Tall shrub or clumped small tree to 10 m; winter-buds with 2-4 valvate scales; lvs 3-lobed or obscurely 5-lobed, softly hairy beneath, coarsely and irregularly serrate, the teeth 2-3 per cm, each tipped with a minute sharp gland; fls in fascicles of 2-4 along an erect axis, forming a slender, terminal, long-peduncled panicle 3-8 cm, long-pediceled, the terminal one of each fascicle usually perfect, the others sterile; pet greenish, very narrowly linear-oblanceolate, 3 mm, much exceeding the sep; disk extrastaminal; style barely notched; mericarps 1.8-2.5 cm, conspicuously reticulate over the seed, the wings diverging at about a right angle; 2n=26. Moist woods; Nf. to Sask., s. to Conn., Pa., O. and ne. Io., and in the mts. to N.C. and Tenn. June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.