Astragalus diaphanus is a rare plant endemic to the
John Day River drainage of north-central Oregon. This
species has several interesting features, including the
dimorphism of its fruit and its geographical isolation from
the two nearest taxonomically related species, which occur
in Colorado. This study addressed the species' distribution
and...
The purpose of this study was to determine plant species composition, community structure, successional relationships, vegetational development and plant distributions in estuarine salt marshes on the Pacific Coast of Oregon.
Quadrat and transect samples of plant presence and cover, collected from April 1971 - June 1974, were subjected to phytosociological...
The seasonal duration of snow cover is a primary factor influencing the patterns of vegetation in high subalpine and alpine environments, but little is known concerning the responses of plant reproduction and
seedling recruitment to gradients of snow-release. Vegetation patterns of a high subalpine site in the Oregon High Cascades...
Growth and replacement patterns of four successionally important
species occurring on Douglas fir clear-cuts were investigated
from September 1964 to June 1967. The study was carried out
on the Marys Peak watershed located near Corvallis, Oregon.
Species used in the study include Holcus lanatus, Senecio
jacobaea, Lotus crassifolius var. subglaber,...
I studied the water relations traits, twig conductivity, C'3 isotopic composition,
and wood density of three conifer and five angiosperm species in western Oregon. This
study took place from spring 2002 to fall 2003 on four sites. Species were selected to
represent the diversity of drought tolerance of woody plants...
With little previous research on Astragalus peckii (Fabaceae), a state-listed
Threatened species in Oregon, I investigated three facets of its biology which are
integral to the conservation and management of the species. First, a four-year
demographic study of two large populations revealed increasing population growth at
one site (Chiloquin) and...
Soil moisture depletion trends under five plant species growing
on the clear-cuts of the Marys Peak Watershed near Corvallis,
Oregon, were followed during the summers of 1963 and 1964. The
species were Holcus lanatus, Lotus crassifolius var. subglaber,
Gaultheria shallon, Berberis nervosa, and Acer circinatum; and
were dominant plants of...