Climbing to 30 m; young shoots and infl densely covered with small stellate to peltate hairs; lvs shining, dark green, dimorphic, those of flowering shoots narrowly elliptic to suborbicular-cordate, entire, the others broad, palmately 3- or 5-lobed; fr nearly black, with 2 or 3 pyrenes; 2n=48. Native of Europe, cult. in various forms and occasionally escaped, especially southward.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.