Dwarf Mistletoe Pruning May Induce Douglas-Fir Beetle Attacks

Abstract

Abstract Fresh attacks of Douglas-firs (Pseudotsuga menziesii) by Douglas-fir beetles (Dendroctonus pseudotsugae) were found in a campground that had trees pruned to remove Douglas-fir dwarf mistletoe (Arceuthobium douglasii) infections. All Douglas-firs with a diameter at breast height (dbh) of at least 12.7 cm were examined. Beetle attacks were found on 41% of the pruned trees and 5% of the unpruned trees. Among pruned trees, both the average number of branches pruned and the average dbh were greater in trees attacked by Douglas-fir beetles than in unattacked trees. West. J. Appl. For. 15(1):34-36.