Riparian trees,shrubs, and forest regeneration in the coastal mountains of Oregon

Riparian trees and shrubs are important providers of shade, bank stability, and woody debris needed for optimal stream quality and fish habitat in the coastal mountains of Oregon, but more data are needed to relate this woody vegetation to environmental variables. Trees, shrubs, and forest regeneration were studied in 22 riparian environments to provide those data. Conifer basal area increased with elevation, stream gradient, time since disturbance, and distance from the stream; it decreased with stream width. Salmonberry (Rubus spectabilis Pursh) cover and stink currant (Ribes bracteosum Dougl. ex Hook.) cover were highest near the streams. Dwarf Oregon grape (Berberis nervosa Pursh) cover and salal (Gaultheria shallon Pursh) cover were lowest near the streams. Although forest regeneration was poor everywhere, it decreased with total shrub cover and increased with stream gradient. Existing riparian conifer stands should be maintained wherever a continuing supply of coarse woody debris is required.