest mean values of the root branch length in the first two root diameter classes. However, the values of total average length of root branches were the highest in the first root diameter class and these values continually decreased with increasing values of the root branch diameter. On the basis of the high values of root frequency and of total root length in the thinnest root-diameter classes, it seems that the spruce trees growing in gley soil form a similar root structure as those growing in podzolic brown soil.

The aim of this paper is to show the application of pine bark to indicate the level of air contamination by cement-lime dust and to determine the impact range of cement plants. The pine bark was analyzed in the forested formed around three cement plants in the Świętokrzyski administrative district (South of Poland). The test results were compared with the results gained from the controlled forested areas, free from alkali contamination. The strongly alkali areas show high pH_H2O of bark in the range of 7.2-8.5 and low coefficient of change v% = 2.2. The pine bark values of pH_H2O in the alkali areas are on average 2.5 times as high as those achieved in the controlled area (natural pH of bark shows the range of 2.8-3.5). On the basis of the measurements of pH_H2O there are five alkali-forested spheres determined. The existence of the forest spheres confirms the variable mineral composition of the bark, and first of all the variable content of calcium, magnesium, potassium, aluminium, manganese, zinc and iron as a function of the distance from the emitter and real dust fall.

In 2001, galls were analysed of Pemphigus spyrothecae Pass. taken in one- to three-week intervals from Populus nigra and P. nigra var. italica at 4 localities in Brno. Fundatrices matured in the first half of June and during the first half of summer produced about 50 offsprings. Virgines produced about 10 offsprings which grew up in winged sexuparae. The winged individuals started to occur in galls from the beginning of August. In galls with intact development, on average 500 aphids developed. Galls with intact development on P. nigra var. italica reached larger average dimensions and contained at least by 4% more aphids than galls on P. nigra. About 5% of fundatrices died already in the 1st instar and other 3 to 6% in higher instars by the beginning of reproduction. At localities under investigation, 7.5 to 39.0% of galls on P. nigra and 3.9 to 13.7% of galls on P. nigra var. italica were occupied by the fly Leucopis puncticornis Meig. (Chamaemyiidae). About 24.3 to 32.2% of galls on P. nigra and 23.3 to 49.3% of galls on P. nigra var. italica were occupied by the bug Anthocoris minki Dohrn (Anthocoridae). Hover flies Heringia heringi (Zett.) and Pipiza festiva Meig. (Syrphidae) killing aphids in 3.8 to 30.4% of galls on P. nigra and 6.5 to 6.8% of galls on P. nigra var. italica were an important regulator. In August (i.e. at the beginning of the formation of winged sexuparae), the majority of galls opened through primary slit-shaped or oval emergence holes. A part (7.8 to 19.5%) of galls with so far intact development, however, remained closed and all aphids contained in them died. Diseases (particularly mycoses) often participated in the accelerated dying of aphids. The effect of mortality factors on the gall size differentiation was evaluated in details. The galls do not cause any leaf area reduction. In the case of mass outbreak, they decrease decorativeness of poplars in street alleys. In August and September, liquid excrements fall out from the galls (honeydew) polluting the environment in villages and housing estates.

The silver fir was planted under mountain conditions in order to reveal its response to the addition of finely ground rocks (limestone and amphibolite) mixed with soil into the planting holes. The results document that the increments of the plantations fertilised with amphibolite were higher by 25% on average than those of the control plantations while the increments of the plantations treated with dolomitic limestone were lower by 13%. Generally, as concerns both the plantations with the application of ground rocks and the control ones, the development of the fir plantations in 1994-2007 is considered successful. As the damage by climatic stresses has gradually diminished, the number of dead trees has been decreasing and the height increments have been increasing in the last years, therefore a positive development is to be expected also in future.