EFFECTS OF SEMIOCHEMICAL BAITING ON THE ATTRACTIVENESS OF FELLED AND UNFELLED LETHAL TRAP TREES FOR SPRUCE BEETLE, DENDROCTONUS RUFIPENNIS (KIRBY) (COLEOPTERA: SCOLYTIDAE), MANAGEMENT IN AREAS OF HIGH AND LOW BEETLE POPULATIONS

Abstract

AbstractA two by two factorial experiment in a randomized complete block design tested single and combined effects of tree felling and semiochemical baiting on the attractiveness of spruce (Picea spp.) trees treated with monosodium methanearsenate (MSMA) to Dendroctonus rufipennis (Kirby) in British Columbia and Alaska. In British Columbia, tree felling and semiochemical baiting had significant effects on attack density, but in Alaska only tree felling had a significant effect. Semiochemical baiting had a significant effect on within-tree attack distribution in British Columbia but cot in Alaska, regardless of the felling treatment. The felled treatment captured more beetles than the not-felled treatment regardless of the baiting treatment in British Columbia, but only in the absence of a semiochemical bait in Alaska. The differences between the two locations may have been caused by lower temperatures and beetle population density in Alaska. Effective spruce beetle management with MSMA-treated trees requires tree felling, and beetle capture can be improved with the use of a semiochemical bait.