الوصف:
Epidemic populations of the western spruce budworm persist in the
Northern Region. Aerial surveys made in August 1976 showed a decline
in the acreage of aerially visible defoliation. In northern
Idaho, the defoliated area dropped from 831,487 acres in 1975 to
655,711 acres in 1976, down 21 percent. Surveys in Montana found a
net decrease in defoliation of 11 percent, down from 2,797,986 in
1975 to 2,496,274 in 1976.
Egg mass surveys made in September and October 1976 indicate that
defoliation will be light on the Clearwater and Nezperce National
Forests and moderate on the Idaho Panhandle National Forests, Idaho,
in 1977. Defoliation in Montana during 1977 is expected to be light
on the Flathead, moderate on the Kootenai, and heavy on the Beaverhead,
Bitterroot, Deerlodge, Gallatin, Helena, Lewis and Clark, and
Lolo National Forests and the Flathead Indian Reservation.