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....
1. Defoliation by cankerworms in 1979 was significantly less in 1978 treated shelterbelts than in untreated shelterbelts. 2. Most shelterbelts treated in 1978 retained enough foliage by late June 1979 so that adjacent crops were protected from wind. 3. Aerially applied Bt at a rate of 1/2 lb./acre provided shelterbelt...
A needle miner, Coleotechnites sp., defoliated approximately 3,100 acres of ponderosa pine, Pinus ponderosa Laws. on the Flathead Indian Reservation, Montana, during 1978. Three other small areas in the Missoula Valley were infested also. Overwintering populations of larvae are low; thus, light defoliation is expected in 1979 in presently infested...
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...
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...
Preliminary analysis of data from this study in the mountains southwest of the Anaconda Copper Smelter, an industrial source of SO2 and heavy metal particulate, reflects a complex pattern of pollutant impact. The differential effect of smelter emissions on plant life in the study area is best explained by the...
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...