An advancing process of ageing of stands in Poland and Europe allows for predicting and increasing in the supply of large-dimension timber. The research compares selected qualitative characteristics of the timber of trees with large breast-height diameters (equal to or larger than 40 cm) with those of thinner trees on the example of Norway spruce from the region of the Beskidy Mts. A group of thicker spruce trees was characterized by a higher overall share of trees with wood defects, including visible knots and symptoms of overgrown knots as well as a smaller share of trees with injuries, rot and curvatures in comparison with the thinner ones. The absolute size of rot on the cross-section of the stem was larger in thicker trees. They were also characterized by a smaller average width of annual rings. The groups compared did not differ significantly as to the height of location of defects situated as first from the stem base.

The article shows the effectiveness of the process of grinding arbomass remaining on logging area. In the research undertaken Meri Crusher MJ 2.3 DT was subjected to scrutiny; the crusher was aggregated with a 1.4 Crystal tractor. In order to establish the actual effectiveness of grinding, the results were measured before and after the utilization of chip residue. The analysis showed that a decrease in dimension of chip residue was greater in its length than in its diameter. The achieved effect of grinding the arbomass appeared to be satisfying in terms of possibilities of a mechanical surface preparation before its regeneration.

The performed investigations concerned the effect of the application of different methods of management of cutting residues and ways of soil preparation on height changes of a five-year old pine cultivation. Both methods of residue management and ways of soil preparation exert a significant influence on the height of cultivation. Out of the applied five methods of management of clear-cutting residues, the following two turned out most favourable: a) the method which involved chopping of the residues and mixing them with the surface soil layer and b) leaving intact felling residues on the soil surface. On the other hand, the best way of soil preparation was ploughing furrows by a double-furrow plough with a simultaneous softening of the furrows with a subsoiler.

The survivability of a 5-year old Scots pine cultivation is strongly influenced by the ways of soil preparation and methods of management of the post clear-cut residues. The highest Scots pine survivability was determined on the cultivation established on surfaces on which post clear-cut residues were left, irrespective of the way these residues were treated. A significantly worse survivability was found on surfaces on which branches with needles were either burnt or removed altogether. On the other hand, the best method of soil preparation from the point of view of pine tree survivability was ploughing ridges using a rotary tiller. Ploughing furrows using LPz-75 and U-162 ploughs was found to reduce significantly the survivability of pine trees.

The aim of the present study was to characterize red deer stags harvested in the hunting grounds of the Tuchola Forests, based on carcass weight and antler weight and type. It was found that the average weight of carcass and antlers of stags harvested over the study period was 95.78 kg and 2.05 kg respectively. Eight-point stags and spickers were encountered most frequently (33.28% and 21.43% respectively). The average carcass weight of stags representing particular age groups was as follows: group I – 89.65 kg, group II – 120.29 kg, group III – 136.62 kg. Antler weight in the above age groups reached 1.66 kg, 3.55 kg and 5.90 kg respectively.

In years 2002-2004 eight pairs of experimental surfaces, one from the 3rd and one from the 4th age class, were established in pure pine stands in the Lubin Forest District. In each of these sample plots crown defoliation, the condition of the assimilation apparatus, height increment and shoot vitality of 25 trees of the main stand were assessed. Differences between mean defoliations were compared using for this purpose the standard error of the difference of two means (for P = 0.95). The performed analysis was carried out for each of the experimental surfaces and for the given entire age class during three experimental periods (i.e. years 2002-2003, 2003-2004 and 2002-2004) as well as for pairs of surfaces and age classes in the consecutive three years of observations (2002, 2003 and 2004).

The article shows relationships occurring between the age of a tree, a social class of tree position in the stand, and the volume and share of juvenile, maturing and mature wood. The object of the study were Norway spruce stands representing age classes II (from 21 to 40 years old), III (41-60 years old) and IV (61-80 years old), grown in mountain forest sites. The zones of juvenile, maturing and mature wood were determined on the basis of the proportion of late wood to early wood share in annual growth ring. Wood made inside leafy branches and within the influence of assimilation apparatus shows different structure and quality if compared with wood made of long way from the assimilation apparatus. That is why we mark juvenile and mature wood. In general juvenile wood is inseparably connection with a strong influence of assimilation apparatus, i.e. with branches of the tree. Juvenile wood is found in every tree and from the point of view of its practical application it is a disadvantageous element, limiting the possible utilization of the wood material.

Analyses of chemical composition of beech (Fagus sylvatica L.) and oak (Quercus robur L.) wood from healthy and damaged trees have been conducted. Infrared spectra of lignin isolated from the investigated wood have been recorded and analysed. Tree health was determined on the basis of ramification structure of the upper part of the crown according to the Roloff [1989] classification. Beech wood obtained from trees of the ages 80-145 years came from Pomerania and the Carpathians. Oak wood from trees of 84-147 years old came from the Podlasie and Wielkopolska region. The tested wood was cut from the butt-end parts of logs. The chemical composition of the wood, both beech and oak, obtained from trees differing in health levels was very similar. No influence of geographical provenance of beech and oak wood on its chemical composition was observed. The analysis of infrared spectra of lignin samples from oak wood relative to tree health and geographical provenance did not show significant differences. On the other hand, in the case of beech wood, some differentiation in IR spectra of lignin relative to tree health was observed.

Trees infected by Heterobasidion root rot are more exposed to the results of strong winds. In January 2007, a strong wind which passed among others over the Experimental Forest District Zielonka caused significant losses in the stands. The objective of this work was to verify whether the roots of the wind-fallen trees were settled by Heterobasidion annosum. The presence of root rot was found in 83% of roots, and the presence of the pathogen was identified in 53% of the studied trees.