The use of Ripley’s K(t) function for analysis of spatial structure of tree stands has recently become easier due to the growing availability of advanced software. Unfortunately not every data set is suitable for analysis with classical estimator of K(t) function. Large directional differences in density of trees in analysed region cause that estimators suggest aggregated distribution of tress even if it is not true. This paper presents the review of proposals to solve this problem based on dividing of the analysed region into homogeneous sub-regions. Analyses carried out on separate sub-regions can furnish viable information about spatial structure of tree stand. Besides, examples of such analyses made with commonly available non commercial software are presented.

The paper presents the results of the isolation and identification of fungi from Quercus robur L. acorns infested by acorn major pests: Curculio glandium Marsh. and Kenneliola spp., and larvae of these insects. Acorns were collected in 2003, in three locations in Poland from the forest floor and from the nets suspended above the forest floor. The most frequently fungi isolated from acorns colonized by C. glandium was Alternaria alternata (Fr.) Keissl., and colonized by Kenneliola spp. were yeasts and A. alternata. Acorns collected from the nets were more often infected by A. alternata, Lecythophora sp., Pezicula cinnamomea (DC.) Sacc., Aspergillus and Cladosporium species, while acorns from the forest floor were often colonized by Ciboria batschiana (Zopf) N.F. Buchw. and species from Penicillium and Fusarium genera. The most frequently isolated fungi from C. glandium larvae were: Fusarium sporotrichioides Sherb., F. stilboides Wollenw., Penicillium spp. and Pestalotia clavispora Atk. and from Kenneliola spp. larvae were: A. alternata, F. sporotrichioides, Penicillium spp. and P. clavispora.

The study is an attempt to determine share of sapwood and heartwood in stems of European larch trees from II and III class of age, grown in conditions of fresh coniferous mixed forest site (BMśw), fresh forest mixed site (LMśw), fresh forest site (Lśw). The highest hare of heartwood was observed in stems of European larch in conditions of fresh forest site Lśw, and the smallest in conditions of fresh coniferous mixed forest site (BMśw). Differences were also observed within the investigated classes of age, and higher share of heartwood observed in III class of age. The smallest share of heartwood characterized codominant trees and the highest dominant trees (from main tree stand in Kraft classification).

The paper presents the productive potential of the State Forests woodland over the years 1991-2005. Changes that occurred in that period were also analysed and explained. The research showed a distinct increase in forest productivity as measured by stand volume, its net increment, and its average increment. There was a favourable change in the species and age structure of timber. Wood harvesting was also on the rise. This upward tendency was possible due to an increase in timber resources in the recent years and to a forest policy seeking to prevent any decrease in the timber quality of the standing crop.

The crushing of the logging residues was carried out on a forest area, on a mixed fresh coniferous site (BMśw). The weight of the logging residues which were left behind on the clear cut area, after taking away the round wood assortments was 47 t. The object of the analysis was a Meri Crusher MJS-2.0 DT crushing machine powered by a Valtra T-190 tractor. The crusher was 2000 mm wide and the power of the tractor was 190 HP. During the analysis the quantity of the biomass to be milled and the productivity of the milling operation itself were determined. Based on given technical parameters of the crusher (the rpm of the PTO, number of cutters, diameter of the drum and the driving speed of the tractor), the rpm of the working drum, the linear velocity of the cutters, the power and torque of the working drum and the productivity of milling were determined. Based on the analysis of working movements of the machine, the total force on all the cutters as well as the average force per one cutter were calculated. It was found that the average force on one cutter was 770 N.

The investigations were carried out in selected Scots pine (Pinus sylvestris L.) stands in Gidle, Koszęcin, and Złoty Potok forest districts (Regional Directorate of State Forests in Katowice). The majority (89.2%) of analyzed 212 Scots pine tree-tops and branches, left in the forest after cuttings, were infested by cambio- and xylophagous insects (Curculionidae – 19 species, Cerambycidae – 4 species). The mean number of brood galleries in a single piece of the examined material was 64. The following insect species were characterized by the highest values of dominance, frequency, and dominance structure: Pityogenes bidentatus, Pogonocherus fasciculatus, Pissodes piniphilus, Pityogenes quadridens, Pityophthorus pityographus, and Magdalis frontalis. Three different insect communities and 63 associations of a definite dominance structure were distinguished. Also preferences of the most abundant species in respect of diameter and bark thickness of 0.5-meter-long sections of tree-tops and branches were determined. The majority of insect species infested top and branch segments 2.6-4.5 cm in diameter with the bark 2 mm thick. Treatments aiming at reduction of reproduction of secondary insect pests on Scots pine cut off tree-tops and branches are proposed.

From among 392 Picea abies trees growing at the height of 700-800 m above the sea level in the Beskid Sądecki mountain range of the Carpathians (49^o35’ N, 19^o31’ E, southern Poland), infested by cambio- and xylophagous insects, 110 (28.1%) were also attacked by Ips amitinus (Eichh.). This bark beetle infested most willingly the weakened standing trees of age classes III-V (i.e. 41-100 years old) as well as trees recently overthrown, broken, and felled. It was most abundant in the middle part of the stem where the bark was 2-3 mm thick, infesting 38.4% of its length on the average. On a single tree I. amitinus always occurred in associations of cambio- and xylophagous insects composed of 2-12 species. There was only one generation of I. amitinus in the year, composed of the main brood and the sister brood. Its life-cycle is presented against a background of phenology of forest plants. There were three larval instars. Dimensions of all developmental stages and individual components of brood galleries are also given. I. amitinus plays an important role in killing weakened P. abies trees. The trap trees commonly used against Ips typographus turned out to be very effective also in the control of I. amitinus.

“Uroczysko Wielkie Łunawy” belongs to objects which can be distinguished for their considerable floristic values. Varied and slightly deformed flora of this small object comprises 192 species of vascular plants derived from 60 families, including 41 taxons of arborescent plants. Sites of 13 species under legal protection were identified. Valuable fragments of oak-hornbeam and riparian forest communities as well as stands close to natural ones were also found. It seems that, bearing in mind the relatively rare and well-preserved communities of the oak-hornbeam and riparian forests occurring in this region, the entire “Uroczysko Wielkie Łunawy” should be protected.

Tests showed that PF resin modification with diol esters makes it possible – when maintaining identical pressing parameters – to manufacture particleboards with improved mechanical properties and enhanced water resistance in comparison to the control board resinated with pure PF resin. The application of diol esters as modifiers of phenolic resin makes it also possible to produce – at reduced temperature or shortened pressing time – particleboards with good mechanical properties and high water resistance. However, no significant differences were observed in board properties depending on the type of diol forming the ester.