ETHANOL INDUCES ATTACK ON TREES BY SPRUCE BEETLES, DENDROCTONUS RUFIPENNIS (COLEOPTERA: SCOLYTIDAE)

Publisher Website
Google Scholar
Abstract
When 95% ethanol was sprayed at the rate of approximately 46 ml/m2 of bark surface on the lower 1 or 2 m of standing living spruce trees, Picea engelmannii Parry – P. glauca (Moench) Voss hybrid population, 23 of 47 and 18 of 19 treated trees in two areas received one to many spruce beetle, Dendroctonus rufipennis (Kirby), attacks, whereas only 2 of 63 and 2 of 64 untreated trees, respectively, were attacked. Some of the treated trees were killed by mass attacks of the beetles, but most trees pitched out the attacks. Thus beetle attacks on essentially resistant trees were induced by the ethanol treatment. However, spruce beetles were not attracted by the ethanol treatment.