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The aim of the study was to determine the effect of temperature and humidity on colonization of cambio− −xylophagous insects on Norway spruce branches in relation to the place and method of slash utilization. Analyzed branches were infested by eight species of cambiophagous and two species of cambioxylophagous, whereas the material utilization method does not substantially influence the entomofauna species composition. The most numerous were: Pityogenes chalcographus, Ips amitinus, Dryocoetes autographus and Pityophthorus pityographus. The branches treatment was a factor contributing significantly to the infestation intensity by P. chalcographus and I. amitinus, reaching a higher density of galleries on the branches spreading disorderly on the forest floor than collected in the piles. Moreover, it was found that the location of branches inside the pile determines their attractiveness to hygrophilous species with a minor economic importance. Significant differences in temperature and relative humidity inside the piles and the surrounding branches scattered disorderly on the surface during the growing season indicate that this may be an important factor influencing logging residues left in the forest infestation intensity by bark beetles.
According to the research carried out in 1998-2000 it was found that small particles of the shoots left in the orchard after pruning are the place of the numerous fungi development. It was observed that the greatest number of species appeared 12 months after winter pruning. The species colonising fragments of bark and wood included typical patogenic species, pathogens of weakness, and saprotrophs. Some of isolated species may in favourable conditions become the cause of bark and wood diseases as well as apple rot.
Field studies were carried out on 12 sample plots established in selected pure European fir stands, or stands with predominance of this tree species, in Lesko Forest District (Krosno Forest Region) and Krynica Experimental Forests. In total 200 fir tree-tops (100 in Lesko and 100 in Krynica) were analyzed. All tree-tops were infested by cambio- and xylophagous insects (Cerambycidae - 4 species, Curculionidae - 4, Melandryidae - 1, Siricidae - 1). The mean number of brood galleries per single tree-top was 76 (minimum 5, maximum 245). Cryphalus piceae and Pityphthorus pityographus were characterized by the highest mean indexes of dominance, frequency, and dominance structure. In Lesko Forest District 15 different insect associations (composed of 2-4 species) were found on tree-tops analyzed during this study. The association composed of Cryphalus piceae and Pityophthorus pityographus occurred most frequently (61.5%). It was found that the occurrence of brood galleries of some species depended on the diameter of a tree-top 0.5 m section, and the bark thickness.
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