The influence of the number of sample plots on quantity of an average error of a stand volume, number of trees and increment in uneven-aged stands is presented in the study. The research was carried out in 43 stands in which 739 control sample plots were established. It was stated that at least 8 sample plots should be established for the accuracy of stand inventory at the level of 20%.

The present analysis concerns the subject of surface runoff from slanting forest roads. In the Beskid Śląski area (Silesian Beskidy Mountains), where a drainage basin was completely afforested, sections of roads were selected to measure the water running off. In each section an open top culvert was installed. The analysis contains the already mentioned measurement methodology, characteristic features of both the drainage basin and the selected road sections, results the surface runoff measurement carried out on the selected road sections and finally the results of a simulated calculation of voluminal quotient of two values: surface runoff from the drainage area roads and precipitation over the drainage basin area (q_{dr P}) and a quotient of surface runoff from the roads in the drainage area and the runoff from the drainage basin (q_{dr Q}). The following values were estimated for the 2.1 mm rainfall rate: q_{dr P} = 0.42%, q_{dr Q} = 8.92%, whereas for the 9.8 mm rainfall the values were as follows: q_{dr P} = 0.93% and q_{dr Q} = 100.13%.

In order to evaluate the fatigue of forest workers, the authors used a Japanese questionnaire. The investigations included workers employed on 30 workstations in silviculture, forest protection and forest utilization. Workers filled the questionnaire three times during the workday. The frequency of the symptoms of tiredness from the group concerning reduced activity reported by workers before the beginning of work was small and increased in the course of work reaching the highest values after finishing work. Symptoms of reduced motivations were reported by workers sporadically, with the exception of operators of harvester and forwarder where they dominated. The frequency of the occurrence of fatigue symptoms (ABC) before work amounted, on average, to 1.9%, during the break – to 8.5%, whereas after the termination of work – to 13.1%. The group of symptoms of physical fatigue was characterised by the highest frequency and scale of intensity. The most frequently reported symptoms included: thirst, back pain and stiff neck and shoulders. For the distinct majority of the examined operations, a C > A > B type of fatigue characteristic for physical jobs was observed and the only exception was the job of operators of harvester and forwarder which was characterised by the B > C > A pattern of fatigue.

The aim of this study was to determine the effects of medium composition and the amount of plant growth regulators essential for shoot initiation in the mature seeds culture of Pinus sylvestris L. For seed germination the following media were used: White’s medium, Murashige and Skoog’s medium [MS], a half of MS nutrients, B5 [according to Gamborg et al. 1968], Tisserat’s medium [cited in Bhojwani and Razdan 1990] and DCR [Gupta i Durzan 1985] marked by the symbols A-N. The above mentioned media combinations differed in the amount of cytokinin BAP (0.25-4.0 mg·dm^-3) and tidiazuron – TDZ (0.05-1.0 mg·dm^-3) and auxin IBA (0.5 mg·dm^-3). Pine shoots on DCR medium without growth regulators were the control sample. It was found that for Pine sylvestris, the Tisserat^’s medium [cited in Bhojwani and Razdan 1990] without growth regulators is the most useful medium for shoots initiation during a germination test.

The aim of the study was a preliminary functionality assessment of soil quality index (ITGL) [Brożek 2001], ground water level and vascular plant ecological indicator presented as a site grid [Różański 1996] for site quality diagnosis in reclaimed areas and in areas left for succession in the Szczakowa sand mine excavation. A comparison of results of site quality assessment on the basis of soil quality and vascular plant ecological indicator shows the greatest compatibility of site quality diagnoses in non-reclaimed areas with succession communities. It confirms the current use of methods in this category based on vascular plant ecological indicator, co called phyto-sociological methods. The paper shows the need for further studies on the possibilities of using these methods for specific post-mining areas.

The study was carried out at the turn of 2003 and 2004 in the Gaj Mały village (Wielkopolska region, Poland). The influence of Prunus domestica on the specimens of Carpinus betulus, growing as a hedge was noticed, revealing as a significant decrease in stem thickness of the other species. Hornbeam trees have the minimal value of this parameter within the zone of crown views of plum-trees and at the same time in the zone of interaction of root system of this species. The thinnest hornbeam trees cast their leaves first.

The authors attempt to find functional relations between changing parameters of technical condition of the petrol chain saw engine and the magnitude of vibrations measured on the body and the handles. The presented investigations can contribute to learning the factors intensifying vibrations and will facilitate the development of the method for making a diagnosis on the chain saw technical condition with the use of vibroacoustic signals. In addition, the authors also try to show the influence of wood cutting, apart from the engine, on the magnitude of vibrations measured on the chain saw handles.

Timber harvesting in Poland is performed with the use of manual and machine techniques with a large dynamic load. The aim of the present research was to analyse the level of energy expenditure in operators who harvest timber in a mountain spruce stand in the forest district of Nowy Targ. The technique under analysis included the performance of logging as part of late thinning with the use of a cable winch propelled by a chain saw engine. The research showed that, in the thinning technique under analysis, the elimination of manual unblocking of trees suspended during their felling increased work safety. The results also show a significant reduction of a chain saw operator’s energy expenditure from 24 kJ·min^-1 to about 17.6 kJ·min^-1. The energy expenditure reduction, which occurred in the thinning of coniferous species by means of a portable cable winch propelled by a chain saw engine, indicates a possibility to increase the humanization of the operators' work on the level of manual and mechanical techniques.

The inventory carried out on the area of the Goraj Forest Range allowed to catalogue 531 valuable specimens of arborescent plants from 48 taxons and 20 families, including 33 native taxons and 15 taxons of foreign origin. Fagus sylvatica, Carpinus betulus and Quercus robur were found to have the greatest share. The circumference of the majority of the measured plants ranged from 201 to 340 cm, although specimens measuring from 121 to 180 cm were also quite common. The health condition of almost 87% of the examined plants was assessed as very good and good. The Goraj Forest Range is a very valuable area from the point of view of dendrology. Thirty-four plant specimens growing in this forest range are covered by monumental protection, 158 specimens are characterised by monumental circumferences and 296 specimens have circumferences close to monumental. That is why 100 trees and bushes found here were recommended to be placed under protection in the form of nature monuments.

This paper reports a country wide study on the health condition and its short term dynamics in the most threatened middle-aged-to-old-growth oak stands. The field measurements and observations were carried out in the period 2001-2004, covering 52 stands in 18 forest districts. Except of the complete survey of each stand, a total of 1560 permanently marked trees were subject to detailed measurements and assessment, both conducted during the growing season and at the leafless stage, in order to comprehensively describe the variety of tree vitality aspects. It is concluded that the health status of the majority of stands covered by the present study are threatened, both in terms of their development and stability.

The total of 155 taxa of vascular plants derived from 51 families, including 32 woody plants, were inventoried in the area of the settlement. The modern flora of the explored settlement does not show traces of the human activity which had taken place here centuries ago. Native species clearly predominate over foreign ones and nearly 70% constitute meso- and oligohemerobic species indicating a low level of human pressure to the environment. The most common plants found here are those associated with thermophilic oak forests and mesophilic broad-leaved forests, nitrophilic thickets and meadow vegetation. Sites of 7 species under legal protection were identified. Stands are dominated by young trees but more than 100-year-old specimens can also be found. The authors believe that the examined area should be allowed to follow natural succession processes and long-term, periodical floristic and phytosociological investigations should be undertaken to monitor changes in its flora. The “Poganka” is a regional tourist attraction and should be made available to visitors by marking out special tourist paths close to the old site.

The aim of the paper is to present the ontogenetic quality of the roe deer and an assessment of breeding and hunting procedures for its population in forest divisions of the Olsztyn District of the Polish Hunting Association. The collected data came from annual hunting plans for the season 2002/2003 and from the records of culled males of deer in the hunting season 2001/2002. The statistical data concerned 203 hunting grounds. The gathered statistical material was used for calculating breeding indicators and ontogenic quality parameters of the roe deer in particular forest divisions, including the form of antlers, mean carcass weight and gross weight of antlers.

The aim of the study was to determine the actual influence of predators on the populations of small game animals in the hunting areas of the Warmia and Mazury region. The experiment was carried out in the area of the Game Breeding Centre in Załuski, belonging to the District Board of the Polish Hunting Association in Olsztyn, situated in the Warmia and Mazury Province in the Forest Division of Nidzica. It consists of two field hunting grounds covering a total area of 9,638 ha. Artificial nests were established in 11 diverse study sites located in the areas representative of the hunting grounds. Three trials were performed. While checking the nests placed in experiment I (after day 21), all nests (143) were found destroyed. In experiment III, during the check after seven days from the date the eggs were placed in the nests, all nests were found completely destroyed. The results of the study indicated a strong potential predatory pressure on the populations of small game animals.

Filtering dust separation proceeds in various conditions. It is necessary to determine the work factors of dust filter for each case of this method of air cleaning – first of all to select a suitable fibrous material on which the separation process of solid particles from air stream occurs. Increased relative humidity of air conveying the dust particles is always a significant difficulty for the separation process in wood dust separators. Application of unwoven fabrics with special finished active surface – hydrophobically appreted – significantly rises air cleaning of wood dust in these cases. At standard unwoven fabrics – with homogenous structure – appears an opposite interaction. The separation efficiency decreases with growth of relative humidity of the air stream.

The study investigated the effect of the modification of phenolic resin with organic acid esters, such as ethyl, butyl and pentyl acetates, on the possibility to lower pressing temperature of particleboards manufactured using ester-modified PF resin. Conducted tests showed that the applied modification of phenolic resin makes it possible, within the adopted range of pressing temperatures, to produce particleboards with considerably better mechanical properties. It also needs to be stressed that at lower pressing temperatures the effect of the applied modification is so intense that boards pressed at 160°C obtain strength values comparable or even higher than those of the control board pressed at 180°C.

One-layer particle boards with addition of particles of waste paper were manufactured. Two sorts of waste paper (mixed waste paper and waste paper bags) and two glues (urea-formaldehyde resin – UF and melamine-urea-formaldehyde one – MUF) were applied in the process. Properties of the boards (bending strength, modulus of elasticity, perpendicular tensile strength and thickness swelling after 24 h soaking in water) were examined. As a result it was found that waste paper can be a supplementary addition in the production of particleboards. Boards had sufficient properties if maximum content of waste paper should not exceed 50% (with the MUF resin) and 30% (with the UF resin).

The fitting of the tenon joint plays an important role in its functioning. Experiments were carried out in industrial conditions with the aim to investigate the execution accuracy of the tenon joint tolerated in two directions. On the basis of measurements and calculations of a series of tenon joints manufactured from two kinds of timber, namely alder and pine, the authors determined types and classes of fits of seat lengths with tenon widths and – for the same elements – of seat widths with tenon thicknesses.