Leś. Pr. Bad., 2008, 1: 15-19.

Kora zamarłych świerków jako miejsce zimowania owadzich drapieżników
związanych z kambio- i ksylofagami
Bark of dead infested spruce trees as an overwintering site of insect predators associated
with bark and wood boring beetles

Jacek Hilszczański
Instytut Badawczy Leśnictwa, Zakład Ochrony Lasu, Sękocin Stary, ul. Braci Leśnej nr 3,
05-090 Raszyn, fax: 022 7200397, e-mail: hilszczj@ibles.waw.pl

Abstract. Insect predators are important enemies of beetles regarded as pest, especially during period of low densities of host population. Overwintering predatory insects (Coleoptera, Raphidioptera) were collected in fotoeclector traps from the bark that was taken of in winter under snow level from the base of standing spruce trees killed by Ips typographus (L.) and Tetropium fuscum (F.). Insect predators were present in bark of all trees. On trees killed by I. typographus predators were more abundant than on trees with T. fuscum. Diversity and assemblage of species was similar although the lack of Raphidia sp. on trees with I. typographus and domination of Crypturgus sp. and Corticeus sp. on those trees was observed. Removing of trees killed by bark and wood boring beetles and debarking of stumps during autumn and winter could have negative effect on insect predators overwintering in bark under snow level. Those measures have no distinct effect on suppression of pest when their population is not abundant.

Key words: Ips typographus, Tetropium fuscum, natural enemies, insect predators, Coleoptera, Raphidia sp., overwintering, Picea abies.