HABIT.—A medium-sized tree 30-50 feet high, with a trunk diameter of 1-2 feet; stout, upright branches and slender branchlets form a compact, broad, irregular crown.
LEAVES.—Opposite, pinnately compound, 10-12 inches long. Leaflets 7-9, 3-5 inches long, 1-1-1/2 inches broad; short-stalked; oblong-lanceolate to ovate; slightly serrate or entire; thin and firm; glabrous, yellow-green above, pale and silky-downy beneath. Petioles stout, pubescent.
FLOWERS.—May, with the leaves; dioecious; borne in compact, downy panicles on shoots of the previous season; calyx cup-shaped, 4-toothed; corolla 0; stamens 2, rarely 3; ovary 2-celled.
FRUIT.—Early autumn, persistent on the branches throughout the winter; samaras 1-2 inches long, in open, paniculate clusters.
WINTER-BUDS.—Small, rounded; bud-scales rounded on the back, 3 pairs, rusty-brown, tomentose.
BARK.—Twigs pale-pubescent at first, lasting 2-3 years or often disappearing during the first summer, finally ashy gray or brownish and often covered with a glaucous bloom; brown or dark gray on the trunk, with many longitudinal, shallow furrows; somewhat scaly.
WOOD.—Heavy, hard, strong, brittle, coarse-grained, light brown, with thick, yellow-streaked sapwood.
DISTRIBUTION.—Not a common tree. Most frequent in the southern half of the Lower Peninsula, but has been reported further north, i.e., Drummond’s Island and Keweenaw County, Upper Peninsula.
HABITAT.—Prefers wet or moist, rich loam; river-banks; swampy lowlands.
NOTES.—A rapid grower in youth. Fairly immune from insect and fungous diseases.