Family: Betulaceae, Birch view all from this family

Description Graceful tree with straight trunk, pointed or rounded crown, and mottled, light gray to whitish, smooth bark.
Height: 40-100' (12-30 m).
Diameter: 2 1/2' (0.8 m), sometimes larger.
Leaves: in 3 rows; 3-5" (7.5-13 cm) long, 1 3/4-3" (4.5-7.5 cm) wide. Ovate to elliptical, short-pointed at both ends, slightly thickened, wavy-lobed and doubly saw-toothed, edges slightly turned under, with 10-15 nearly straight parallel veins on each side. Dark green and usually hairless above, gray-green with rust-colored hairs beneath.
Bark: mottled light gray to whitish, smooth or becoming slightly scaly, thin; inner bark reddish-brown.
Twigs: slender, light green, covered with gray hairs when young, with 3-angled pith.
Flowers: tiny; in spring before leaves. Male yellowish, in drooping, narrowly cylindrical catkins 4-6" (10-15 cm) long, 1/4" (6 mm) wide. Female reddish, in narrow cones 3/8-1/2" (10-12 mm) long.
Cones: 1/2-1" (1.2-2.5 cm) long; 4-8 on short stalks, elliptical, with many hard black scales; remaining attached; tiny, rounded, flat nutlets with 2 narrow wings; maturing in late summer.

Habitat Moist soils including loam, gravel, sand, and clay, along streams and lower slopes; often in nearly pure stands.

Range SE. Alaska southeast to central California; also local in N. Idaho; to 2500' (762 m).

Discussion The leading hardwood in the Pacific Northwest, Red Alder is used for pulpwood, furniture, cabinetwork, and tool handles. It is planted as an ornamental in wet soils and is a pioneer on landslides, roadsides, and moist sites after logging or fire. Red Alder thickets are short-lived and serve as a cover for seedlings of the next coniferous forest. Alder roots, like those of legumes, often have swellings or root nodules containing nitrogen-fixing bacteria, which enrich the soil by converting nitrogen from the air into chemicals like fertilizers that the plants can use. The common name describes the reddish-brown inner bark and heartwood.