An infestation of a defoliating weevil, Magdalis gentilis LeConte, was
reported in July by Hank Manning, Judith Ranger District forester, Lewis
and Clark National Forest. The infestation occurs in precommercially
thinned stands of lodgepole pine, Pinus contorta var./atifblia Engelm.
in the Moose Creek drainage. Although damages caused by M. gentilis...
We conducted a combination road/plot impact survey for dwarf mistletoe in lodgepole pine on six East Side National Forests in 1978. The road survey showed infestation percentages ranging from 28.2 on the Custer to 52.4 on the Beaverhead. The plot survey showed annual cubic foot volume losses ranging from 106M...
Stepwise multiple regression techniques were used to statistically analyze the relationships between damage caused by the pine needle sheath miner Zellaria haimbachi (Busck); a needle miner, Oenerostoma etrobivorum (Zeller); sugar pine tortrix, Choriatoneura Zambertiana (Busck); and ambient and foliar concentrations of fluoride in lodgepole pine (Pinue contorta v. Zatifolia Engelm.)...
A permanent study was established in 1970 and 1971 to measure the impact, spread, and intensification of dwarf mistletoe on precommercially thinned Douglas-fir and lodgepole pine in Montana. Mean diameter growth on all plots was reduced 21 percent in Douglas-fir, but the reduction is only significant at the 0.15 level....
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...
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....