Further Observations on Douglure in a Dendroctonus pseudotsugae Management System
Oxford University Press
Douglure, a 4: 1: 1 mixture of frontal in, camphene, and alpha-pinene, respectively, was very effective in inducing mass attacks by the Douglas fir beetle, Dendroctonus pseudotsugae Hopkins, on live Douglas fir, Pseudotsllga menziesii (Mirb.) Franco. Attack densities were lower in baited mass-attacked trees than in naturally attacked trees. However, mass-attacked trees that were adjacent to a baited tree achieved attack densities comparable to naturally attacked trees.
Baiting of individual live trees was more efficient in aggregating the pest population within 1 chain of the bait trees than was a pattern of baiting trees in groups of 3. Presalvage baiting with Douglure should maximize the removal of Douglas fir beetle-infested trees.
Deadtrapping with Douglure-baited plywood panels coated with Stikem Special® docs not appear to be effective in a pest-management program, probably because of the overwhelming effectiveness of natural pheromone sources.
Pitman, G.B.; Vité, J.P. Further observations on douglure in a Dendroctonus pseudotsugae management system. Environ. Entomol. 1973. 2, 109-112