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The paper analyses the root system development in the artificially established stands of Douglas fir aged 10, 20, 30, 60 and 80 years on aerated soils (Cambisols) without skeleton. On these sites, the Douglas fir develops a uniform root system of substitute taproots and anchors, which has great predispositions to assure the good mechanical stability of trees as well as its resistance to sudden changes in upper soil horizons. Several anchors growing in positive geotropic direction shoot from the stem base, several slant anchors shooting from the side of the stem base turn into the positive geotropic direction of growth. In humus horizons, horizontal skeletal roots shoot from the stem base, which turn into lower soil horizons in an "elbow-pipe" manner and from which shoot positively geotropically growing anchors. Trees of Douglas fir develop this type of root system already at an age of twenty years.

The purpose of this study is to facilitate the detection of provenances relevant to the reforestation practice in Bulgaria. Studies were carried out in a Douglas-fir provenance trial plantation established at an altitude of 800 m a.s.l. on the northern slopes of Rila Mountain. To establish the productivity, assess the stands and rank provenances biometric procedures, methods of descriptive statistics and ANOVA were used. The diameter at breast height, average height, dominant height, total growing stock volume, assortment timber structure and survival of trees were analyzed in the stands of 55 Douglas-fir provenances. The provenances were characterized in terms of productivity of forest stands at 20 years of age and their ability to produce high quality timber was evaluated. Provenances: Newhalem No. 4 (Seed zone 402), Darrington No. 7 (Seed zone 403), Parkdale No. 19 (Seed zone 661) and Idanha No. 29 (Seed zone 452) have been recommended. Among the recommended provenances are those with growing stock volume with branches from 296 to 354 m³.ha^-1, mean annual increment from 14.8 to 17.7 m³.ha^-1 and dominant heights of up to 17.9 m.

Because the image fire smoke segmentation algorithm can not extract white, gray and black smoke at the same time, a smoke image segmentation algorithm is proposed by combining rough set and region growth method. The R component of the image is extracted in the RGB colour space, the roughness histogram is constructed according to the statistical histogram of the R component, and the appropriate valley value in the roughness histogram is selected as the segmentation threshold, the image is roughly segmented. Relative to the background image, the smoke belongs to the motion information, and the motion region is extracted by the interframe difference method to eliminate static interference. Smoke has a unique colour feature, a smoke colour model is created in the RGB colour space, the motion disturbances of similar colour are removed and the suspected smoke areas are obtained. The seed point is selected in the region, and the region is grown on the result of rough segmentation, the smoke region is extracted. The experimental results show that the algorithm can segment white, gray and black smoke at the same time, and the irregular information of smoke edges is relatively complete. Compared with the existing algorithms, the average segmentation accuracy, recall rate and F-value are increased by 19%, 21.5% and 20%, respectively.

The purpose of this work was to monitor the effects of the environmental factors include temperature, precipitation and sun radiation on some physiological aspects of Q. brantii trees in the forest stand involved with the oak charcoal disease during a growing season. We designed a systematic random sampling and all trees were examined for disease status. Our result showed that 70.96% of the trees with different intensities are affected by the charcoal disease. Accordingly, values of predawn leaf water potential (PWP), midday leaf water potential (MWP) and chlorophyll variables showed significant difference in classes of oak charcoal disease. Linear regression analysis showed that the values of PWP, MWP and chlorophyll are changing at the high temperature. Mean of canker length are 20.5 cm and 51.7 cm in class 2 and 3 respectively and there is a great relation between PWP value and canker length (r² = 0.914). Canker length also has a linear relation with MWP values (r² = 0.627). Drought stress affected the physiological functions of oak trees and considerably reduced their defense potential against pathogen agents.

Monitoring of visitor arrivals is one of the tools which help to ensure good-quality and suitable management of the respective area. This paper is aimed at the monitoring of visitor arrivals when the visitors are counted automatically using a field counting device, namely a pyroelectric sensor. In 2015, visitor arrival monitoring using a pyro sensor was conducted on the selected forest roads in the Křtiny Training Forest Enterprise of Masaryk Forest. Since this method should be employed in another project, it was necessary to find out whether the pyroelectric sensor is a reliable tool and whether it can be used for further research. The aim of this paper is to perform a regression analysis of the data collected at the selected site in order to determine whether the pyroelectric sensor provides relevant information. Two data sets acquired during the first week of the monitoring of visitor arrivals at the single site will be compared. The one set includes data obtained by automatic monitoring using the pyro sensor, the other set contains data gained by means of manual counting by students of the Faculty of Forestry and Wood Technology. Two directions of visitor flows were monitored - in and out. The data were statistically processed using the ADSTAT software. Results of the regression analysis show that the results of the visitor arrival monitoring carried out using a pyro sensor differ just slightly from those gained by manual counting.

Beech (Fagus orientalis Lipsky) is the most industrial commercial tree species among more than 80 broadleaved trees and shrubs in Hyrcanian forests. In this study some of the silvicultural properties of beech were studied under a shelterwood cutting system in a regeneration unit of 25 years old stand in Sangdeh forests of Iran. Tree height, diameter, canopy cover, variety of species, frequency at different stages of growth (seedling, sapling, thicket and pole) and tree density at juvenile phase were recorded in 431 circular 1,000 m² sample plots before and after shelterwood cutting. Results indicated that tree density in the diameter at breast height (dbh) class of < 20 cm increased during shelterwood cutting. Canopy cover of regeneration unit was 78.5% in 1957, while in 2000 and after the shelterwood cutting it reached 59%. Growing stages of regeneration were 14% sapling, 21% thicket, 24% small pole and 41% pole. The shelterwood method has not been very successful in our study area due to a number of technical and potential problems.

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.

This study was conducted to assess the effect of forest road as a corridor on local biodiversity. For this purpose, 10 segments in a 10 year-old road were selected in Neka-Zalemrood forest in Hyrcanian zone. At each of the segments, we established two 100-m transects perpendicular to the road centre line, within which we sampled three macroplots of an area 400 m². In each macroplot, nine quadrant microplots 2 × 2 m in size were set up for regenerated tree species and herbaceous plant survey. Chemical and physical parameters of soil were measured in laboratory. Results indicated that thirty-six herbaceous species and 13 regenerated tree species were recorded within the area of 100 m from the road verge. At the different distances from the road verge and both down and up-slope, the ground cover of Carex sylvatica and Rubus caesius L. as well as regeneration density of Carpinus betulus L. were higher compared to other species. Menhenick, Margalef, Shannon and Simpson indices were higher at the distance of 0-20 m than at the distances of 40-60 m and 80-100 m. Camargo and Smith-Wilson indices decreased when increasing distance to the road. These results are expected to provide critical information for decision makers and land managers for managing plant species and maintaining the integrity of biological communities.

The issue of afforestation of non-forest land (e.g. agricultural land use) is currently a significant trend in land management. Sustainable development and maintenance of its ecological stability are among the reasons. The paper compares the 30-year development of the beech stand originated from artificial regeneration on former agricultural land in the area where the Ipeľ River rises in central Slovakia. Two methods of tending were used on three long-term research plots (LTPs) established at the age of 20 years: negative crown thinning, free crown thinning and the third LTP was left to its spontaneous development. The results confirmed the positive impact of tending on the development of these stands. Compared to naturally regenerated stands under comparable site conditions, their higher quantitative production was found. Regarding the qualitative production expressed by the number of trees of selective quality, the worst results were obtained on the control plot. Based on these results, it is recommended to pay more attention to the planting stock quality used for afforestation.

The Scots pine communities are common forest types in Central Europe, however, the general model of changes resulting from cyclical management practices is still unclear. The aim of this paper is to present the changes in species diversity during the development of managed Scots pine stands and to distinguish main stages of vegetation succession. The examined stands were divided into six age classes: ≤ 10 years old, 11-20, 21-40, 41-60, 61-80, 81-120 years old. Data from our study suggest a division of the stands into three main stages of succession on oligotrophic (low nutrient) sites. The first stage is associated with the youngest stands before the canopy formation (< 10 years), the second stage with young closed-canopy stands (11-40 years) and the third stage with the maturing, pre-mature and mature stands (> 40 years). The first stage was characterised by the highest value of the Shannon index, the highest number of vascular plant species, the highest cover of lichens but the lowest cover of bryophytes. There was a group of non-forest cryptogams, exclusive for that stage. In the second stage, there was a significant decline in the Shannon index, the cover of bryophytes increased and the cover of lichens decreased. Cladonia species were characteristic of that succession stage. The third stage was characterised by the lowest species richness, moreover, the cover of bryophytes was highest and the cover of lichens was lowest. Common coniferous forest species were characteristic of the final stage before clear-cutting. Generally, after stand removal the communities indicated higher species diversity than previous forest communities. The final forest plant associations were not determined solely by late-successional species.Forest management appeared to substantially influence changes in diversity and the course of succession.

The forest road network is invariably linked to forestry and logging, as it transports logging products and products needed for forestry activities. Constructing and maintaining it in good condition are essential. In view of the economic situation in the country and the financial difficulties faced by forest holdings in the construction and maintenance of the forest road network, it is necessary to determine the optimal hauling distance and the optimal density of the primary forest road network. The analysis of the forest road network in the territory of the State Educational Experimental Forestry Enterprise "Georgi Avramov", Yundola village, showed that the density of the primary forest road network is several times higher than the national average, namely 20.31 m'.ha-1, yet it does not reach the optimal road network density calculated at the farm, of 30.9 m'.ha-1, at a hauling distance of 323.15 m.

One of the important issues both in the political discussion about climate change and in forest ecosystem research is carbon sequestration. In this paper, we estimated soil carbon sequestration (SCS) in two Persian oak forest stands of different origin (seed and coppice). Soil samples were taken at two soil depths (0-15 and 15-30 cm) and locations (under the tree crown and open area) in each oak stand. Results showed that surface layers (0-15 cm) had the highest soil carbon sequestration ranging from 41.2 t.ha-1 to 47.9 t.ha-1 for both oak forests. The total SCS was higher (between 79.5 and 89.07 t.ha-1) in open areas of the two forest stands than under the crowns of oak trees. Finally, the amount of total SCS in seed originated forest (SOF) (86.52 t.ha-1) was significantly greater (P < 0.05) than in coppice forest (CF) (77.70 t.ha-1). The results indicate that a relatively large proportion of C loss in CF is due to overgrazing, forest degradation and conversion to coppice forests in the study area.

The research was aimed to estimate above- and below-ground carbon stock in Tankawati natural hill forest of Bangladesh. A systematic sampling method was used to identify each sampling point through Global Positioning System (GPS). Loss on ignition and wet oxidation method were used to estimate biomass and soil carbon stock, respectively. Results revealed that the total carbon stock of the forest was 283.80 t.ha^-1 whereas trees produce 110.94 t.ha^-1, undergrowth (shrubs, herbs and grass) 0.50 t.ha^-1, litter fall 4.21 t.ha^-1 and soil 168.15 t.ha^-1 (up to 1m depth). The forest in the study area is a reservoir of carbon, as it has a good capacity to stock carbon from the atmosphere. To realize the forest sector potentiality inBangladesh, the carbon sequestration should be integrated with the Clean Development Mechanism (CDM) carbon trading system of the Kyoto Protocol.

A study of work accidents in forests has shown that dangerous trees play an important role in forest accidents. Despite the importance of safe working environments for forestry operations, the definition of these areas in natural forests is still unclear. Dangerous trees are considered those snagged with broken branches and a canopy or ones with dead trunks and stumps that have a hazard potential to the forest workers. This study investigates the frequency of these trees in the managed and unmanaged forests in the Caspian forests of Iran. In order to do the study, 15 circular plots with a total area of 1,000 square metres in two studied parcels were selected and the trees, according to their dangerous characteristics, were evaluated. The final results indicated that 66 and 50 trees per hectare had signs of being dangerous trees in the managed and unmanaged stand, respectively. A comparison of the average number of dangerous trees in the two studied parcels using the Mann-Whitney test indicated a significant difference so that the average number of dangerous trees in the managed parcel was more than the ummanaged parcel. Trees with broken branches had the highest frequency in the managed stand, while trees with a dead trunk or stump, a broken branch and canopy in the unmanaged forest were more than the other classes. Considering the relative frequency of the dangerous trees in the two study areas, identifying them could be one of the main attempts in logging safety. The existence of hazardous trees with different risk classes in each of the forest stands requires the development of specific safety instructions to deal with the risks of each tree.

Thaumetopoea pityocampa (Lepidoptera: Notodontidae) is one of the major forest pests and causes serious damage especially to pine trees. Mechanical and chemical methods are used in the control of this pest in Turkey's forests. In recent years, a chemical control has been the most preferred method against this pest. Due to the chemical control's harmful effects on the environment and the human health, alternative methods of control are being emphasised today. There are many studies on the use of plant oils against pests in agricultural areas. However, studies on the effect of plant oils against the pine processionary larvae are very limited. In this study, commercial oils containing 8 different essential oil types (thyme oil, peppermint oil, poppy oil, garlic oil, rosemary oil, pine oil, sage oil, lavender oil) were applied in 3 different doses (0.1%, 0.5%, 1%) and 4 repetitions against the pine processionary larvae. The experiments were conducted at 65% humidity and 25°C in laboratory conditions. The study was monitored for five days and the results were evaluated through the mortality rates. On the 5th day of the study, 1% dose of thyme oil was found to be most effective with 100% mortality followed by the poppy oil (95%), the sage oil (95%), the garlic oil (90%), the rosemary oil (70%), and the pine oil (45%). The peppermint (40%) and lavender oil used in the study were found to be ineffective. As a result of the study, it was determined that thyme oil, poppy oil, sage oil, and garlic oil were effective against the pine processionary larvae and that they had the potential to be used in the control of this pest.

The cones of the giant sequoia contain red, water-soluble crystalline substances known as cone crystals. The inhibitory effect of this extracted material on Norway spruce, Scots pine and European larch germination was newly examined. Sown seed representative samples without and with added cone crystals were compared after their incubation in the same appropriate conditions. All these cases have brought compelling evidence that cone crystals totally inhibit germination. However, the chemically inhibited seeds being rinsed afterwards germinated very well. This switch effect caused by the cone crystals of the three above-mentioned conifers proved to be a nonspecific tool. Seeds of the giant sequoia, naturally affected by the cone crystals, were sown as rinsed and non-rinsed samples. Both the samples, grown on a wet peat substrate in appropriate conditions for 16 weeks, exhibited an equal, yet very low viability of 1.3% at the same time. This low number, fixed in seeds of the tree being far from the ecological optimum, does not allow any disputation with other authors.

Currently, it is difficult to identify correct data on wood sources and their consumption in the Czech Republic. Official statistics of wood production are relatively limited to obtaining data that accurately captures the objective wood production, which would enable the observation of the direction or consumption of particular tree species or products. This uncertainty is then transferred to the wood flow for industrial and energy processing, and it is not possible to compose a detailed picture of how much wood and which sources enter into the wood processing and how large the total material flow is. The aim of this paper is to present an option for how to determine this lack of valid information that enables clear outcomes necessary for decision making by means of the recalculation of wood sources consumed in the Czech Republic, using the data of processing capacities and foreign trade. The reverse model better expressed a conversion value of roundwood into the products and allowed optimal approximation in the wood sources assessment.

The present study has been done to evaluate the impact of pure ash stand and mixed stand with beech on the herb layer biodiversity and soil properties in the forests of Noor city. There is a unique stand of ash in the forests of Noor city and at 1,900-2,100 m a.s.l., which is rarely seen like that in the northern forests of Iran. Shannon-Wiener diversity indices (H'), Simpson index of dominance (D), Margalef richness (R₁) and Pielou's evenness were used to analyse biodiversity. Sampling was also conducted to investigate physical and chemical properties of soil (bulk density, acidity, electrical conductivity, soil moisture, soil lime, nitrogen and organic carbon) in each sample plot and at two depths (10 and 20 cm). The total number of 26 soil samples (13 soil samples at either depth) in pure ash stand and 24 soil samples (12 soil samples at either depth) from this type of stand mixed with beech were taken. The results of plant species biodiversity showed that between the pure ash stand and the stand mixed with beech there is a significant difference at the 99% probability level in Shannon-Wiener diversity, Margalef richness, and Simpson dominance. There is also a significant difference at the 95% probability level between the two stands under study in Pielou's evenness index. The results of soil factors also showed that at the depth of 10-20 cm acidity factor showed a significant difference from its adjacent stand at the 99% probability level. There is also a significant difference at the 99% probability level in acidity (0-10 cm) and soil moisture at the depth of 10-20 cm between the two areas, but there is not any significant difference between the areas under study in electrical conductivity and lime factors at the two depths and also in moisture content at the depth of 0-10 cm. It should be noted that between the stand and soil nitrogen, organic carbon and bulk density parameters at both depths (0-10 and 10-20 cm) a significant difference at the 95% confidence level is shown.

The study was carried out in the experiment with 16 provenances of common ash (Fraxinus excelsior Linnaeus) and 2 provenances of narrow-leaved ash (Fraxinus angustifolia Vahl) at a series of 5 parallel trial plots established in a gradient from lowland riverine to upland ravine sites. The role of the site, ash species and the provenance of common ash proved to have significant effects on the intensity of ash dieback (ADB) associated with the infection by Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya at the age of 20 years. Narrow-leaved ash was healthier, surviving and growing better than common ash on the trials situated inside as well as beyond its natural range. The ADB intensity was lower in the medium altitude and more easterly located trial plots with a more continental climate. The provenance of forest reproductive material proved to have a significant effect on the ADB damage and survival rate as well as the growth of ash across the trial plots of the experiment.

The paper presents the results from three different experimental plots in mountain areas in Slovakia. Annual interception losses varied in mature forest stand in Poľana Mts. (850 m a.s.l.) in mixtured (spruce, fir, beech) from 10.6 to 23.5%, in spruce from 20.5 to 35.5% and in beech forest from 8.8 to 26.9%. Horizontal precipitation reduces long-term average of interception loss by 3.2% (mixtured and spruce) and 2.9% for beech forest. Decline process in supramontane spruce forest has significant influence on interception process in climax spruce stand in Červenec. Mean biweekly interception loss in the central crown zone near the stem during growing seasons was 76.9% in living and 69.2% in dead forest. In the gap canopy interception loss was observed 11.7% in living and 17.9% in dead forest, in the dripping zone under the crown periphery 11.1% in living and 25.7% in dead forest. Results from the experimental catchment Lomnistá dolina showed that forest ecosystems increase the variability of rainfall amounts infiltrated to the soil environment in mountain watersheds, interception loss varied in a wide range: from 42 up to -10% due to altitudinal influence, tree species composition, stand age, and horizontal precipitation occurence.

The black walnut (Juglans nigra L.), an introduced species into the Czech Republic, is planted for its production of valuable timber. A systematic study of the black walnut growth rate at different localities and consequently the creation of standard volume tables under Central European conditions therefore appear to be of high relevance. The aim of our study was to reveal the black walnut growth pattern in its pure stands in two riparian forests along the Morava and Svratka River (Strážnice locality and Židlochovice locality, respectively). To describe and to compare relationships among diameter at breast height (dbh), tree height and age, we used a forest management plan and measured 573 and 670 trees in pure sample stands at Strážnice and Židlochovice, respectively. We found out that the measured mean DBH and mean height were consistently higher in Strážnice, however the relationships of DBH to height, age to DBH, and age to height showed the same pattern at both localities. The mean heights of trees were 16.3, 24.1, 28.7, 31.9, and 34.5 m in 20, 40, 60, 80, and 100 year age classes and were consistently taller in comparison with other, mainly European, regions. Therefore our results suggest the high potential of black walnut in timber production in riparian forests in the Czech Republic, mainly in the South Moravian region.

In North America, Gremmeniella abietina, European race (GaEU), was reported in 1975. Our objective was to follow the spread of GaEU on red pines growing on flat land and on slope. Annual height infection varied significantly on flat land, ranging from 60 to 110 cm in 1991 to 0 to 50 cm in 1992. On the slope, pines in the bottom were killed by the disease, but survived on the top. Favorable conditions follow a horizontal line about 10 m over the lower elevation and are probably related to fog or mist. The horizontal disease spread over a 3-year period was only 20 m and this is mainly explained by the absence of ascospores in North America.

We investigated the growth parameters of 20-year-old plantations of Pinus nigra J.F. Arnold and Picea abies (Linnaeus) H. Karsten and their impact on understory woody plants and we compared them with a natural stand in above-timberline mountain areas. 30 sample plots (each of 400 m2 in area) were systematically established on each site. Tree height, DBH, collar diameter, crown diameter and crown length of all trees were measured in each sample plot. The results of the diameter growth analysis of both species covered by this study showed higher numerical values in P. nigra than in P. abies. On the contrary, what was observed for data concerning height growth, showed higher numerical values in P. abies than in P. nigra. These conclusions showed that P. nigra has a lower slenderness ratio than the other species and is therefore more resistant to the adverse weather. Considering the effects on biodiversity, the planting of P. nigra showed a significant increase in density and species richness of woody plants while it decreased the diversity and evenness compared to the natural stands and plantations of P. abies.

The paper analyses stand structure and production on two experimental forest stand series of mature pure and mixed Scots pine stands, growing on natural Scots pine sites in the Czech Republic. Sessile oak was the main admixed species. In mixed stands, Scots pine constituted the dominant level of the stand, admixed species grew mostly as subdominants. Admixture increased stand densities and aboveground biomass production compared to pure stands. Sessile oak with the 20-30% number share within the Scots pine stand led to an increase of the Scots pine tree dimensions and mean stem merchantable wood (DBH ≥ 7 cm) volume compared to the pure Scots pine stand of similar density. The Scots pine and sessile oak slenderness ratios increased in mixed stands compared to monocultures, however, the stand mechanical stability was not threatened.

The paper provides the results of a detailed analysis of timber volume and the most important crown variables of black locust (Robinia pseudoacacia Linnaeus) based on an experimental plot in southern Hungary. At the age of 20 years the crop trees belonged to different height classes. If the volume of the mean tree from height class I is considered as 100%, the volume of the mean tree of class II is 44.0%, and the mean tree of class III is only 30.3%. In case of timber volume per 1 m² crown surface, the values are 72.9 and 61.7%. The DBH of trees showed a positive linear correlation with crown diameter (r = 0.942). Additionally, there were also positive linear relationships between crown diameter and volume (r = 0.901), between crown length and volume (r = 0.721) as well as tree height and crown length (r = 0.661). The variation of crown indices is height even within the same stand and indicates the importance of following a selective thinning operation method.

Recently the use of fungal entomopathogens against bark beetles has gained increasing attention throughout the world and researchers continue to seek highly pathogenic fungal isolates for controlling beetle pests. In the present study, the efficacy of three entomopathogenic fungi, namely Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae sensu lato (Metchnikoff) Sorokin and Lecanicillium lecanii (Zimmerman) Zare & Gams, was tested against Polygraphus major Stebbing, 1903 under laboratory conditions. Each fungal suspension contained 1.0 × 10⁹ spores of fungi in 1 ml. An insecticide - Cyclone was also used as positive control in the experiment. The mortality caused by these fungi was recorded in treated branches and petri plate assay. In treated branches, B. bassiana and M. anisopliae s. l. caused higher mortality, i.e. 57.77 and 46%, respectively, after 10 days of treatment and 98 and 92.77%, respectively, after 20 days of treatment. The results of the petri plate assay revealed that P. major adults were highly susceptible to both applied fungal species and insecticide. However, B. bassiana and M. anisopliae s. l. caused higher percentage mortalities after six days of treatment, i.e. 100 and 91.66%, respectively. The percentage mortality caused by application of the insecticide was 69%. L. lecanii was observed to be significantly less virulent (mortality 46.66%) in all fugal treatments. After observing the promising nature of the three entomopathogenic fungi by testing them, we arrive at the conclusion that the tested fungi have a potential for the control of P. major, and further field experiments are warranted to investigate their efficacy under more practical conditions.

Individual companies need to know their financial condition. They have a wide range of methods and procedures to create a system of the financial and economic analysis of a company. The analysis is focused on the evaluation of a specific group of methods for predicting the financial health of a business entity. Evaluations of the financial situation of a company are divided into point methods, mathematical and statistical methods and neural networks. The individual methods differ from each other in difficulty, in the extent of the analyzed areas and possibilities of application. The aim of this work is to assess the possibilities of using selected methods of comprehensive evaluation of companies as a tool for an analysis of the position of each company in the branch. The suitability and feasibility of each method are tested on a selected group of companies. Quick Test, Tamari Model, Beaver Model are included in this work. Based on the results, improvements and recommendations for the practical use were suggested. The results showed that the best predictive methods are Quick Test and Tamari Model, because they are quick and unequivocal when assessing the analyzed companies. An inappropriate prediction method is the Beaver model, which uses only two financial indicators to evaluate companies.

Calculation of Skid Trail Spacing (STS) is an important option to minimize the total costs of skidding. Construction of many skid trails increases the construction cost, it also results in more degradation on different levels in forests. On the other hand, by constructing less skid trails, winching cost will increase, and in many cases, the skidders will exit from skid trails. This research was carried out in four districts under management of Mazandaran Wood and Paper Industry Company with the aim of determination of Optimum Skid Trail Spacing (OSTS) for an HSM skidder. In this study, a continuous time study method to the nearest second with stop watch was used. The results indicated that the time modelling of winching was mainly affected by load volume and winching distance. By using the time modelling of winching, the winching cost is estimated and then by combining that with the skid trail cost graph, the OSTS graph is calculated. Finally, 95 meters is calculated as optimum skid trail density in this study.

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.

The strong market competition forces forest owners to find innovative approaches to forest management, and business models are becoming integral parts of successful innovations and business strategies. This paper deals with the applicability of a business model (as an innovation tool) for small forest owners. The main objectives were to design a business model applicable in the forestry sector and to find the innovative business alternatives for the small-scale forest owner reflecting the local situation (in a case study in the Czech Republic). The extended business model CANVAS was used. The embedded data was evaluated on the software developed at the Savonia University in Finland where business opportunity and competitive advantage were the main evaluation criteria. As a result, a proposed strategy was advised to be followed. The biggest added value of the extended CANVAS model is giving an objective and unbiased evaluation of the situation of small forest owners. The business model design proved a usable and applicable tool to be used in forest management, for the research has shown that the quantitative data should be complemented by qualitative research in order to get the complex view.