Maple, Boxelder

Acer negundo is a small, usually fast-growing and fairly short-lived tree that grows up to 33–82 ft tall, with a trunk diameter of 12–20 in, rarely greater than 3 ft, in diameter. It often has several trunks and can form impenetrable thickets.

This species prefers bright sunlight. It often grows on flood plains and other disturbed areas with ample water supply, such as riparian habitats. Human influence has greatly favored this species; it grows around houses and in hedges, as well as on disturbed ground and vacant lots.

Unlike most other maples (which usually have simple, palmately lobed leaves), Acer negundo has pinnately compound LEAVES that usually have three to seven LEAFLETS Simple leaves are also occasionally present; technically, these are single-leaflet COMPOUND LEAVES. The leaflets are about 2–4 in long and 1–3 in wide with slightly serrate margins. Leaves have a translucent light green color and turn yellow in the fall.

The FLOWERS are small and appear in early spring on drooping racemes 4–8 in long. The SEEDS are paired samaras, each seed slender, 0.4–0.8 in long, with a 0.8–1.2 in incurved wing; they drop in autumn or they may persist through winter. Seeds are usually both prolific and fertile.

Unlike most other maples, A. negundo is fully dioecious and both a “male” and “female” tree are needed for either to reproduce.

FRUIT: Maple keys, full size in early summer. Borne in drooping racemes, pedicels one to two inches long. Key an inch and a half to two inches long, nutlets diverging, wings straight or incurved. September: Seed half an inch long. Cotyledons, thin, narrow.

The SHOOTS are green, often with a whitish to pink or violet waxy coating when young. BRANCHES are smooth, somewhat brittle, and tend to retain a fresh green color rather than forming a bark of dead, protective tissue. The BARK on its trunks is pale gray or light brown, deeply cleft into broad ridges, and scaly.

Although its light, close-grained, soft WOOD is considered undesirable for most uses, this tree has been considered as a commercial source of wood fiber, for use in fiberboard

Several birds and some squirrels feed on the seeds. The Evening Grosbeak uses them extensively. The Maple Bug (also known as the Boxelder Bug) lays its eggs on all maples, but prefers this species.