A synthetic pheromone of the western pine shoot borer, Eucosma sonomana Kearfott, has been used
successfully as a 'mating disrupter in northern Idaho and western Montana since 1984. Infestation
levels in treated ponderosa pine plantations declined from an average of 28 percent infested in 1983
to 5.5 percent by 1986....
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...
Mountain pine beetle reached epidemic levels in second-growth ponderosa pine stands on Bureau of Indian Affairs and private lands on the Crow Indian Reservation. Approximately 9,106 trees containing 420,266 merchantable board feet were killed from 1971 to 1973. This is about 24 percent of the merchantable ponderosa pine in stands...
Shade tree insect and disease activity within the city limits of Bozeman, Montana, were evaluated. Other than a few minor insects, the park, cemetery, and street trees are in remarkably good condition. Both the Park Department and private homeowners appreciate the value of trees in the urban environment. Recommendations on...
In 1973, two centers of defoliation by Douglas-fir tussock moth totaling 350 acres were detected near Missoula, Montana. Egg mass surveys showed two sections south of Frenchtown and one section northwest of Lolo 41, contain sufficient egg mass population to cause heavy defoliation in 1974.
A western false hemlock looper, Neptyia freeman Munroe, outbreak was detected in the late summer of 1973 at the north end of Flathead Lake. Defoliation, from barely detectable to heavy (most foliage removed from upper half of trees), occurred on Douglas-fir over about 3,000 acres
located between Somers and Kalispell,...