The unusually large amount of ice, snow,
and wind-damaged trees that occurred
during the winter of 1996-97 provided prime
habitat for populations of the Douglas-fir
beetle (DFB) (Dendroctonus pseudotsugae)
to build to epidemic numbers. Beetles
emerged during the spring and summer of
1998, attacking hundreds of thousands of
standing Douglas-fir...
Whitebark pine is an important reforestation species in the northern Rocky Mountains for enhancement of wildlife habitat. Production of container-grown whitebark pine seedlings at the USDA Forest Service Nursery in Coeur d'Alene, Idaho has been increasing the past several years. Diseases continue to be an important limiting factor in seedling...
Three stands along Benton Creek within the Priest River Experimental Forest, Idaho, were surveyed for diseases using previously established timber inventory plots and sample trees. These surveys provided information to aid in formation of silvicultural prescriptions by CEFES (Continuing Education in Forest Ecology and Silviculture) students. Diseases were quantified at...
Methods used to establish permanent plots in precommercially thinned and unthinned stands to monitor root disease development are described. Plots were established in 22 Armillaria-infested stands in northern Idaho and western Montana. The proportion of trees dead and infected was significantly higher for planted than for natural regeneration at the...
A synthetic pheromone of the western pine shoot borer, Eucosma sonomana Kearfott, has been used
successfully as a 'mating disrupter in northern Idaho and western Montana since 1984. Infestation
levels in treated ponderosa pine plantations declined from an average of 28 percent infested in 1983
to 5.5 percent by 1986....
Investigations of containerized western white pine, western larch, and Douglas-fir seedlings at the Western Forest Systems Nursery in Lewiston, Idaho, revealed that many seedlings were colonized with Fusarium oxysporum although they lacked severe disease symptoms. White pine seedlings were also infected with Pythium spp., probably as a result of sowing...
Armyworms are the larvae (caterpillars) of the moth Pseudaletia unipuncta Haworth. This insect is a serious pest of turf, forage, and seed grasses; small grains; and corn throughout North America. Armyworms can cause sudden, extensive damage to these grasses and grasslike plants. Note that the armyworm does not feed on...
Investigations were conducted from 1998-
2000 at the Potlatch Corporation's
Cherrylane Seed Orchard near Lewiston,
Idaho to evaluate presence and extent of
potentially pathogenic fungi on roots of
diseased stock and within the soil in current
and proposed plantation sites. The most
common group of pathogens encountered
was Fusarium spp.;...