red alder

tree

Also known as: Alnus oregona, Alnus rubra

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Last updated

July 13, 2026

Quick Summary

Red alder (Alnus rubra) is a tree species native to the Pacific coast of North America. It is a member of the alder genus (Alnus), which includes about 30 species of shrubs and trees distributed throughout the Northern Hemisphere and parts of South America. Alders are known for their ability to fix atmospheric nitrogen, which helps enrich soil and prepare it for other trees. The wood of the red alder is hard and red, and it is commonly used for furniture, cabinetry, and millwork. Alders are also planted to prevent erosion and control flooding due to their extensive root systems and tolerance for wet soils.123

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alder
Major species
…North American alders are the red alder (Alnus rubra), a tall tree whose leaves have rusty hairs on their lower surfaces; the white, or Sierra, alder (A. rhombifolia), an early-flowering tree with orange-red twigs and buds; the gray, or speckled, alder (A. incana), a small shrubby tree, often with conspicuous…
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…North American alders are the red alder (Alnus rubra), a tall tree whose leaves have rusty hairs on their lower surfaces; the white, or Sierra, alder (A. rhombifolia), an early-flowering tree with orange-red twigs and buds; the gray, or speckled, alder (A. incana), a small shrubby tree, often with conspicuous…
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