The mountain pine beetle reached epidemic levels in second-growth 80-yearold ponderosa pine stands on the Ninemile Ranger District in 1969. The
outbreak increased through 1971 and spread over 30,000 acres. Heavy
infestation occurred on about 2,600 acres within this area. A two-stage
survey was used during 1972 and 1973 to...
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...
The mountain pine beetle, Dendroetonus ponderosae Hopk., has been at epidemic levels in second-growth ponderosa pine stands in the Ninemile area of the Lolo National Forest and surrounding private lands since 1969. An impact survey, using two levels of photography and a small ground sample, was conducted to estimate a...
Mountain pine beetle infestations have increased in second-growth ponderosa pine stands in the Garnet Mountains since 1971. The extremely dry 1973 season resulted in an increase of Ips engraver beetle activity that was responsible for over half of the tree mortality in 1973. Commercial thinning is recommended to alleviate the...
This report includes information obtained in both 1983 and 1984. Beginning in 1983, only four of the original six permanent plot locations in the State would be revisited. The two in the southwestern part of the State--Centennial Valley and Madison River--were not visited because of reduced beetle populations and 111.1...
For the fourth year since their establishment, the six permanent plot locations in Montana were revisited following beetle flight in 1982.Beetle populations remained low in five of the six areas. Only in the Murr Creek plots did newly attacked trees represent an epidemic beetle population. In the Centennial Valley location,...
The series of mountain pine beetle infestations existing on the Plains/Thompson Falls Ranger District, Lob National Forest, since 1971 continued into 1988. While some infestations are waning, others are increasing. The potential for beetle-caused mortality exists in threatened, but as yet uninfested stands. Management alternatives are discussed.
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 reached epidemic levels in second-growth ponderosa pine stands on Bureau of Indian Affairs and private lands on the Crow Indian Reservation. Approximately 9,106 trees containing 420,266 merchantable board feet were killed from 1971 to 1973. This is about 24 percent of the merchantable ponderosa pine in stands...
Mountain pine beetle reached epidemic levels in the Lazier-Meadow Creek drainages on mixed ownership in 1972. A total of 118,486 trees with an estimated volume of 5,666,124 board feet was killed from 1972 through 1974. Presence of overstocked, mature, nearly pure lodgepole stands, coupled with favorable weather conditions, are believed...
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 reached epidemic levels in 1972 in the Stoney Creek drainage, Ninemile District, Lolo National Forest, Montana. A total of 8,082 trees with an estimated volume loss of 34,356 board feet has occurred from 1972 to 1974. Buildup ratio was 1:1.2 from 1972 to 1973, and 1:1.8...
The mountain pine beetle has impacted over 5 million hectares of pine forests in the Rocky Mountains region in the United States. Although some beetle-killed stands are available for salvage harvesting, there are many uncertainties in harvesting beetle-killed stands including safety, costs, recoverable products and their values. These uncertainties impose...
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,...
The mountain pine beetle infestation existing on the Crow Indian Reservation (IR) since the early 1970's, and later developing principally in the western portion of the Northern Cheyenne IR, continued into 1984. Survey results indicate the infestation is still building on both Reservations. To help develop beetle management strategies appropriate...
Six Montana areas in which permanent mountain pine beetle trend plots were established in 1979 were revisited in 1980. Results of the visit show infestation intensity decreased significantly in Centennial Valley, decreased slightly in the Madison River plot area, and increased almost threefold in the Murr Creek area. Beetle populations...
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...
This report documents the establishment of a study to determine the effect of thinning on incidence of mountain pine beetle, Dendroctonus ponderosae Hopk., infestation in second-growth ponderosa pine stands in western Montana.
Although insufficient time has passed for a similar study in Oregon to yield a solid base for a...
Mountain pine beetle populations increased in 1979 in the Thompson River drainage to levels predicted following the 1978 attack period. New attacks in 1979 averaged 27 per acre. Current estimates indicate another 25 percent of the remaining lodgepole pine could be killed in 1980.
Thirty permanent mountain pine beetle population trend plots were established in each of six areas in the state in 1979. Infestation levels ranged from 0 to 47.8 new attacks per acre. The potential for increased mortality is considered high for all areas. Each area will be evaluated for 5 years...
The mountain pine beetle infestation in Corral, Little Corral, and Cache Creeks on the Crow Indian Reservation, Montana has been increasing for the past several years. Trees killed per acre averaged 38.8 in 1979. Our predictions for the future trend of the infestation, plus management alternatives to lessen its severity,...
This report contains an overview of the present mountain pine beetle infestation in lodgepole pine stands on Federal, State, and private lands on the Plains Ranger District. Particular emphasis is placed on the potential for beetle mortality in the Thompson River drainage where recent ground surveys show more than 21...
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...
This report contains a brief history of selected mountain pine beetle infestations and the potential for infestations in high hazard stands on the Tally Lake Ranger District. Management alternatives to lessen the severity, or reduce the possibility, of infestations are discussed.
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...
Mountain pine beetle populations developed to epidemic level in lodgepole pine stands in 1973. Approximately 426,355 trees were killed on 3,433 hectares in 1976. Infestations are expected to intensify in areas of current infestation and develop in uninfested stands. It is predicted that 1,722,288 trees will be killed in 1977....
Mountain pine beetle developed to epidemic levels in lodgepole pine stands in the Thompson River drainage in 1971. Approximately 506,616 trees are infested on 4,444 hectares. Based on buildup ratios, infestations are expected to intensify; develop in uninfected stands; and kill about 1,763,024 trees in 1977. Salvage logging of infested...
The mountain pine beetle infestation on Bureau of Land Management lands in Centennial Valley has increased from about 500 acres in 1977 to more than 7,000 in 1979. Average number of trees per acre killed has more than quadrupled, increasing from 9.8 in 1977 to 47.8 in 1979. Predictions for...
Mountain pine beetle infestation was detected in stands on the east side of Glacier National Park and the adjacent Blackfeet Indian Reservation in 1979. Infestation in the Park now encompasses an estimated 215,882 acres. About 200 acres are infested on the reservation. In areas sampled, number of trees killed per...
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, Dendroctonus ponderosas Hopk., reached near epidemic levels in lodgepole pine stands in the Sulphur Creek-Black Butte area. Lodgepole pine are probably more susceptible due to the overstocked conditions of stands, and high incidence of girdling of the base of trees by porcupines. The infestation in this area...
A mountain pine beetle outbreak developed on the north face of Shook Mountain in 1972. Beetle populations increased, and have continued at an epidemic level since 1973. Surveys show 404,798 ponderosa pine containing 12,173,940 bd. ft. volume of merchantable timber; and 20,875 lodgepole pine containing 730,625 bd. ft. volume of...
A pilot survey was conducted to evaluate the effectiveness of using multistage sampling techniques to measure annual and cumulative mortality on a State-wide basis with acceptable statistical reliability, timeliness, and cost. Within the State of Montana, aerial surveys showed about 986,000 acres of lodgepole pine infested with mountain pine beetle....
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...
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...