Alternate name: Black Alder, European Black Alder

Family: Betulaceae, Birch view all from this family

Description Introduced. Large tree with rounded or oblong crown and gummy twigs and foliage.
Height: 50-70' (15-21 m).
Diameter: 1-2' (0.3-0.6 m).
Leaves: in 3 rows; 1 1/2-4" (4-10 cm) long, 1-2 1/2" (2.5-6 cm) wide. Elliptical to nearly round; doubly saw-toothed (also lobed in cultivated varieties); with 5-7 parallel veins on each side; gummy when young. Shiny dark green above, light green with tufts of rusty hairs beneath, remaining green and shedding late.
Bark: brown, smooth becoming furrowed into broad plates.
Twigs: mostly hairless; very gummy when young; with 3-angled pith.
Flowers: tiny; in early spring before leaves. Male in catkins 1-1 1/2" (2.5-4 cm) long; upright and later drooping. Female in cones 1/4" (6 mm) long.
Cones: 5/8-7/8" (15-22 mm) long; in clusters of 3-5; complete or egg-shaped, black, hard, gummy, long-stalked; remaining attached. Nutlets rounded, nearly 1/8" (3 mm) long, flattened.

Habitat Wet soils in humid, cool temperate regions.

Range Native of Europe, N. Africa, and Asia. Naturalized locally in SE. Canada and NE. United States.

Discussion The Latin species name, meaning "gummy" or "gluey," describes the young twigs and leaves. This alder was introduced in colonial times and planted for shade and ornament. It is considered an invasive alien plant in some areas.