Trapping western pine beetles with baited toxic trees

Abstract

Baited toxic trap trees—trunks of living trees sprayed with an insecticide and then baited with an attractive substance—were tested in California to kill western pine beetles attacking ponderosa pine. The attractant was the triplet pheromone mixture of brevicomin, frontalin, and myrcene. Insecticides were lindane, Sevin, permethrin, and deltamethrin. All insecticides were effective at certain concentrations in killing beetles at the baited tree. Adjacent nonbaited trees were often attacked, but such trees were effectively protected with both preattack and postattack sprays. Numbers of beetles killed at active baited toxic trap trees for a full season varied widely between localities, years, and treatments, ranging from about 100 to over 550 per square foot (0.093 m²) of bark surface. Sex ratio of killed beetles was about 1:1, and no unusual effects of treatments on predators and other insects were noted. There was some indication that trapping may have reduced subsequent beetle activity in the area. Comparative studies with mountain and Jeffrey pine beetle suggest that the insecticides are probably effective against them but that the currently recommended attractants are not.

Citation

Smith, Richard H. 1985. Trapping western pine beetles with baited toxic trees. Res. Note PSW-RN-382. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 9 p.