A supplemental Douglas-fir tussock moth egg mass evaluation was made within three quarter sections north of Poison, Montana, during April 1975. These areas were being considered for a pilot control project of a nucleopolyhedrosis virus spray. Results from the April evaluation showed these areas no longer qualified as sites for...
Dwarf mistletoe is known to reduce both height and diameter growth and thus reduce the yield of an infested stand. This comparison of two similar stands--one healthy and the other infested--gives an indication of the impact of this parasite. The healthy stand has produced 1.5 times the board foot volume...
Many nonmerchantable trees on the proposed control areas are moderately to heavily infested with dwarf mistletoe. Control by sanitation-thinning is desirable and is both biologically and economically sound.
Many understory trees on proposed control areas are lightly to moderately infested with dwarf mistletoe. Control by thinning/ sanitation after logging will reduce infestations to a tolerable level and significantly increase volume yields in the future. The cost-benefit ratio of control is favorable.