The mountain pine beetle, Dendroctonus ponderosae Hopk., infestation in Yellowstone National Park advanced north and eastward in 1974. New infestation centers were located along the east shore of Yellowstone Lake and south of the Promontory to the Park's southern boundary. Ground surveys indicated an average of 2.9 infested trees per...
The mountain pine beetle infestation has been epidemic in lodgepole pine in Yellowstone National Park since 1966. Infestation boundaries have advanced steadily northward and eastward. The infestation now encompasses nearly one-half of the total Park area. Surveys indicate a decline in tree mortality the last 2 years. In 1970, an...
Mountain pine beetle populations developed to epidemic level in Glacier National Park in 1972. Buildup ratio of old to newly attacked trees was 1:1.8 from 1976 to 1977. More than 12 million trees are infested on 142,871 acres. Buildup ratio is expected to exceed 1:3 from 1977 to 1978. Management...
Mountain pine beetle infestations in second-growth ponderosa pine developed in 1973 in the Little Rocky Mountains. In 1976, increasing numbers of attacked trees were observed. Current infestation intensity averages 7.1 trees per acre. Losses are expected to continue as long as stands remain overstocked and stagnated. Reduction of basal area...
Mountain pine beetle infestations in second-growth ponderosa pine have been chronic in the Little Belt and Big Snowy Mountains since 1947. In 1976, increasing numbers of attacked trees were observed. Current infestation intensity averages 82 trees per hectare. Losses are expected to continue as long as stands remain stagnates. Commercial...
Mountain pine beetle populations began increasing in Glacier National Park in 1970. Numbers of infested trees increased steadily from an average of 12 to 115 per hectare from 1972 to 1976. Total hectares of infestation have increased from 445 in 1972 to 40,419 ha in 1976. Predictive equations estimate a...
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...
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....
Windthrow occurred during late April on the Glacier View, Hungry Horse, Spotted Bear, and Swan Lake Ranger Districts, Flathead National Forest. An evaluation to determine potential for development of spruce beetle and Douglas-fir beetle outbreaks was made during late June and early July. All areas examined were classed as having...
Ground surveys on the Hungry Horse District indicate a potential for mountain pine beetle infestation in lodgepole pine. Based on elevation-latitude, mean d.b.h. and phloem thickness, and age, stands were given a susceptibility classification of high risk. An infestation in Glacier National Park may provide the beetle source. Management alternatives...