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...
Investigations were conducted to understand the epidemiology of Fusarium on containerized Douglas-fir seedlings. Types and importance of Fusarium inoculum sources, relationships between seedling infection and symptom production, amounts and types of diseases that occurred throughout typical growth cycles, and the importance of secondary pathogen spread were investigated. Levels of Fusarium...
For the fourth year since their establishment, the six permanent plot locations in Montana were revisited following beetle flight in 1982.Beetle populations remained low in five of the six areas. Only in the Murr Creek plots did newly attacked trees represent an epidemic beetle population. In the Centennial Valley location,...
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...