Search
You searched for:
Start Over
Forestry
Remove constraint Forestry
Author
United States. Forest Service. Northern Region. State & Private Forestry
Remove constraint Author: United States. Forest Service. Northern Region. State & Private Forestry
Subject
Western spruce budworm -- Montana
Remove constraint Subject: Western spruce budworm -- Montana
Material Types
Article
Remove constraint Material Types: Article
1 - 8 of 8
Search Results
-
3. [Article] Potential for defoliation by western spruce budworm in Douglas-fir stands in eastern Montana, 1975
Aerially visible defoliation by the western spruce budworm, Choristoneura occidentalis Freeman, increased from 149,250 acres in 1973 to 649,319 acres in 1974 on five eastern Montana National Forests. An ...Citation -
4. [Article] A three year evaluation of Douglas-fir cone and seed insects in Montana and Yellowstone National Park
A 3-year evaluation of Douglas-fir cones in Montana and Yellowstone National Park, Wyoming, showed the western spruce budworm, Choristoneura occidentalis Freeman, and midges were the most common and injurious ...Citation -
5. [Article] Potential for defoliation by western spruce budworm in northern Idaho and Montana, 1977
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, ...Citation -
6. [Article] Western spruce budworm egg masses for predicting defoliation potential in the northern region : progress report
An attempt was made to predict western spruce budworm defoliation using egg counts from plots in the Douglas-fir type east of the Continental Divide in Montana, the Douglas-fir type west of the Continental ...Citation -
7. [Article] Potential for defoliation by western spruce budworm in Douglas-fir stands in Montana, 1976
Aerial surveys of six Montana National Forests in 1975 found a 22.1% increase in the area of visible defoliation caused by the western spruce budworm. It is estimated that 2,278,804 acres of Douglas-fir ...Citation -
8. [Article] Western spruce budworm defoliation trend relative to weather in the Northern Region, 1969-1979
Western spruce budworm defoliated area in the Northern Region has differed significantly across three discrete geographic zones during the past decade. Aerially visible defoliation in northern Idaho increased ...Citation