White and grand fir are both valuable components of the mixed-conifer stand structure managed for late-successional reserves in central Oregon. However, they are often short-lived species because of high susceptibility to root diseases, defoliating insects, bark beetles, and wildfire. This study focuses on the effects of root diseases caused by...
This study examined debris flows occurring in a 125 km² study area in the Blue River watershed in the western Cascade Mountains of Oregon over a 50-year period. Debris flow occurrence was found to be concentrated in a distinct zone of high activity occupying approximately half of the study area,...
During 1997–1998, we investigated the influence of both the relative abundance of truffles, preferred food
items, and microhabitat structure on the occurrence of northern flying squirrels (Glaucomys sabrinus Shaw) in oldgrowth
forest habitat of the Sierra Nevada Range, U.S.A. Following live-trapping sessions, we searched the forest floor
for truffle diggings...
During 1997–1998, we investigated the influence of both the relative abundance of truffles, preferred food
items, and microhabitat structure on the occurrence of northern flying squirrels (Glaucomys sabrinus Shaw) in old-growth
forest habitat of the Sierra Nevada Range, U.S.A. Following live-trapping sessions, we searched the forest floor
for truffle diggings...
'Golden Delicious' winter squash (GDWS), Cucurbita maxima Duchesne, provides significant amounts of pollen (24 mg) and nectar (236 μl), but with a low reward of 14% nectar sugar. The quantity of nectar produced per GDWS flower differed between sites and floral sex. The GDWS male flowers had 25% higher sugar...
We conducted capture and acoustic surveys for bats in six areas along a latitudinal gradient in Southeast Alaska from mid-May to September in 2005 and we continued surveys on Prince of Wales Island from mid-May to September in 2006. We determined the level of effort required to catch each species...
Partial migration is a common migratory behavior where some individuals in a population migrate and others do not. Patterns of partial migration can vary dramatically, especially for species that inhabit a wide range of environments. I described and predicted spatial variation in marine migration (anadromy) of female Oncorhynchus mykiss (steelhead...
Reforestation-based restoration of severely burnt plantations is one of the primary management activities following wildfire on U.S. federal lands. Restoration effects on early-seral plant and cryptogam communities have not been documented. The objectives of this study were, in severely burnt plantations two to four years post-fire, to examine the: (1)...
Three studies were conducted to evaluate different grazing systems on mixed conifer rangelands in eastern Oregon, and photo points and aerial photography was used to determine effects of 25 years of cattle grazing on stream channel changes and vegetation responses. The first study was designed to determine if grazing treatment...