Mountain pine beetle infestations have continued at epidemic level in
lodgepole pine stands since 1969 in the West Gallatin River drainage.
This infestation has increased at about a 1.9:1 buildup ratio annually.
Since the outbreak began in 1969, surveys indicate that approximately 22,354 merchantable size trees have been killed with...
Emerged beetles were first collected July 17 and peak emergence occurred between August 10 and 26, 1975. Density of attacks averaged four per 0.5 ft. 2 (0.05 m2). Parent to brood ratio was 1:4.6. Thirteen associate insects, representing six families of Coleoptera and one of Diptera, were recovered. Associates included...
Mountain pine beetle has occurred at epidemic level in lodgepole pine stands in the west Gallatin River drainage since 1969. Infestation now encompasses about 5,500 acres. Since 1969, approximately 463,212 trees, with an estimated volume of 20,529,244 board feet have been killed. Approximately 69 percent of the stands on the...
Mountain pine beetle populations developed to epidemic level in 1970 on the Hebgen Lake Ranger District. Infested acreage increased from 78,000 in 1977 to 79,061 in 1978. More than 4 million trees (238 MMBF) were killed in 1978. Cold temperatures during December 1978 may cause a significant decline in the...
Mountain pine beetle populations developed to epidemic level on the Bozeman-Gallatin Ranger District in 1969. Approximately 146,000 acres are currently infested. Since 1969, over 350 MMBF have been killed. It is predicted that over 4 million trees could be killed in 1978. Infestation is predicted to intensify in high-hazard stands....
Mountain pine beetle populations reached epidemic level on the Hebgen Lake Ranger District in 1970. Infested area increased from 6,680 acres in 1970 to 78,000 acres in 1977. Buildup ratio of trees killed in 1976 to trees killed in 1977 is 1:8. Approximately 1,700,000 trees, containing 175 MMBF of merchantable...
Mountain pine beetle developed to epidemic level in lodgepole pine stands in 1969 on the Gallatin District and in 1970 on the Hebgen Lake District. Epidemic infestation occurs on 53,437 hectares. Infestations will intensify in most areas currently infested and develop in uninfested stands, and in excess of 2 million...
A multistage sampling survey to measure annual and cumulative mortality of lodgepole
pine by mountain pine beetle was conducted
on the Beaverhead and Gallatin National
Forests, 1978-79. The survey area, 270,000
acres, was stratified into three intensity classes
from aerial sketchmapping. This was followed
by large scale (1:6,000) aerial photography,...
