The aim of the study was to verify whether oil extracts prepared from plants of 22 selected species contained substances reducing feeding of Hylobius abietis beetles in shoots of Pinus sylvestris. Experiments were conduced under laboratory conditions. A statistically significant reduction was shown for the size of damage on pine twigs treated with oil extracts of Lycopersicon esculentum leaves. In contrast, extracts of Papaver rhoeas and Junlans regia leaves increased feeding of large pine weevil beetles.

Investigations were conducted in central western Poland, in Scots pine stands aged 25-36 years. The population size of Hylobius abietis larvae was determined on stumps left after felled pine trees in eight stands. It was found that on stumps located in strip roads the number of weevil larvae was significantly higher than on stumps found outside those roads.

Two methods to determine the population size of foliophagous insects wintering in forest litter were compared in 52 Pinus sylvestris stands. It was found that the method consisting in the measurement of the number of insects in the stand in 10 small plots was not markedly better than the method consisting in the measurement of the population size under the crown of one tree.

In the course of forest management works in the Karkonosze National Park a total of 630 circular sample plots arranged in a 200 × 300 m graticule were established using the mathematical statistical method. Litter samples were collected from the centres of these plots in the autumn of 2002 and 2003 in order to determine the species composition of groups of rove beetles (Staphylinidae) and to prepare their zoocenological characteristics. A total of 136 beetles, belonging to 32 taxa, were found in samples. Identified groups were analysed using zoocenological indexes for montane and subalpine forests. It was found that the dominant species were Othius subuliformis Steph., Geostiba circellaris (Grav.), and Amischa analis (Grav.). In the groups of the montane forest 15 taxa were distinguished with a distinct domination of Othius subuliformis and Geostiba circellaris. Staphylinidae groups of the subalpine forest consist of 26 taxa and indicate a domination structure characteristic for undisturbed ecological systems with high frequencies of Othius subuliformis, Amischa analis and Geostiba circellaris.

In the course of forest management works in the Karkonosze National Park a total of 630 circular sample plots arranged in a 200 × 300 m graticule were established using the mathematical statistical method. Litter samples were collected from the centres of these plots in the spring and early summer of 2004 in order to determine the species composition of groups of rove beetles (Staphylinidae) and to conduct their zoocenological characteristics. A total of 83 beetles, belonging to 22 taxa, were found in samples. Identified groups were analysed using zoocenological indexes for subalpine and montane forests. It was found that the dominant species were Geostiba circellaris (Grav.), Atheta tibialis (Heer) and Amischa analis (Grav.), as well as Othius subuliformis Steph. In the groups of the montane forest eight taxa were distinguished with a distinct domination of Geostiba circellaris. Spring Staphylinidae groups of the subalpine forest consist of 21 taxa and indicate a domination structure characteristic for undisturbed ecological systems with high frequencies of Atheta tibialis and Amischa analis.

Flammulina velutipes isolate ability of growth, wood colonization and wood decomposition was studied in vitro. The experiments were done at three temperatures 4°C, 15°C and 22°C. The investigated isolate started to grow in one day after incubation at 15°C and 22°C. Flammulina velutipes mycelium colonized and decomposed wood the most intensively at 22°C. Oak wood was both the least intensively colonized and least effectively decomposed in comparison to beech and birch wood irrespective of temperature and incubation time (three and six months).

The presented paper discusses the results of investigations on the biomass of a stand which developed on the fresh mixed coniferous forest site. The precise knowledge of data concerning the weight of individual tree elements can provide information allowing researchers to carry out other experiments associated with, for example, the determination of the biomass as the raw material base, the assessment of nutrients withdrawn from the forest with the harvested raw material as well as other types of information. The performed investigations revealed that, in the case of the examined site, the total over ground weight of pine trees amounted to 264 500 kg/ha of which the greatest proportion fell on the bole timber (approximately 212 t/ha), whereas the smallest share – on thicker branches (of the diameter over 4 cm). The performed moisture content experiments allowed the authors to determine the dry weight of individual parts of trees. The percentage proportion of individual parts was similar to the weight structure of the fresh parts. The highest difference was determined in the case of bark – its dry weight was by 2 percent higher in comparison with the fresh weight.

The study was an attempt to assess the accuracy of “Volume increment tables for pine” by Albert Dudek in pine stands aged 35, 50 and 88 years, from the Forestry Experimental Station Murowana Goślina. In the 35-year old stand the smallest secondary percentage error in the determination of current volume increment of the stand for a 5- -year growth period was obtained using variant IV of the tables (–2.69%) and in case of a 10-year period for variant I (1.62%). In the 50-year old stand for the shorter growth period it was variant II (–2.21%), while for the longer period it was variant V (–7.94%). In the oldest stand it was table variant III (12.60%) and IV (–6.77%), respectively. Using variants II, IV and V of the tables in the analysed stands current volume increment was determined in diameter subclasses. Irrespective of the applied table variant (in individual diameter subclasses), both positive and negative errors, and the biggest errors (absolute values) were found for trees from the lowest and higher diameter subclasses. In most cases the accuracy of the determination of current volume increment in the analysed stands using tables was consistent with the accuracy expected by their author. Variant V of the tables makes it possible to most accurately estimate volume increment of the stand, irrespective of its age and the length of the growth period.

The comparative evaluation of the roe deer (Capreolus capreolus L.) males being existent in four diverse regions of the Cracow surrounding (Fig. 1) in respect to physiographic and climatic forms have been established. The body weight, measurements and weight of the skull and measurements as well as form of the antlers were assumed to be the estimation criteria of individual quality of the roe deer males. The lowest individual quality had been affirmed to roe deer that being existent in Jurrasic Scienic Parks and the highest to males from Miechów Upland and Proszowice Plateau. It has been proved that skull dimension of roe deer from the Cracow surrounding had not concessed to the best Polish roe deer populations.

The mycelium isolate of Daedalea quercina (L.): Fr. was examined in vitro according to its ability to wood decay of 25 tree species both European, introduced and exotic, not existing in our geographical latitude. The range of trophic preferences of this fungus was defined and the speed of wood decay of individual tree species was investigated.