November 6, 1805, along the Cowlitz River, Washington.
Medium to large tree with tall, straight trunk and open, rounded crown; showy in winter with long, golden-colored male catkins hanging from slender, leafless twigs. Height: 70 ft (21 m). Diameter: 2 ft (0.6 m).
With chaparral and Ponderosa pine in foothill woodlands.
Western Idaho and Washington south in mountains to western Nevada and southern California; at 100-8,000 ft (30-2,438 m); generally below 5,000 ft (1,524 m).
White alder, named for its pale green foliage, is the only alder native in southern California. Limited to permanent streams, it is a good indicator of water.