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...
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....
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...
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,...
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...