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The results of a fifteen-year period of investigations conducted on Norway spruce in the upper plateau of the Jizerské hory Mts. were summarised. The objectives were to evaluate the growth performance of an experimental plantation under harsh environmental conditions and assess the effects of amendments as well as the influence of the forest site variability on growth performance and survival of young spruces. The following treatments were distinguished: (1) lower control, (2) limestone and (3) amphibolite treatments on a less exposed slope of the ridge and (4) upper control on a summit of the mountain ridge. Principle characteristics such as mortality rate, height, annual height increment, stem base diameter, crown diameter and nutritional status were summarized and evaluated. Significant differences between treatments were recorded in heights. The trees fertilized with amphibolite were significantly taller than the control ones in thirteen out of the fifteen evaluated years and the applied limestone improved heights in ten years out of the fifteen evaluated years. A positive effect of amphibolite treatment on stem base diameter was proved in three of the four assessed years and was persisting till 2007 (last measurement of this characteristic), the positive effect of limestone was lasting up to 2006. The considerable role of the site variability was apparent from a comparison between the upper and lower control although they were in a very close position to each other, growth increment of the spruces on the ridge was significantly lower. Temporarily lower N concentration was recorded in the fertilized treatments in comparison with their respective control. The concentration of P was low and decreased to the limit of deficiency in all treatments, P seems to be the most limiting macroelement in the area.

In conifers and other plants with long reproductive cycles, transformed embryogenic tissues can serve as a convenient source of plant material for the testing of insecticidal or fungicidal transgene efficiency. In this report, transgenic embryogenic tissue was obtained after the transformation of somatic embryos of Norway spruce (Picea abies (L.) Karst.) by Agrobacterium tumefaciens with the gus-intron chimeric gene. The stable integration of transgenes was confirmed by PCR and Southern hybridization. The transformation was successful only in a suitable embryogenic cell line sensitive to Agrobacterium. Out of the nine embryogenic lines tested only one gave transgenic callus.

We provide fundamental information about the future development of selected climate elements in relation to anticipated threat to forests in the Czech Republic. All analyses were carried out in relation to four elevation zones with specific potential forest vegetation - up to 350 m a.s.l. (oak dominance), 350-600 m a.s.l. (beech dominance), 600-900 m a.s.l. (beech-fir dominance), 900-1,100 m a.s.l. (spruce dominance). We found out that while the projected increase in mean annual air temperature is almost constant over the Czech Republic (+3.25-3.5°C in the distant future), the frequency of heat spells at lower elevations is expected to increase dramatically compared to higher elevations. The precipitation totals during the vegetation season are projected to increase in the near future by up to 10% and to decrease in the distant future by up to 10% over all vegetation zones. In general, drought is presumed to become a key limiting factor at lower elevations, while increased temperature along with the prolonged vegetation season at higher elevations can be beneficial to forest vegetation. Consequently, northward progression of forest tree species and retraction of the species lower distribution range are a generic response pattern. Such impacts are presumed to be accompanied by changes in the distribution and population dynamics of pests and pathogens. Mainly the impacts on two key forest pests, Ips typographus and Lymantria dispar, are discussed.

Our study aimed to determine morphometric data for wild boar (Sus scrofa) in various areas of the Czech Republic and the potential influence of environment on its body measurements. Three localities with varying agricultural systems and overall landscape structure were selected. Hunted boars were measured for height at the withers, body length, ear length, metatarsal length and weight (depending on the circumstances, either dressed with head, without head, or undressed). We also determined the age of the hunted boars according to teeth development. During 2003-2007, a total 654 boars were examined in various age categories. Body development was similar in all areas and without statistically significant differences until the age of 6-7 months. From 8 months, statistically significant differences in body proportions occur across all localities. It is just at that time that carrying capacities change in the selected localities. The results show that morphometric differences among boars of the same age are influenced by external environmental conditions in which the boars live.

The investigation of foliage biomass development including LAI and the growth of spruce and beech stands in the juvenile stage (age 1 to 21 years) represents a special complementary study to long-term research of water balance components on the experimental forest hydrology area Deštné Mountainside. The experiment is located in the Orlické hory Mts. at the altitude of 900 m on a clear-felled area. In 1982 the spruce plantation was established at 1.5 ´ 1.5 m spacing (4,600 plants/ha) and the beech plantation at 1.0 ´ 1.0 m (10,000 plants/ha). According to tending programs applicable to forest stands in the Czech Republic, two improvement fellings were carried out (1995 and 2001) in spruce and none in beech. In 2002, some 1,550 spruce trees/ha (mean height 10.1 m) and 7,440 beech trees/ha (mean height 4.8 m) were recorded. At the end of the first vegetation season in 1982, the dry matter (DM) of foliage in spruce and beech amounted to 35 and 70 kg/ha, respectively. Five years later (1987), these values increased to 770 and 360 kg/ha in spruce and beech, respectively. At a stand age of 21 years, foliage DM was determined to be 11,940 kg/ha for spruce and 3,050 kg/ha for beech. At the same time, the leaf-area index (LAI) was calculated to be 5.55 and 5.94 in spruce and beech, respectively. The method of foliage biomass quantification, based on the determination of foliage DM of mean sample trees and stand density, enabled to acquire complementary data usable in long-term research of the water regime of spruce and beech and simultaneously to provide information on the potential of biomass production and LAI value of both main commercial species in mountain forests of the Czech Republic.

Climate change is expected to influence the distribution and population dynamics of many insect pests, with potential severe impacts on forests. Spruce bark beetle Ips typographus (L.) (Col.: Curculionidae, Scolytinae) is the most important forest insect pest in Europe whose development is strictly regulated by air temperature. Therefore, climate change is anticipated to induce changes in the pest's distribution and development. We used the PHENIPS model to evaluate climate change impacts on the distribution and voltinism of spruce bark beetle in the Czech Republic. Two future time periods - 2025-2050 (near future) and 2075-2100 (distant future) - are addressed. The period 1961-1990 is used as the reference. We found that while a two-generation regime dominated in the Czech Republic in the reference period, significant three-generation regime regions are projected to appear in the near future. In the distant future, the three-generation regime can be expected to occur over all existing coniferous stands in the Czech Republic. The analysis of altitudinal shift of n-generation regime regions indicates noticeable expansion of Ips typographus development to higher elevations, leading for example to disappearance of one-generation regime regions in the distant future. Uncertainties and limitations of the presented findings are discussed as well.

This research deals with productivity and cost of rock disintegration and side casting of materials with the use of a hydraulic hammer mounted on a PC 220 Komatsu crawler excavator, which is used on rocky slopes of Hyrcanian forests of Iran. A continuing time study was applied during the road construction. To estimate the volume of rock disintegration, the average end area equation was used. The increasing cut-slope height decreased productivity. The productivity of hydraulic hammer averaged at 5.5 m³.h^-1 for the mean work volume of 5.07 m³.m^-1. The unit cost of the system was 7.7 €.m^-3. From the economic point of view a new machine with multipurpose system could be recommended for forest road construction operations in rocky areas.

Adapting forests to climate change involves silvicultural measures such as use of a range of species and the fostering of mixed stands. We tested these in a Sitka spruce forest in southern Scotland, employing the Ecological Site Classification to match suitability of 24 species to six climatic and edaphic variables under values of accumulated temperature and moisture deficit projected for a medium emissions scenario for the present century. Both median and 90^th percentile values were contrasted. In the first case there was a small change in species suitability with Sitka spruce, noble fir, downy birch, sycamore and aspen being the most suitable species. When the 90^th percentile values were employed, the suitability of Sitka spruce and similar conifers had declined by the 2050's due to soil moisture deficits. The actual performance of a range of species in a long-term experiment on a similar, warmer site showed several productive conifers including Sitka spruce that maintained reasonable growth when planted in mixture. Mixed plots were developing into pure stands of the most productive species. Species diversification was the most practical adaptation measure for this forest and should concentrate on areas of the greatest risk like south-facing slopes with free-draining soils.

The Lusatian lignite-mining district (Eastern Germany) is characterized by a high share of marginal post-mining areas. At these sites, crop yield is generally low, and hence, conventional land use systems often fail in terms of reliable and efficient crop production. In this paper the attempt is made to evaluate the production of woody biomass for bioenergy in short rotation coppices (SRC) and alley cropping systems (ACS) with black locust (Robinia pseudoacacia L.) and lucerne (Medicago sativa L.) from the aspect of possible ecological and economic benefits compared to the conventional agricultural recultivation practice. The results show that, due to both high establishment and harvesting costs and comparatively low prices of energy wood, land use systems such as SRC or ACS are currently hardly profitable compared to conventional agriculture. However, the cultivation of black locust resulted in a higher humus accumulation and in a lower harvest-related nutrient export than the cultivation of lucerne as a typical recultivation crop in this region. Therefore, it can be concluded that for an improvement of soil fertility woody biomass production is more beneficial than the conventional agricultural recultivation practice.

Assemblages of earthworms were evaluated in spruce and beech stands in the Kienhaida Nature Reserve (Krušné hory Mts., Czech Republic) and its immediate surroundings, where site conditions were modified by the soil preparation for forest regeneration. The beech stands of the reserve showed low diversity but higher earthworm abundance than did the spruce stands, which in turn showed the lowest Lumbricidae abundance (18 individuals.m^-2). The highest abundance of earthworms (124 individuals.m^-2) was found in the soil of mounds created 30 years prior to sampling from the organic soil of the A_h horizon. The highest species diversity and low abundance were characteristic of areas between the mounds, the soil surface of which was greatly disturbed after removal of the A_h horizon to create those mounds. The degree to which the reforested clear-cuts created due to air pollution were overgrown with weeds contributed positively to the diversity and abundance of Lumbricidae.

The seed production area (SPA) is an improved plantation managed for production of quality seeds for a large-scale plantation programme. The soil nutrient is one of several factors affecting seed production among SPAs. The status of soil nutrients and their effect on seed production are poorly understood. Hence, the present study was undertaken in 20 seed production areas located in different seed zones of Karnataka, South India. Results showed that there was a greater variation among SPAs in various soil properties like soil pH, organic carbon, available NPK (nitrogen, phosphorus and potassium). Some of the studied parameters recorded significant variations among three different depths: 0-20 (top), 20-40 (middle) and 40-60 cm (bottom). For instance, organic carbon and available potassium showed significant variations at different depths, where the highest content was recorded in the top layer, followed by middle and bottom layers. Considering associations between soil properties and tree growth, organic carbon was positively associated with dbh (diameter at breast height; r = 0.500), stem roundness (r = 0.351) and stem volume (r = 0.250). Similarly, available nitrogen positively influenced the stem volume (r = 0.250). Though the fruit yield varied among SPAs, none of the studied soil parameters showed a significant influence on fruit yield indicating that some other factors like genetic ones, phenology, rainfall overlapping with peak flowering might control it. Data on site quality showed that all existing SPAs studied were growing in poor site conditions, however, this could be one of the factors affecting overall seed yield among SPAs. Hence, it is recommended to undertake a few important silvicultural interventions like application of fertilizer/organic manure, soil working, spraying of floral hormone and others to improve the existing seed production level.

The objective of this study was to obtain information about changes in cold hardiness of larch and silver fir seedlings during autumn and spring by help of measurements of electrolyte leakage from shoots (SEL) and root system (REL). The values of electrolyte leakage from the untreated (control) root system of silver fir decreased during autumn (from 28% on September 25 to 24% on November 27). Minimum values were reached on March 26. A decrease in electrolyte leakage was found for silver fir shoots (SEL) (the maximum was detected on October 2 - 12% and minimum on November 27 - 7%). Contrary to REL, SEL increased in March. The rate of electrolyte leakage from treated (after artificial frost) roots and shoots decreased during autumn (REL and SEL minimum on November 27). The change in the rate of electrolyte leakage from untreated larch roots was similar to that from silver fir roots during autumn. The values continually decreased from 26% (on September 25) to 12% (on November 27). The course of electrolyte leakage from the treated root system was similar for both species. The differences between electrolyte leakage from larch shoots (treated und untreated ones) were statistically significant, but without any clear tendency during autumn.

The paper summarizes the main characteristics of a mixed stand during 80-year transformation to the mixed stand with permanent selective structure. The initial main stand was mostly composed of conifers with group arrangement, broadleaves as the reserved trees created the upper storey. Partial opening by thinnings prepared the stand for regeneration. Heavy thinning in 1959 (22% of the growing stock) opened the main stand and released the advance growth of broadleaves. Subsequent stand development was negatively affected by air pollution. Mainly fir and spruce responded to air pollution by deteriorated health condition and increment reduction. Beech and other broadleaves gradually increased their proportion in the stand (64% of the growing stock in 2008). Initial diameter distribution was sinistral, reserved trees affected the frequency of thick trees. Final diameter distribution resembled the model curve for selective forests, the number of thin trees was below the model curve for broadleaved forests with selective structure in these types of localities. Mean increments of individual species changed according to their stand position. Low fecundity of trees, weed infestation and game damage limited natural regeneration, artificial regeneration dominated for the whole time. The complicated structure corresponding to selective forest occurred rarely during the monitored period, the stand was differentiated mainly by spatial arrangement.

Coarse woody debris (CWD) is an important structural and functional component in forests in Northern Iran. In this study we determine the temporal patterns of CWD in Kheyroud Forests by examining the CWD volume in different decay classes and size classes along a chronosequence of secondary forest succession. The volume of CWD followed the general "U-shaped" temporal trend: the highest in the late successional forest (51.25 m³.ha^-1), lowest in the middle successional forest (25.95 m³.ha^-1) and intermediate in the early successional forest (37.05 m³.ha^-1). The late successional forest had a larger amount of logs, snags and stumps than the other two forests. In contrast, the snag volume did not differ between the late and middle successional forest. CWD in decay classes III and V was greater in the late successional forest than that in the other two forests, while CWD in decay classes II and I did not differ among the three successional forests. CWD in class II and I was significantly higher in the early successional forest than that in the middle successional forest. In the early and middle successional forests, CWD in early decay class was dominated by Carpinus betulus L. followed by Fagus orientalis Lipsky. In the late successional forest, CWD in early decay class was dominated by Fagus orientalis while CWD in the late decay class was dominated by Carpinus betulus. While forest succession had a large influence on the amount of CWD in different decay classes, it had no effect on CWD distribution among the different size classes. Our results suggest that both anthropogenic and natural disturbances have had a long-term effect on the distribution of CWD among three forests.

This study is focused on substitute European larch stands in the Krušné hory Mts. (northern part of the Czech Republic). Research was conducted within larch thinning experiment Kalek (780 m a.s.l. in the category Piceeto-Fagetum oligo-mesotrophicum - Calamagrostis villosa). Results showed that the aboveground biomass of the investigated substitute unthinned larch stand represented approximately 102 thousand kg of dry matter per ha at the age of 20 years. Stemwood (ca 59%) is the most important part of the aboveground biomass. Needles, live and dead branches accounted approximately for 6%, 17% and 11%, respectively, and stem bark only for 7%. At the age of20 years, the investigated substitute unthinned larch stand accumulated: nitrogen - 307 kg, phosphorus - 21 kg, potassium - 136 kg, calcium - 122 kg, magnesium - 53 kg per hectare. Thinning with consequent removal of aboveground biomass may result in nutrient losses. Especially, the removal of whole tree biomass by thinning for chipping in areas previously degraded by acid deposition may result in calcium and magnesium deficiency because of their low content in forest soil. On the other hand, thinning supported faster growth of trees left after thinning and consequently faster biomass and nutrient accumulation. Our results supported the recommendation that the use of biomass from thinning for chipping should be limited to stemwood only and the remaining aboveground biomass (mainly needles and branches) should be left in the forest ecosystem for decomposition in conditions of the historically disturbed area of the Krušné hory Mts.

Information on the historical background of the present forest conditions is needed for proper decisions on forest management. Disturbances play a major role in the formation of forest structure and composition. This paper compares the present break-up of mountain spruce stands in the Bohemian Forest (in the Šumava Protected Landscape Area) with conditions during their initiation using dendrochronological techniques. On three selected localities we established two study plots within relatively old stands of unknown origin. Stands were recently broken up by a windstorm. The present situation was described by diameter and decay class distribution. To describe the situation at the stand initiation, we cored at least 40 stems on each plot to get the age structure and growth series of trees. Disturbances were marked by discovering synchronous releases on tree-ring series. Main population waves were initiated in association with severe disturbances during a relatively short period, leading to the establishment of relatively even-aged, homogeneously looking stands. The disturbances were synchronized between plots and accounted for by historically known windstorms or bark beetle outbreaks; notwithstanding, logging as a disturbance factor is also particularly possible.

The paper deals with the occurrence, development and harmfulness of imported willow leaf beetle (Plagiodera versicolora Laich.) in riparian and accompanying stands of the Svratka and Svitava rivers in the region of Brno. Salix fragilis L. and S. × rubens Schr. are the most damaged species there. Imagoes leave wintering places usually at the beginning of May. During about a 60-day period, they damage ca. 23.3 cm² leaves of S. fragilis and lay 250 to 730 (on average 539) eggs. The whole egg-laying consists of 16 to 48 (on average 35.5) groups with 6 to 26 (on average 15.2) eggs. The fecundity of females hatched in the laboratory is minimally twice lower. Larvae hatch after 5 to 8 (in the laboratory after 4.3) days and damage about 282 mm² leaves. The development from laying eggs until hatching imagoes of the 1^st generation takes about 21 (in the laboratory about 15) days. Imagoes of the 1^st generation occur on trees from the end of May to mid-August and die after completing their reproduction. Plagiodera versicolora creates 3 to 4 (in the laboratory 4 to 6) generations during a year. The small part of imagoes of the 2^nd generation, predominant part (or all) imagoes of the 3^rd generation and under conditions of a tetravoltine development all imagoes of the 4^th generation enter a diapause. In the course of the growing season, the food consumption of imagoes and larvae decreases and fecundity of females markedly decreases. Schizonotus sieboldi (Ratz.), Medina melania (Meig.) and M. luctuosa (Meig.) rank among main enemies of Plagiodera versicolora.

The influences of long-term flooding and Phytophthora alni subsp. alni infection on the growth and development of 4-year-old Alnus glutinosa (black alder) saplings were investigated. The black alder saplings were divided into four groups and then subjected to combinations of both factors - flooded and inoculated with pathogen, flooded non-inoculated, non-flooded inoculated, and control. The biomass of the living roots and actinorrhizae, increase in stem length, length of leaves, rate of chlorotic foliage, amount of foliage biomass and length of stem necrosis were assessed after seven weeks. Both factors, flooding and P. alni infection significantly affected the black alder. In addition, a significant effect of interaction was observed. The inoculated flooded group had a substantially lower biomass weight of living roots, actinorrhiza and leaves than the other groups. The necroses caused by the pathogen in the flooded group were more extensive than those in the non-flooded one. These findings demonstrate that the simultaneous incidence of stress caused by flooding and P. alni infection is highly dangerous for black alder.

Biotic agents driven spruce decline has been observed over several regions in Europe. We studied the spatial pattern of spruce stands mortality due to biotic agents in three spruce dominated regions in Slovakia - the Kysuce, Orava and Low Tatras regions. Regularly reported data on sanitary felling were used for the analysis. Geostatistical techniques and other spatial modelling tools were used to design the zones of biotic hazard for each region. Zone A stands for the totally disintegrated stands with extremely elevated activity of biotic agents. Zone B represents the buffer zone around the zone A. Its width depends on the spreading potential of biotic agents and related stand mortality observed during the last years. Zone C stands for the background areas, with more or less healthy stands. Zone-specific forest protection measures are proposed. Such a system allows for the priority rating of unnatural spruce stand conversion and optimal allocation of forest protection measures.

Natural mixed beech-fir forests were quite widely replaced by spruce dominated stands in Slovakia. Given the demands on the assessment of the forest status as well as on stopping the biodiversity loss it is required to evaluate the influence of Picea abies (L.) Karst. on the species composition. In a case study from the Veporské vrchy Mts. natural beech dominated forests were compared to stands with different spruce proportion. Within three groups of relevés with no, less and more than a half proportion of Picea abies the species diversity and Ellenberg indicator values were compared. The response of particular species to the proportion of Picea abies was evaluated by partial relation in direct gradient analysis. The increasing spruce proportion causes particularly higher occurrence of acidophytes and a decrease in nitrophytes. Species with the highest positive response to spruce are mostly shallow-rooted or characteristic of natural spruce forests. Greater richness along with the highest diversity was found in mixed stands with less than a half proportion of Picea abies. The most significant difference in species composition was between natural and spruce dominated stands. However the proportion of Picea abies does not reduce the species diversity in general, it causes significant changes in the species composition. As the results show, to avoid the negative effect and loss of phytodiversity it is required not to grow spruce dominated stands out of the natural occurrence of Picea abies.

The diversity of arbuscular mycorrhizal (AM) fungi of Acacia catechu Willd. was studied. Dominant AM spores, the bacterium Rhizobium sp. along with the fungus Trichoderma viride were isolated from the rhizosphere of A. catechu and mass-produced in laboratory. The co-inoculation effect of Glomus mosseae, Glomus fasciculatum, mixed AM (Glomus spp. [except G. mosseae, G. fasciculatum] with Acaulospora spp., Sclerocystis spp. and Gigaspora spp.), Rhizobium sp. and Trichoderma viride was studied as exerted on the growth of A. catechu seedlings. All inoculated seedlings showed improved seedling growth compared to the control. Inoculated seedlings had a pronounced effect on all growth parameters such as height, fresh and dry weight of roots and shoots, AM spore count, per cent mycorrhizal colonization in roots and root nodule number in comparison with uninoculated seedlings. Phosphorus uptake was also higher in inoculated seedlings than in the control. This study provides a good scope for commercially utilizing the efficient strains of AM fungi for beneficial effects with other beneficial rhizosphere microflora in the primary establishment of slow growing seedlings ensuring better survival and improved growth.

Small mammals cause serious damage to forests but there is only little knowledge of their ecology and possibilities of plantation protection. The objective of our study was to collect information on the damage caused by rodents to plantations of forest tree species. Data were obtained from a survey conducted in 2008 that was aimed at damage caused by small mammals. Questionnaires were sent mostly to foresters engaged in the Lesy CR state enterprise. We obtained usable data from 316 foresters. The response rate was 81%. It was confirmed that rodents cause significant damage all over the Czech Republic and that the occurrence of damage cannot be easily predicted with certainty as significant damage may appear perhaps in a small part of the threatened plantations where the key conditions for small mammals have been fulfilled. The main factors which affected probability of damage include: presence of a woody species attractive to rodents; suitable structure of ground vegetation enabling the pest species to breed sufficiently during the vegetation period; and also long-lasting snow cover. The current approach of forestry practice to damage by small mammals is considerably passive and we are missing an alert system of threat to stands and a methodology of dealing with problematic situations. Most of the foresters are uninterested in small mammals and many have only very smattering knowledge of the dangerousness of individual species and their ecological requirements. The use of rodenticides is expensive and the most effective and economic measure to lower damage by small mammals is to support forest management favouring natural regeneration of forest stands.

Unit hydrograph is a basic method to show changes in runoff in the watershed. The investigation of runoff changes was carried out in the U Dvou louček watershed situated at the summit part of the Orlické hory Mts., East Bohemia. The waveform ordinates of recession limbs of unit hydrographs obtained using a common approach had to be approximated by the least-squares method. Final hydrographs reflected both drainage treatment and forest stand growth influencing the runoff from the watershed. Both factors increase culmination in synergy and reduce runoff on the recession limb of the hydrograph. We confirmed increased maximum runoff taking up 25-30% of the total runoff time when waterlogged sites were drained. The culmination increased by 0.2-0.8 mm/hour indicates the runoff increased by 2-8 m³/ha/hr.

The aim of this study was to compare the degree of root rot damage in two large complexes of Norway spruce stands established on former agricultural land at fertile sites. The root rot infection was observed on the stump cutting area on both intended and salvage clear fellings. Stands in Kružberk area in the Nízký Jeseník Mts. established on arable land showed very poor stability and large root rot damage at the age of 40-50 years. In contrast, stands in Lužná area in the Javorníky Mts., founded on former sheep pastures, were markedly much less damaged at the age of 90-110 years and proved to be able to provide quality timber, although they were damaged by the root rot as well.

The main task of the study was to investigate the growth conditions of silver fir natural regeneration in the Karkonosze Mts. (Poland). The paper examines the quantity and quality of light reaching the forest floor in stands of different canopies. The aim of the study was also to define the optimal site conditions for silver fir planting under stand canopy. Data on the natural regeneration and stand structure of each investigated stand were collected on circular plots in a grid of 15 × 15 m in 1999 and 2000. Biometric measurements of fir plants planted under various stand canopies were done three times (May 1999, autumn 2000 and 2001). It was found that the fir was not a dominant tree in all size classes from seedlings to saplings. Seedlings (both phases) of spruce, beech, sycamore and rowan occurred in all studied stands. The optimal conditions for fir development were found under larch canopy. That was demonstrated by the highest increment of height, diameter and offshoots. The worst conditions for fir growth were under beech and spruce canopy, which was indicated by the lowest diameter and height. The highest PAR was recorded under pine canopy, whereas the lowest one under beech canopy. Beech stand induced a lower R:FR ratio than the other tree species both on sunny and cloudy days. The highest R:FR ratio was found under the canopy of larch and pine stands.

A young speckled alder (Alnus incana [L.] Moench) stand was planted on a tract clear-felled due to air pollution and located on a summit plateau of the Jizerské hory Mts. (Central Europe, Czech Republic) at an altitude of 950 m a.s.l. The aim of the experiment was to test the suitability of Alnus incana to form preparatory stands covering the site and thus enabling the reintroduction of more sensitive target species. A potential of Alnus incana to respond to slow-release fertilizing was tested as well. The control treatment showed sufficient growth dynamics, nevertheless, the fertilization significantly promoted the growth (documented by height, height increment and stem-base diameter). If some limitations of alder such as high light requirements are respected, the speckled alder can be recommended as a suitable species for preparatory stands even in the 7^th and 8^th altitudinal (vegetation) zones, especially when fertilized.

Comprehensive analyses of soil properties of sites of native Scandinavian broadleaved tree species were performed in 36 habitats in East Norway. The material consisted of stands of silver birch (Betula pendula Roth.), white birch (Betula pubescens Ehrh.), black alder (Alnus glutinosa Gaertn.), speckled alder (Alnus incana Moench.), European ash (Fraxinus excelsior L.), pedunculate oak (Quercus robur L.) and sessile oak (Quercus petraea [Matt.] Liebl.). The main objective was to describe the vertical characteristics and variations in some selected soil variables of the soil profiles. Particular soil horizons of 15 Brunisolic soils, 11 Regosolic soils, 6 Gleysolic and 4 Podzolic were sampled and analyzed for soil texture, bulk density, specific density, porosity, oxidizable carbon, total nitrogen content, pH in water, exchangeable acidity, exchangeable cations and anions (Mg, Ca, Mn, Al, S, Fe, B, P and K), cation exchange capacity and base saturation. No regular patterns were found in selected soil properties when tested between various soil units in silver birch stands. Furthermore, silver birch stands were found on sites, which topsoil (i) significantly differed in their cation exchange capacities, (ii) did not differ significantly in their pH values, and (iii) mostly differed in their clay contents and (iv) mostly did not differ in BS. Differences among the Humic Regosols, Luvic Gleysols, Sombric Brunisols, Eutric Brunisols and Humo-Ferric Podzols for silver birch stands in their topmost horizons of humified organic matter intimately mixed with the mineral fraction horizons and differences among particular soil horizons for the main soil properties under all the selected broadleaved tree species stands are discussed.

The paper shows difficulties in the evaluation of the forest status when considering forests with different height structure (uneven-aged forests). It is the main problem in categorizing such forests. Concerning the actual forest management conception in Slovakia, it is assumed that the area of forests with close-to-nature management system will increase. It leads to more structured forests, as for the tree species, age, height, as well as the spatial structure. The typical vertically homogeneous forests account for only 50% of all Slovak forests, according to results from the National Forest Inventory in Slovakia (NFI SR). During the processing of NFI data the stands were divided into 2 classes as follows: (i) vertically homogeneous stands, which are classified into nine growth stages; (ii) vertically heterogeneous stands, which are classified into two growth stages (lower and advanced), and stands in the process of regeneration. New approaches are not based on the visual subjective estimation of forest homogeneity, but on objective analyses of measured values from inventory plots (tree heights, diameters, and age). The paper shows a new approach to the classification of forest stands on an example of the variability of measured heights on inventory plots from NFI.

The incidence of the summer (late-seasonal) growth of shoots was monitored following the planting of Scots pine from different provenances of the Czech Republic and different planting regimes in an experimental plot in Týniště nad Orlicí. In the third year after reforestation the local populations had the highest proportion of summer growth of the shoots (18%) compared to other populations. From the second to the fourth year after planting the percentage proportion of summer shoots was determined for the species Scots pine in conditions of the Polabí region, it was 13.5% of the individuals in each year. The analysis of stem sections demonstrated double rings as a result of the cambium activation through the growth of summer shoots.

The aims of this study were: 1. to determine the effect of dexiccation treatment on the physiological quality of Norway spruce (Picea abies [L.] Karst.) seedlings by measurements of electrolyte leakage from the root system; b) to test the use of hydrogl STOCKOSORB^® for protection of the root system of spruce seedlings during their transplanting. The results showed that desiccation treatment significantly affected the rate of electrolyte leakage (34% leakage for control seedlings and 53% in contrast with seedlings after 5 hours of desiccation). Likewise, significant differences were found in height and root collar increments after the first vegetation period that decreased with the duration of desiccation treatment. The values of electrolyte leakage also increased with the duration of desiccation treatment for seedlings treated with hydrogel. On the other hand, the rate of electrolyte leakage was lower after 5 hours of stress factor than in untreated seedlings. The height and root collar increments were higher in seedlings treated with hydrogel for all variants. The obtained results showed a possibility of using the measurement of electrolyte leakage from the root system to determine the physiological quality of Norway spruce seedlings. The rate of electrolyte leakage over 40% signals the physiological damage to the root system of spruce seedlings. Next, the results confirmed the need of protection of seedling roots during handling. The seedlings without hydrogel had 35% height and 26% root collar diameter increment after two-hour desiccation stress. On the other hand, the same seedlings with STOCKOSORB had 42% height and 48% root collar increment.