In Snežnik-Javorniki fir-beech forests (Omphalodo-Fagetum) research was made about fir bark beetles (Pityokteines curvidens, Pityokteines spinidens, Cryphalus piceae). It lasted from 5. 4. 2015 to 10. 12. 2015 in two altitudinal belts (under 800 and above 800 m a.s.l.). Twenty, during windfall fallen fir trees (Abies alba Mill.) were marked and measured. Every 14 days we counted bark beetle entry holes on the tree. We collected 20x20cm bark samples on three trees per researched altitudinal belt (later 7 samples), for determination of species in the laboratory. The first swarming of P. spinidens on the lower altitude occured in the beginning of May and the second one in the second half of August. First swarming on the higher altitude occured at the end of May and the second one in the beginning of August. Of the bark beetles researched, the P. spinidens presence was the highest, it was bigger on the lower altitudes. Compared recorded bark beetle entry holes (from 0,00 to 0,14 entry holes per running decimeter) with determination data (more than 1 entry hole per dm2 ) from Regulations on the Protection of Forests for European spruce bark beetle outbursts, suggested no outburst occured. The factors in the researched area, that influenced the vitality of European silver fir: glaze ice, windbreak (stress), altitude with temperature, occurrence of fir bark beetles, Armillaria spp., larvae of both buprestidae and cerambycidae.
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