Mountain pine beetle populations began building in the Kootenai National Forest in 1972. Infestations now encompass an estimated 48,599 acres of lodgepole pine type and 615 acres of ponderosa pine type. Approximately 25 percent of the high-risk stands, 17 percent of the moderate-risk, and less than 1 percent of the...
Mountain pine beetle activity has increased from about 350 infested trees in 1972 to over 1,200 infested trees in 1974 on the Bitterroot National Forest. The majority of infestation occurs in second-growth, overstocked, ponderosa pine stands in the West Fork Bitterroot drainage. An increase in number of trees killed is...
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 increased to epidemic levels on the Kootenai National Forest in 1972. Nearly 397,000 trees containing almost 32 million board feet have been killed. More than 84,000 trees will probably be killed in 1978. Infestation has the potential to intensify in high hazard stands, and some increase...
Mountain pine beetle populations reached epidemic levels on approximately 4,600 acres in Glacier National Park in 1972. Infested trees increased from 4.9 in 1972 to 10.9/acre in 1975. Majority of trees killed since 1972 were 12 inches d.b.h. and larger in size. Sufficient large diameter lodgepole pine exists to maintain...
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 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...
A mountain pine beetle infestation has been active in the St. Regis area since 1964. Heaviest tree mortality occurred during the period 1969-70. The infestation has continued to decline since 1970. Over 2 million board feet of lodgepole and ponderosa pine were killed during the outbreak. Overstocking resulted in slow...