The current western spruce budworm, Choristoneura occidentalis Freeman, outbreak on the Clearwater National Forest was first detected in 1966. Since then, the infestation has increased to epidemic proportions with over 500,000 acres of State, Federal, and private forest land visibly defoliated. In addition, incipient budworm populations are present throughout much...
An evaluation was made in 21 seed production areas and 1 seed orchard in Region 1 to identify the primary insect pests and to assess amount of injury caused. Cones from Douglas-fir, grand fir, western larch, lodgepole pine, ponderosa pine, and western white pine were collected periodically and examined. The...
The mountain pine beetle infestation in Corral, Little Corral, and Cache Creeks on the Crow Indian Reservation, Montana has been increasing for the past several years. Trees killed per acre averaged 38.8 in 1979. Our predictions for the future trend of the infestation, plus management alternatives to lessen its severity,...
Insect damage was extensive to Douglas-fir, ponderosa pine, western white pine, and western larch cones at most seed production areas surveyed in 1979. From 70 to 100 percent of the cones from several collecting periods were injured. Moderate damage (40-70 percent of cones injured) occurred to Douglas-fir, ponderosa pine, western...
Two blends (Natural and Phillips) of the western pine shoot borer pheromone, formulated as Hercon Luretape, were applied to six ponderosa pine plantations in northern Idaho and western Montana in 1984. The treatment was approximately 21.6 grams of pheromone per hectare. Significant reductions in damage have occurred in all treated...
Douglas-fir tussock moth populations are monitored annually in northern Idaho and western Montana to insure early detection of changes from endemic to outbreak population levels. Adult moth trapping in 1982 was intensified and expanded into additional areas from 1981 because of concern that with each passing year the probability of...
Trees in a Douglas-fir stand infested with western spruce budworm were treated with a systemic insecticide to protect cone and seed production at three locations in Montana during 1983. Treatments applied were (1) acephate as an Acecap implant, (2) acephate as an Inject-A-Cide injection, and (3) control. Potential cone-bearing trees...