The Application of Behaviour-modifying Chemicals to Contain Infestations of the Mountain Pine Beetle, Dendroctonus ponderosae

Abstract

Five replicates of paired forest blocks containing lodgepole pine, Pinus contorts var. latifolia Engelm., infested by the mountain pine beetle, Dendroctonus ponderosae Hopkins, were chosen in the spring of 1982 in various interior British Columbia locations. Within the experimental block of each pair, one lodgepole pine every 50 m (4 trees/ha) was baited with the attractive semiochemicals myrcene, trans-verbenol and exo-brevicomin. The baiting program caused the attack in 1982 to be concentrated in and around the baited trees, whereas it was more dispersed in the control blocks. The overall ratio of 1982: 1981 attacked trees was 2.5 in the baited blocks and 1.8 in the controls, suggesting that dispersal of beetles out of the baited blocks was inhibited. Baiting of trees with semiochemicals is recommended to contain infestations within prescribed boundaries when sanitation-salvage logging cannot be completed prior to mid-summer flight of emergent brood beetles.