Somewhat frequent in most of the counties indicated on the map and probably rare or absent in most of the remaining southern counties. Found on the crests and slopes of black and white oak ridges and in low ground in hard, white clay soil with sweet gum and beech.

Shrub or small tree to 12 m, the stem, branches, and often the petioles and lf-rachis armed with stout prickles; lvs to 1 m, twice or partly thrice compound, the rather firm lfls ovate, 4-10 cm, acute or acuminate, serrate, acute to broadly rounded at base; umbels very numerous in a terminal compound panicle; fr black; 2n=24. Moist or wet woods; Del. to s. Ind. and Mo., s. to Fla. and Tex., and intr. n. to N.Y., s. N. Engl., and Mich. June, July.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.