Alternative methods for controlling Douglas-fir beetles, Dendroctonus pseudotsugae Hopkins (Coleoptera: Scolytidae), were examined in terms of the number of beetles removed from a population and in terms of beetle flight activity near treated sites. Methods that were tested included pheromone-baited Lindgren funnel traps, standing, continuously pheromone-baited trees, standing, temporarily pheromone-baited trees with bait removed after beetles began invading the tree, and single felled trees. Funnel traps captured more than twice the number of beetles over the flight season than a baited or felled trees. The tree methods did not differ from each other in the number of beetles captured. Trees in all three methods became saturated within the first 20–30 d of flight. Baited traps continued to catch beetles during the whole test period. Beetle flight remained active around continuously baited trees even after beetle attacks ceased. Beetle flight around temporarily baited trees ceased after the trees became saturated. Density of beetles per tree did not differ between different sized decks of felled trees. Large decks (with 9 to 12 trees) absorbed three times the beetles than small decks (with 3 to 4 trees), and nine times as many as did single felled trees. Spillover to neighboring trees from baited trees or traps is minimized when baits are removed after initial attacks. A tree deck of three or four felled trees of DBH ≈40 cm is equivalent to one trap in terms of the number of beetles removed. Trees in a deck become saturated within the same time span as trees in the other methods. Single felled trees or decks produce no spillover into the neighboring stand.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.