A field study was established to determine the impact of interfering vegetation on survival and growth of Engelmann spruce (Piceaeigelmannii Parry) and lodgepole pine (Pinus contorta var contorta Dougi.) at a site in the high elevation Engelmann spruce-Subalpine fir (ESSF) zone, of south-central British Columbia. The study examined (1) the...
Site 35JA42 represents the first protohistoric village
complex excavated in Southwest Oregon. Analyses of animal
bones recovered from the site offer the first significant
insights into human subsistence behaviors in this region.
Although the faunal assemblage is extremely fragmented,
detailed zooarchaeological analysis indicates that deer were
the primary meat resource...
The causes of natural mortality and disease in free ranging black bears, Ursus americanus, in California, Oregon, and Washington are poorly known. Life history components, such as scavenging and overlapping habitat with many species of carnivores, potentially expose bears to a wide range of infectious disease agents. To date, no...
Leaf surface area present on black cottonwood (Populus trichocarpa) and Douglas hawthorn (Crataegus douglasi) was measured indirectly using a point frame, photographs, and a canopy analyzer. Each was compared to directly measured leaf surface area. Six black cottonwood and 3 Douglas hawthorn shrubs were selected in 1996 and 9 black...
Pastures consisting of mixtures of subclover (Trifolium
subterraneum) and grasses have responded to sulfur fertilization
on many sites in Douglas County, Oregon. The objectives of this
study were to examine specific changes in forage quality which occur
as sulfur is applied in excess of the amount required for maximum
yield...
Vital rates and population connectivity are fundamental concepts in animal ecology and such information is critical for successful conservation planning. The Black-backed Woodpecker (Picoides arcticus) is a species of conservation concern because of its strong association with forests recently burned by high-severity wildfire. However, several recent studies have found that...
As a key factor contributing to slope stability, in-stream habitat for aquatic species (e.g., salmonids), nutrient cycling, and corridors for upland species, riparian vegetation and its maintenance is of critical conservation importance. Subsequently, the chronic degradation of aquatic and riparian ecosystems in the semi-arid and arid landscapes of the western...
The black vine weevil (BVW), Otiorhynchus sulcatus (F.) (Coleoptera:
Curculionidae) is a persistent pest of nursery operations in the United States,
feeding on over 140 species of plants. The goals of this research were to 1) assess
the behavioral response of BVW to a commonly employed insecticide bifenthrin
(Talstar 0.2G®)...
The rip current field resulting from the transformation of surface gravity waves over offshore submarine canyons is studied. Employing a wave transformation model and a wave-induced circulation model over observed bathymetry we find that rip current circulation cells exist with alongshore spacing of O(1OOm) even though the nearshore bathymetry displayed...