Mixed Needleleaf-Broadleaf Forest Zone Complex
A highly intricate set of zones closely related to plant communities in California, this mixed evergreen forest straddles the Siskiyou Mountains in southwestern Oregon. Edaphic, fire history, and climatic contrasts lead to sharp breaks in plant cover. Douglas-fir dominates the upper canopy, but various sclerophyllous trees and shrubs are found in the understory including tanoak (Lithocarpus densiflorus), canyon live oak (Quercus chrysolepis), Pacific madrone (Arbutus menziesii), and golden chinquapin (Castanopsis chrysophylla). Serpentine soil bears a distinctive flora and sparse vegetation, and other dry rocky areas support sclerophyllous broadleaf chaparral.