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Tree growth is one of the main variables needed for forest management planning. The use of simple models containing traditional equations to describe tree growth is common. However, equations that incorporate different factors (e.g. site quality of the stands, crown classes of the trees, silvicultural treatments) may improve their accuracy in a wide range of stand conditions. The aim of this work was to compare the accuracy of tree diameter growth models using (i) a family of simple equations adjusted by stand site quality and crown class of trees, and (ii) a unique global equation including stand and individual tree variables. Samplings were conducted in 136 natural even-aged Nothofagus antarctica (Forster f.) Oersted stands in Southern Patagonia (Argentina) covering age (20-200 years), crown class and site quality gradients. The following diameter growth models were fitted: 16 simple equations using two independent variables (age and one equation for each stand site quality or crown class) based on Richards model, plus a unique global equation using three independent variables (age, stand site quality and crown class). Simple equations showed higher variability in their accuracy, explained between 54% and 92% of the data variation. The global model presented similar accuracy like the better equations of the simple growth models. The unification of the simple growth models into a unique global equation did not greatly improve the accuracy of estimations, but positively influenced the biological response of the model. Another advantage of the global equation is the simple use under a wide range of natural stand conditions. The proposed global model allows to explain the tree growth of N. antarctica trees along the natural studied gradients.

Quantitative relationships between stand indices and carbon dioxide (CO₂) stocking are missing in the evergreen broadleaved forests (EBLFs) in eastern China and this hinders to estimate carbon (C) budget in the subtropical region. We determined the vegetation-soil C pool and CO₂ stocking using stand indices [diameter at breast height (DBH), total height (H) and wood density] in Schima superba dominated EBLFs in the Tiantong National Forest Park in eastern China. Vegetation biomass was determined by a non-destructive method using the tree volume and wood density approach while soil C concentration was determined using the oil bath-K₂CrO₇ titration method. Finally, multiple regression and one-way ANOVA with LSD test were used for data analysis. Results showed that total C stocks in the vegetation and the 0-20 cm surface soil were 90.53 t.ha^-1 and 116.24 t.ha^-1, respectively. The study revealed that the total amount of CO₂ stocks in the studied forest is 331.87 t.ha^-1. One-way ANOVA with LSD test showed that CO₂ stocks varied significantly (P < 0.05) between the tree growth stages. There was a significant variation in CO₂ stocking capacity within sapling and pole growth stages but no significant variation within standard stage. The stepwise multiple regression analysis showed that DBH, BA and H were related to the C stocking while wood density had no significant effect. The significant amount of C stocking in EBLFs in the Tiantong National Forest Park of eastern China showed the potential and significant C stocks by trees. As the C pool structure changes due to a change in the forest type and location, therefore this study is important to estimate C stocks and predict CO₂ stocks from stand indices in EBLFs which serve as a scientific basis for sustainable forestry operations, rational utilization of forest resources and global warming reduction in EBLFs in subtropical regions of China.

Several different fungi can cause tar leaf spot diseases in maple trees, including three fungi of the genus Rhytisma. Rhytisma acerinum (Pers.) Fries is an ascomycete that forms black stromata known as tar spot on the adaxial surface of the leaves of Acer species. The tar spot (R. acerinum) disease has been increasing in incidence and severity in maples of Hyrcanian forests, northern Iran, in recent years. One of the best ways to manage infestations by R. acerinum is through adequate biotechnical techniques. The isolation of fungal spore colonies was evaluated using different dosages of Oxywet 10% (50, 100, 200, 500 µl), Gentamicin 5% (100, 200, 400; 1,000 µl), and Amoxicillin antibiotics 20% (25, 50, 100, 250 µl) in 100 ml of distilled water in each treatment. All possible combinations of single doses were applied using light and dark treatments. In light conditions, it appears that the Oxywet (200 µl) had the significant effect on controlling R. acerinum. Reduced fungal growth, coefficient and inhibition of fungal growth were observed in the light treatment. The other antibiotics (Gentamicin, Amoxicillin) were not so effective in controlling this pathogen. Results of spore germination showed a significant difference between all treatments. All treatments were tested in pure cultures in the laboratory only. The results obtained cannot be expected of the same effectiveness in open field trials.

Cockchafers are among the most dreaded insect pests in many European countries, causing economic losses in agriculture, horticulture and forestry. In forests of south-western Germany, populations of the forest cockchafer (Melolontha hippocastani) and also the field cockchafer (M. melolontha) have been increasing during the past three decades and, therefore, monitoring of these populations has been intensified. In the present field study, data on adult emergence from the soil, male swarming flights and female oogenesis, collected at three infestation sites by visual inspection, with soil eclectors and with light traps in early spring 2009-2011, are presented and discussed in the context of the current knowledge of cockchafer biology. Furthermore, three air temperature sum models for the prediction of the onset of the swarming flight period in spring, published in the early/mid 20^th century, were validated in view of their applicability in forestry practice.

Sustainability reporting is constantly paid attention by companies for its economic, environmental and social benefits. It supports making use of the wide potential for further development of enterprises and society. Individual sectors use types of indicators that correspond to their specifics. It is also the case of the forestry sector, which is especially characterized by a number of non-market outputs. However, we can find also other specific indicators that are relevant to forest management. The paper proposes indicators for sustainability reporting, which are not part of usual methodologies. These indicators will contribute not only to the formal preparation of sustainability reporting, but so that its benefits would be of significant influence on the development of forest enterprises and the forestry sector using its potential in all areas.

The study deals with differences in the growth of 2-year mix of poplar clones MAX 4, MAX 5 in the first rotation period at a site with the average moisture regime and at a neighbouring site affected by waterlogging. Average diameter at breast height (DBH) at the site without the observable water influence was 19.6 mm (average height 380 cm). Average DBH at the water-affected site was 8.1 mm (height 220 cm). The difference was statistically significant, which corroborates the hypothesis of the adverse influence of waterlogging on the growth of poplar clones. Furthermore, moisture content was ascertained in wood samples. A comparison was made of samples from the butt, middle part and top part of the stem. Differences between the respective stem parts were not statistically significant. Total average wood moisture content at the time of harvest (January 2012) was 59.7%.

The paper summarizes results from the analyses of Norway spruce (Picea abies [L.] Karst.) stands managed by the Forest Administration in Horní Maršov, Krkonoše National Park (KRNAP), which are affected by decline and by yellowing of the assimilatory apparatus. Forest stands included in the analyses were aged 10-80 years and originated from both artificial and natural regeneration. Analyses of root systems were combined with analyses of soil chemical properties and assimilatory organs, weather conditions and emissions. The analyses showed that affected trees had small and malformed anchoring root systems with a lower number of horizontal roots and a lower number of fine roots of lower vitality (high proportion of dead fine roots), which penetrated only through the uppermost humus horizons. Root systems of affected trees are infested by the honey fungus (Armillaria sp.), which colonizes anchor roots. Neither root nor bole rots were detected so far.

In this research the spruce plywood board and combined spruce-beech plywood board were prepared in laboratory conditions using two levels of processing pressure. The bending properties in perpendicular and longitudinal direction were measured and compressibility and density were specified. Considering the obtained results, there was found an overall increase of the bending properties in spruce plywood manufactured by the higher pressure and a decline of properties perpendicular to the grain in combined spruce-beech plywood board. On the other hand, combined spruce-beech plywood boards produced by the common processing pressure performed better than both types of spruce plywood.

Forest roads are the most important ways of access; nevertheless, they are the main source of sediment production. The delivered sediment by forest roads causes environmental problems and pollution of water resources. This study has been done to present a model for estimating the sediment yield of forest road using a multiple regression analysis on the Caspian southern coasts (north of Iran, Lomir watershed). For this purpose, 45 wood dams were created and their sediment volume (dependent variable) was measured. The following independent variables were estimated: road length, road width, road slope, vegetation cover, height of cut slope and road age. Then, a regression analysis was done using SPSS software to present a linear model. In the next step, the accuracy and capability of the presented model were considered and validated using the model for estimating the wood dam sediment. The results showed that road length and road width have significant effects in sediment generation. Also, the presented model can estimate the forest road sediment in northern Iran.

Climate change, air pollution and global challenges. Understanding and perspectives from forest research R. Matyssek, N. Clarke, P. Cudlin, T.N. Mikkelsen, J.P. Tuovinen, G. Wieser, E. Paoletti Developments in Environmental Science 13. Elsevier Ltd., Oxford, 2013 622 pages, ISBN 978-0-08-098349-3. € 142.31.

The work presents the results of phenological observations of flowering and fruit ripeness of the European hazel (Corylus avellana L.) in Slovakia in two time periods: 1964-1983, and 1994-2013. The phenological stations at elevations from 100 to 875 m a.s.l. were grouped to 7 elevation zones, each 100 m wide. In the first studied period, flowering started on 19 March on average, while in the second period it started 5 days earlier. The average duration of flowering equal to 7-9 days did not depend on the elevation, but on the air temperature and weather patterns in the different elevation zones. During the first period, the average elevation gradient of flowering was 5.6 days per 100 elevation meters, while in the second period it was reduced to 3.5 days in the entire elevation profile. In the elevation zones between 300 and 500 m, a high correlation (P < 0.01) between the onset of flowering and elevation was reduced to a moderate level of correlation due to changing environmental conditions. In 1994-2013, the ripeness of hazel nuts started on average on 30 August in Slovakia, showed low variability and moderate correlation with elevation. The phenological elevation gradient was 2.9 days per 100 m of elevation.

With the advantage of Structure from Motion technique, we reconstructed three-dimensional structures from two-dimensional image sequences in a circular plot with a radius of 6 m. The main objective of this research was to clarify the potential of using a low cost hand-held camera for evaluation of the stem accuracy reconstruction, through the comparison of data from two different point clouds. The first cloud comprises data collected with a digital camera that are compared with those collected by direct measurement of the FARO^® Focus3D S120 laser scanner. Photos were taken in a circular plot of pine trees using the stop-and-go method. We estimated the Euclidean distance for corresponding points for both clouds and we found out that most of the points with error less than 11 cm are concentrated mainly on the ground. Regression analysis showed a significant relationship between height above ground and error, the error is more pronounced for points located higher on the stems. As expected, no dependence was found between the error of the points and the diameter at breast height of their respective stems.

We calculated high-power forwarder productivity in regeneration felling with the objective to set long-term work plans. Based on the time studies of the forwarder operator's work operation the operation time consumption was calculated and operation standards for the studied type of forwarder were designed. The standard values were determined based on the volume weight of harvested timber and the forwarding distance. The resulting time consumption required for forwarding 1 m³ of timber, whose mean tree volume is 0.30-0.99 m³.stem^-1, and upon forwarding distance of 100-1,000 m ranges from 0.05-0.09 Nh.m^-3.

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.

Wild boar is a native species in the fauna of the Czech Republic. It is becoming a problematic game species both in the Czech Republic and in other European countries due to its harmful impacts. So far no suitable method of its sustainable management has been devised. Yet, a correct abundance estimate is essential for proper management, field crop damage prevention and proper hunting planning. This paper employed faecal pellet group count to estimate the wild boar density in a forest environment. The research was conducted in a study area covering 12.83 km², which is surrounded by farmland. The count was done under ideal conditions in early spring, after snow had melted. The study area was organised into several differing environments in which different dung densities were expected. The presence of feeding sites, where wild boars concentrated, was taken into account. The conducted count confirmed differences in the utilization of different habitats within the study area. The resulting wild boar abundance was estimated at 64.3 (± 8.9; 95% CI) indd.km^-2.

Anew approach to forestry that increasingly values non-timber forest functions brings new interest and value also to coppice forests. A case study in the Voskop nature reserve located in the Český kras Protected Landscape Area was focused on a comparison of the timber production of individually growing trees and in multistemmed trees resprouting after cutting (stools). We recorded tree ecological characteristics of trees such as existence of stem cavities, whether the tree grows individually or from a stool and whether or not the tree is broken, dead or has a dying crown. In total 2,670 trees were sampled on a 1,875 ha sample plot. The main tree species forming coppice stands are Quercus petraea and Carpinus betulus. The total stock volume of only 136 m³.ha^-1 is very low at 84 years of age. The stock volume of individually growing trees is 84 m³.ha^-1 and the stock volume of trees in stools is only 52 m³.ha^-1 although the number of individually growing trees is lower.

In northwestern Algeria, the production of Aleppo pine (Pinus halepensis Mill.) seedlings in four nurseries is hindered by the damping-off disease. Results obtained indicated that Fusarium spp. are commonly found on diseased seedlings, in most containers and bare-root nurseries. Twenty-one isolates of Fusarium, belonging to seven species, were previously isolated from diseased seedlings, and identified based on their morphological and molecular characteristics and their sequences had been deposited in NCBI-Genbank. These isolates were tested for their pathogenicity to local Aleppo pine seeds. The highest inhibition was observed with F. redolens and F. solani, with 75 and 69.3%, respectively. The root growth inhibition of the Aleppo pine seedlings was significantly different for each isolate. The influence of various isolates of Fusarium spp. on seed germination, shoot and root length and vigour index was significantly different. The disease incidence caused by F. redolens and F. solani was 91 and 90%, respectively.

The paper describes the root system architecture of the forest tree species Fagus sylvatica L., Quercus robur L., Pinus sylvestris L., Carpinus betulus L., Acer platanoides L., and Alnus glutinosa (L.) Gaertn. at the age of 80-220 years growing on the slopes of the Krušné hory Mts. at the altitude of 330 to 480 m above sea level. These species were influenced by open-pit mining of brown coal as well as by power engineeting. The investigation also involves the determination of soil properties of Ranker Cambisols.

Dothistroma needle blight caused by Mycosphaerella pini E. Rostrup was observed for the first time in the Czech Republic on an imported Pinus nigra Arnold in 1999. In 2000, it was also found in the open planting. During three years, it became an important pathogen of pines in the Czech Republic. Its occurrence was noticed in more than 50 localities, above all in the region of Moravia and Silesia and eastern Bohemia. In total, it was found on 10 species of pine (P. nigra Arnold, P. banksiana Lamb., P. contorta Loudon, P. mugo Turra, P. leucodermis Ant., P. sylvestris L., P. cembra L., P. aristata Engelm., P. ponderosa P. et C. Lawson and P. jeffreyi Grev. et Balf.). Also Picea pungens Engelm. was noticed as a host species. In the Czech Republic, Pinus nigra is the most frequent host species of M. pini (80% localities) followed by Pinus mugo (27% localities). On Scots pine P. sylvestris, M. pini was noticed at two localities. The critical period for infection is in the Czech Republic from the second half of May until the end of June. The incubation period lasts about 2-4 months depending on climatic conditions. The first symptoms on the needles infected in the current year appear in August being clearly expressed from September to November.In the CR, Dothistroma needle blight spread probably with infected planting stock obtained from import at the end of the 80s and at the beginning of the 90s.

The effect of ethephon (80, 100 and 120 mg.l^-1) and gibberellic acid (GA₃) (40, 300 and 1,000 mg.l^-1) on the germination capacity (GC) and mean germination time (MGT) of European beech (Fagus sylvatica [L.]) dormant beechnuts or beechnuts pre-chilled for four weeks was determined. Compared to the control (dormant untreated seeds) or beechnuts treated with tap water no significant increase in mean GC was detected after the application of ethephon or GA₃ to dormant seeds. Conversely, both ethephon and GA₃ treatments reduced (ethephon significantly) GC when applied to beechnuts chilled for four weeks prior to treatment. The effect of the treatments on germination speed (MGT) and dormancy release significantly improved when beechnuts were chilled for four weeks prior to the application of ethephon or GA₃. However, the effect of GA₃ on MGT of chilled beechnuts was not so distinct compared to dormant untreated seeds. Reduction in MGT was most obvious in seeds hydrated with 1,000 mg.l^-1 GA₃ prior to germination. Their cold requirement time was reduced by three weeks compared to beechnuts hydrated in tap water.

Only two cambioxylophagous species (Ips amitinus and Pityogenes chalcographus) were found on sections of Picea pungens and Picea abies that belong to economically important pests of Norway spruce. Representatives of the Isarthron sp. (Cerambycidae) were developed on the examined sections of both P. abies and P. pungens. The monitoring of attractiveness of the spruce species P. pungens and P. abies to cambioxylophages revealed that P. pungens was more intensively attacked by I. amitinus while P. chalcographus was more abundant on P. abies. Both bark beetle species preferred shaded parts of tree trunks, although their development was more successful on the sun-exposed side. On P. pungens, abundance of P. chalcographus decreased and abundance of I. amitinus increased with increasing trunk volume. Blue spruce was more attractive to Isarthron sp. compared to Norway spruce.

We summarized development and dynamics of natural regeneration in mountain spruce forests in areas affected by bark beetle gradation in the Šumava National Park. Detailed measurements of the regeneration were carried out using Field-Map technology (www.fieldmap.com) on ten permanent research plots. Research plots included the forests with decaying tree layer, stands in partial decline and stands with a generally healthy, or only partially damaged tree layer. Differences in rates of regeneration are very significant between the particular types of plots, especially in the youngest age class. Differences are also evident in the seedling height under varying treatments. The highest numbers of recruits (9,880 per ha) were found under intact overstorey canopies, while the fastest height growth occurred on clearcuts. This study also investigated and evaluated artificial regeneration done in the past.

Litterfall, an important component of the nutrient cycle in forest ecosystems, was measured for 9 years in young oak stands on two localities classified as beech-oak climax (Fageto-Quercetum). We estimated that about 4 Mg of dry mass per hectare fell each year. Nutrient content in the litterfall represents annually per hectare approximately 40-55 kg of nitrogen, 2-3 kg of phosphorus, 7-16 kg of potassium, 41-73 kg of calcium and 6-7 kg of magnesium. The amount of litterfall is positively correlated with stand basal area and with the death of suppressed tress with small crowns. We found a positive correlation between annual litterfall and the sum of precipitation and a negative correlation between annual litterfall and temperature in summer.

As the climate continues to change, gaps in our understanding of how the altered environment will affect forest hosts and their pathogens widen. In some areas pathogens thought to be present for centuries are changing their behaviour. Dothistroma needle blight caused by the fungus Dothistroma septosporum in northwest British Columbia (BC), Canada, is a good example. In this area both the pathogen and the host, lodgepole pine (Pinus contorta var. latifolia), are considered native species, but here Dothistroma has been responsible for killing mature host trees, which is unprecedented. A plausible link between warmer, wetter summers and directional climate change has been suggested as the primary driver. Those environmental conditions appear to be affecting the host/pathogen relationship for other diseases in the neighbouring central interior of BC including comandra blister rust (Cronartium comandrae). Disrupted host/pathogen relationships tend to favour the short-lived more adaptable pathogens rather than their long-lived hosts. These changes in forest health have not been well accounted for in fields of forest science that have been built on stability and predictability.

The field study in a mountain forest at Bílý Kříž provides a comparison of element fluxes for two adjacent forest spruce stands of the same age (29 years in 2005) but with different stem densities. During five years (2001-2005), bulk and throughfall precipitation was sampled and analysed. Total deposition, dry deposition and canopy exchange fluxes were evaluated on the basis of the Canopy Budget Model. Highly significant differences in base cations, dissolved organic carbon, SO₄^2-, F^-, and Cl^- throughfall concentrations were found between the sparser and denser spruce stands. Throughfall, dry deposition and canopy exchange fluxes were also influenced by stand density. Annual throughfall fluxes of inorganic nitrogen were within 11.9-17.8 kg N.ha^-1.yr^-1 on the sparser plot and within 15.4-20.6 kg N.ha^-1.yr^-1 on the denser plot; annual throughfall fluxes of sulphur were within 15.3-20.3 kg S.ha^-1.yr^-1 on the sparser plot and within 20.7-27.7 kg S.ha^-1.yr^-1on the denser plot. The critical load for nitrogen (11.2 kg N.ha^-1.yr^-1) was exceeded on both plots in all evaluated years 2002-2005. Total annual inorganic nitrogen deposition was higher by up to 37.5% (in 2002) on the denser plot than on the sparser one.

Current British Columbia forest regulations drive the regeneration management towards pure conifer stands rather than remaining in a mixed-species condition. This approach may result in unnecessary vegetation control. The main objective of this investigation was to study the impact of variable paper birch densities on white spruce growth in 15-20 years old stands for management implications. Regression analysis was used to examine the effect of birch density and two competition indices to predict spruce growth. A mixed model ANOVA showed that spruce mean annual DBH and basal area increment differed significantly among sites and density. From the regression analysis it appears that birch density up to 4,000 stems.ha^-1 had no significant influence on spruce growth which is much higher than the current BC reforestation guideline (1,000 stems.ha^-1 broadleaves). Similarly, birch relative density index (RDI) had to exceed 3 to affect spruce DBH growth significantly on all sites except one. On most sites, spruce had a larger DBH than birch. Our results also suggest that rather than following the current broadcast approach to vegetation management, a targeted approach could enhance forest productivity and stand diversity.

The paper addresses the problem of estimating future stand development in heterogeneously structured forests in Sweden; specifically, multi-layered spruce stands and mature pine stands with advanced spruce undergrowth. We first introduce various supporting concepts and models with their empirical databases, model validation and constraints. Secondly, Swedish single-tree growth functions designed for more heterogeneously structured forest are tested using data from inventory plots, a thinning experiment in an uneven-aged forest stand, and yield plots in pristine forest. Future growth of a managed, multi-layered forest was simulated and is compared with other selected functions. Simulation results, expected errors and time constraints are discussed. For most models, projected stand basal area growth deviated 10-20% from the observed growth in individual stands. In single stands, the deviation ranged from 0 to 60%. Validation periods were often 5-15 years, sometimes even more than 30 years. For Swedish single-tree basal area growth functions, on average, a 5% overestimate was found for heterogeneously structured forest across Sweden. Observed growth in a boreal single-tree selection forest was underestimated by 12.5% fifteen years after thinning from above.

Open habitats in closed forests are formed by various biotic and abiotic factors. These new habitats differ from their former parent stands in light conditions and vegetation structure facilitating their colonisation by heliophilous insects. We studied interseasonal differences (2010 and 2011) in the Orthoptera assemblages on eight clearcuts in beech forests. Using a sweeping method, altogether 20 species were recorded on the clearcuts in the first year, 26 in the second. In the second year, species number and abundance were higher in all orthopterans and also in the suborder of grasshoppers (Caelifera). In the crickets (Ensifera), interseasonal differences in the species number and abundance were not significant. The species composition differed among the plots also within individual years. In the second year, the frequency increased in 22 species (84.6%) while it decreased in four. We suggest that the ground-dwelling Caelifera species are better bioindicators of the deforested plot colonisation than the arbusticolous Ensifera.

With increasing mechanization of forest harvesting operations the impacts on soil have increased quite dramatically. The objective of this paper was to examine the relationship of slope and soil loss. This research was carried out in parcels 14 and 26 of the third district of Nav-Asalem forest in the north of Iran. Erosion plots were 75, 150 and 225 m² with two slope classes. After each rainfall event the amount of runoff was measured; then, a sample was taken to determine the weight of soil loss. The results of correlation analysis by Pearson's test between soil loss and slope classes, soil loss and slope length showed that there was a significant (P < 0.05) and positive correlation between the mentioned factors. Also, linear regression between soil loss, slope length and slope gradient was significant. It could be concluded that studying and underlying factors that increase soil loss such as soil type, rainfall intensity, should also be taken into consideration in future. Skid trail construction and skidding should be limited to the slope of < 20%; machine traffic should be restricted. The above-mentioned conclusions can be applied to proper harvesting and management of forest ecosystems.

: The paper describes the basic potential methods and their costs of maintenance of forest lands in protective zones under high-voltage power lines (HVPL) 400 kV and 220 kV. In the present situation and with available information and data, it was possible to accomplish the average cost calculations for the whole area of the Czech Republic. The paper analyses the following mechanical and chemical methods of maintenance of forest lands: full-area scrub clearing with power saw (PS), selective individual scattered clearing of trees with PS, full-area scrub clearing by milling, full-area scrub clearing by the application of herbicides and arboricides, selective individual scrub clearing of individual trees by cutting followed by spray treatment with arboricides. The maintenance of forest lands in zones of HVPL (scrub clearing) by milling belongs to the economically most convenient mechanical methods, for example when removing 3,000 trees.ha^-1, the cost of this option is 20,000-23,000 CZK.ha^-1ha in a period of 3-year periodic frequency, while the most expensive method is selective individual scrub clearing of scattered individual plants with PS at costs of around 84,000 CZK.ha^-1.