Red Alder

Alnus rubra

Plant Description

Red alder is a fast-growing deciduous tree native to moist lowlands, riparian zones, and coastal forests of the Pacific Northwest. It typically reaches 50–120 feet tall with smooth gray bark and broadly ovate, serrated leaves. In early spring it produces long, drooping catkins, followed by small, woody cone-like fruits that persist into winter. In autumn, leaves provide brilliant color. As a nitrogen-fixing species, red alder enriches soils and plays a key role in forest succession, quickly colonizing disturbed sites and preparing the way for longer-lived conifers. Ecologically, it it is an early-successional species that moves in after disturbance and prepares the ground for late-successional trees to get established. Red alder also provides shade for streams, improving fish habitat while offering food and habitat for a wide range of birds, insects, and mammals like deer, elk, and beaver. It is quick-growing and tolerant of a wide range of conditions including full sun to full shade and seasonal inundation. The wood is prized for furniture and cabinetry, and the bark for dye and medicine.

Plant Details

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