Cascade barberry, botanical name mahonia nervosa, is a flowering plant native to the northwest coast of North America.
It is also known as dwarf Oregon-grape, Cascade Oregon-grape, or dull Oregon-grape.
The leaves are opposite arranged compound leaves, numbered in strands of 9 to 19. Each leaflet is strongly toothed and slightly shiny.
Its scientific name "nervosa" is due to the leaflets with not one central vein, but multiple veins arranged in a fan-like pattern branching from the base of the leaflet.
A variety of small mammals, especially white-footed rats on the Oregon Coast Range, like to eat the leaves of this plant.
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