Pine tussock moth
British Columbia, Yukon, Northwest Territories
Damage, symptoms and biologyThe pine tussock moth is normally a relatively uncommon solitary defoliator. This species however occasionally goes into outbreak on individual open grown trees in urban settings in British Columbia. One outbreak covering 26,000 ha of young ponderosa pine was recorded in Montana in 1965.
Mature larva up to 35 mm long. Head, unmarked black. Body covered with white or yellowish hairs radiating out from black tubercles; four middorsal tufts of dirty white hairs on abdominal segments 1-4. Two long black pencil tufts project forward from the first thoracic segment and three more back from the rear of the body. Bright red eversible glands on the dorsum of abdominal segments 6-7.
This species overwinters as early instar larvae under bark scales. Larval feeding resumes in spring and continues until July. Pupation occurs in July and adults emerge from late July to August, mate, and females lay eggs in small clusters on foliage. Larvae emerge soon after, feed briefly and then hibernate.
Canadian Forest Service Publications
Diet and feeding behaviour
: Feeds on the leaves of plants.
- Free-living defoliator: Feeds on and moves about freely on foliage.
Information on host(s)
The principal hosts of the pine tussock moth are Douglas-fir, western hemlock, Engelmann spruce, white spruce and ponderosa pine; other hosts include subalpine fir, grand fir, western larch, western white pine and lodgepole pine.