Densities of Hibernating Ips typographus in the Forest Litter Around Attacked and Killed Spruce Trees, with Records of Spring Emergence and Flight Patterns

1993

12 S.

18 Lit. Ang.

Bandaufführung

37975

Large numbers of adult Ips typographus, emerged from brood trees in the autumn, were found hibernating in the forest litter. Therefore, in control operations during epidemic conditions, there is a positive control effect of removing infested trees before the new beetle generations leave them for hibernation in the ground. - The beetle density in the litter around attacked and killed spruce trees decreased rapidly with increasing distance from the tree. The sequence of emergence from the ground coincided well with flight trap catches. Results also showed that among beetles establishing a second brood, newly emerged adults were were establishing their first brood.