The shallow water benthic habitat of the SW Beaufort Sea is frequently
gouged by the keels of ice pressure ridges. This natural physical
disturbance was hypothesized to be an important factor affecting the
structure of the benthic community. Smith-McIntyre grab samples were
taken from three discrete gouge axes and from...
Partly laminated sediments on the upper continental
slope (200-600 m) off central Peru contain a diverse assemblage
of fish debris, diatoms, and the remains of a variety
of other nektonic, planktic, and benthic organisms. Approximately
97 percent of the fish scales recovered from
the best preserved cores come from the...
This work examined the importance of structural complexity of habitat, availability
of prey, and competition with ants as factors influencing the abundance and community
composition of arboreal spiders in western Oregon.
In 1993, I compared the spider communities of several host-tree species which
have different branch structure. I also assessed...
A parasitic wasp, Trioxys pallidus Haliday
(Hymenoptera: Aphidiidae) was imported from Europe and
initially released against the filbert aphid Mvzocallis
coryli (Goetze) in hazelnut (filbert) orchards of the
Willamette Valley, Oregon beginning in 1984. In the
present study, I investigated the establishment rates of
this parasitoid. A total of 13...
The probing behavior and feeding activity of green peach aphid, Myzus persicae
Sulzer, on Bacillus thuringiensis ssp. tenebrionis- transgenic potatoes, insecticide
treated potatoes, and host plants with different preference were electronically
monitored. I found that first, transgenic potatoes had no effect on green peach aphid
probing suggesting that transmission of...
A systematic study of the subfamily Dicyphinae Reuter (Heteroptera: Hiridae) resulted in a redefinition of the subfamily and included genera) and a revision of the
genus Dicyphus Fieber in the Western Hemisphere. The study entailed examination of about 14,000 specimens, including numerous noudicyphine, cimicomorphan taxa to assess character transformations. New...
Although science is widely accepted as a fundamental source of information underlying decisions about forest management and conservation, considerably less attention has been paid to the inevitable role that normative values and beliefs play in such decisions. This thesis highlights the normative dimensions of "ecological forestry," a strategy of forest...
Field and greenhouse experiments were conducted to determine the suitability of using incinerated sewage sludge ash as a soil amendment for sweet corn production on Willamette silt loam. In 1977, field plots were treated with 0, 11, 22, and 43 mt/ha of ash containing lime, in factorial combination with a...