With legislation to protect wetlands and current pressures to convert them to other uses, it is often necessary to accurately determine a wetland-upland boundary. We investigated 6 methods to establish such a boundary based on vegetation. Each method was applied to a common data set obtained from 295 quadrats along...
Waldo Lake, located in the Oregon Cascades, is
considered to be one of the most dilute lakes in the
world. Even with very low nutrient concentrations and
sparse populations of zooplankton, introduced fish in the
lake are large in size and in good condition when compared
to fish from other...
Currently, the Port of Portland is developing a 9, 410 acre area
at the confluence of the Columbia and Willamette Rivers in Multnomah
County, Oregon. This area will be developed for industrial, commercial,
and recreational use. The recreational development in the
North Portland Peninsula area, including the Rivergate Industrial
District,...
Continental flood basalts represent short-lived but immense blasts of mafic magma to the continental crust. The youngest and smallest continental flood basalt worldwide, the Columbia River Basalt, initiated with the eruption of the most mafic member, the Steens Basalt (~16.9 Ma). The Steens Basalt is exposed in southeast Oregon, southwest...
This classification lists the native plant associations known to occur in Oregon, and includes both successional and climax vegetation types that were an important part of the presettlement landscape of Oregon. It serves as an index to the diversity, distribution and relative rarity of the state's native plant associations, and...
This classification is an update of the 2004 classification of native vegetation of Oregon by Kagan, Christy, Murray and Titus. As before, this classification lists the native plant associations known to occur in Oregon, and includes both successional and climax vegetation types that were part of the presettlement landscape of...
Vegetation ecology of eight Oregon freshwater wetlands was
described and net aerial primary productivity estimated in four
wetlands. Plant cover samples were used to classify 37 wetland and
11 terrestrial communities by agglomerative hierarchical clustering.
Samples and species were ordinated. Direct measurements were made
of sample relative elevation, inundation duration,...
This guide provides keys, descriptions, and stand tables for 122 native freshwater plant associations (14 forest and woodland, 28 shrub, 78 herbaceous, 2 nonvascular) in northwestern Oregon, based on analysis of data from 1,992 plots distributed throughout the study area. Descriptions are provided for eight other plant associations for which...