Damage to Douglas-fir cones by Choristoneura occidentalis
Journal of Economic Entomology
Oxford University Press
The budworm Choristoneura occidentalis Freeman was found to be a serious pest to Douglas-fir cones in Montana and Yellowstone National Park, Wyoming. A total of 41,250 cones was examined or placed in rearing containers during the summers of 1967 and 1968. Of the cones collected in 1967, 36% were infested with budworm larvae. One budworm often feeds on more than one cone during its development. Most of the seed in budworm-infested cones is destroyed.
Dewey, J.E., 1970. Damage to Douglas-fir cones by Choristoneura occidentalis. J. Econ. Entomol. 63, 1804-1806