An investigation was conducted in 1980 and 1981 on the larval
parasitoid complex of the orange tortrix, Argyrotaenia citrana
(Fern.), a major contaminant in cane fruits (Rubus spp.) in the
Pacific Northwest. A total of 13 parasitoid species were reared from
1,350 larvae predominantly collected from red raspberries in western...
The identity and distribution of ant species preying on the
western spruce budworm (Choristoneura occidentalis Freeman) was
investigated in eastern Oregon and western Montana. A sticky trap was
developed to index ant foraging activity in the canopy by intercepting
ants falling from the tree as they traveled between canopy and...
The Macrocheles glaber species group contains many
of the common mites which are associated with the dung
of domestic animals. Species in the glaber group have
been investigated for their use as biological control
agents of synanthropic flies.
Over 10,000 slide-mounted specimens of Macrocheles
in the OSU Acarology Collection and...
In recent years, red raspberry production in Washington and British Columbia has been severely limited by a newly emerged virus complex that causes symptoms of crumbly fruit. The complex is comprised of three viruses: Raspberry bushy dwarf virus (RBDV), Raspberry leaf mottle virus (RLMV) and Raspberry latent virus (RpLV). Both...
The European hazelnut, Corylus avellana L., was imported into the U.S. in the late 1800's and is now grown throughout the Willamette Valley in Oregon. A native species of hazelnut, C. cornuta Marshall, is a common shrub found in forested areas of the Pacific Northwest. Foliage of both C. avellana...
Metals are a persistent form of freshwater pollution and have been shown to bioaccumulate in aquatic macroinvertebrates through direct contact with contaminated water, sediments, and through consumption of contaminated organisms. This research explored the longitudinal bioaccumulation patterns of 5 common trace metals (Cr, Cu, Zn, Cd, and Pb) in the...
Edge effects resulting from forest fragmentation are likely to alter the distributions and
interactions of resident species. I evaluated changes in species composition, species
turnover, and relative abundance of ground arthropods across replicated transects
extending from regenerating clearcuts into old-growth Douglas-fir forests. Arthropods
were collected from 3-August to 14-September in...
The effect of anthropogenic disturbance on river systems is gaining attention, and concerns about the state of freshwater natural resources are increasing globally, as are efforts to restore habitat that has been degraded by disturbance. In rivers, non-point source pollution affects the physical characteristics of the habitat and the endemic...
Cereal crops cultivated in Mali, Mauritania and Senegal consist
primarily of sorghum, millet, rice and maize. They form the gramineous
crops that, are programmed for the agricultural improvement of
the Senegal River Basin. Twelve economically important insect pests
on these crops were selected for study and treated with regard to...