Dwarf mistletoes reduce tree height and diameter, and thereby cause a reduction in volume production. We estimate that volume reduction in Montana is about 33.2 MM cubic feet per year. Mistletoe effects are problems in some areas because of the demands we have placed on the Forests for goods and...
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...
Mortality from various causes was recorded in a Douglas-fir tussock moth, Orgyia pseudotsugata McD., outbreak southeast of Coeur d'Alene, Idaho, in 1974. Observations began June 27 when about 50 percent of the larvae were second instars and continued until pupation. Within a 35-day period, there was a 93 percent average...
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...
This publication discusses the environmental requirements of needle diseases, their potential impact on tree vigor, when disease levels signal a problem, and what you can do to minimize damage.
This study was conducted to investigate why root disease centers east of the
Cascade crest tend to be larger in diameter and more abundant than their counterparts to
the west, within subalpine forest stands of central Oregon. The trend in a 290 km² study
area appeared opposite of what was...
Insect damage was extensive to Douglas-fir, ponderosa pine, western white pine, and western larch cones at most seed production areas surveyed in 1979. From 70 to 100 percent of the cones from several collecting periods were injured. Moderate damage (40-70 percent of cones injured) occurred to Douglas-fir, ponderosa pine, western...
Potential problem pests found were Armillaria root disease, pocket gopher, western pine shoot borer, and white pine blister rust. Early detection of problem pests allows management actions to be taken if needed to prevent serious impacts. Unit managers should check the areas periodically and call on pest management specialists to...