Alternate name: Western Balsam Poplar, California Poplar

Family: Salicaceae, Willow view all from this family

Description The tallest native cottonwood, with open crown of erect branches and sticky, resinous buds with balsam odor.
Height: 60-120' (18-37 m).
Diameter: 1-3' (0.3-0.9 m), sometimes much larger.
Leaves: 3-6" (7.5-15 cm) long, 2-4" (5-10 cm) wide, larger on young twigs. Broadly ovate; short- or long-pointed at tip, rounded or slightly notched at base; finely wavy-toothed, slightly thickened, hairless or nearly so. Shiny dark green above, whitish and often with rusty veins beneath; turning yellow in autumn. Leafstalks slender, round, hairy.
Bark: gray, smooth, becoming thick and deeply furrowed into flat, scaly ridges.
Twigs: brownish, stout, often hairy when young.
Flowers: catkins 1 1/2-3 1/4" (4-8 cm) long; reddish-purple; male and female on separate trees; in early spring.
Fruit: 1/4" (6 mm) in diameter; round capsules, light brown, hairy; maturing in spring, splitting into 3 parts; many cottony seeds.

Habitat Moist to wet soils of valleys, mainly on stream banks and flood plains, also on upland slopes; often in pure stands and with willows and Red Alder.

Range S. Alaska south to S. California and east in mountains to extreme SW. Alberta and Montana; also local in SW. North Dakota and N. Baja California; to 2000' (610 m) in north; to 9000' (2743 m) in south.

Discussion Black Cottonwood, formerly considered the species P. trichocarpa but now designated a subspecies of Balsam Poplar, is the tallest native western hardwood. The current champion in Yamhill County, Oregon, measures 147' (44.8 m) in height, 30.2' (9.2 m) in trunk circumference, and 97' (29.6 m) in crown spread. The wood is used for boxes and crates, pulpwood, and excelsior. Black Cottonwood intergrades with its northern relative Balsam Poplar where both meet in southern Alaska and elsewhere.