Mortality from various causes was recorded in a Douglas-fir tussock moth, Orgyia pseudotsugata McD., outbreak southeast of Coeur d'Alene, Idaho, in 1974. Observations began June 27 when about 50 percent of the larvae were second instars and continued until pupation. Within a 35-day period, there was a 93 percent average...
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...
In conjunction with a proposed suppression project against the Douglas-fir tussock moth in northern Idaho, more than 1,000 larvae were collected from sample plots throughout the 32,000-acre treatment area. We had hoped to determine naturally occurring mortality factors which may have contributed to lower than anticipated population levels. Reared on...
The objective of this report is to describe the current increase in Douglas-fir tussock moth (Orgyia pseudotsugata McDunnough) activity in northern Idaho and Montana. The report also relates current conditions to historical and future trends and larger scale increasing tussock moth activity in surrounding western states.