Rather stout dioec. herb up to 4 dm. tall, somewhat woody at the base, spreading by well-developed rhizomes. Stems, branches petioles and lvs (except in shade) especially when young, densely clad in stiff stinging hairs. Lvs 2-4 × 1-4 cm., on petioles up to 4 cm. long (shade lvs often larger); lamina subcoriac., broad-ovate, subcordate to truncate or rarely cuneate at base, obtusely to acutely dentate; teeth c. 5 mm. long, sinus acute. Stipules up to 1 cm. long, us. entire. Spikes up to 5 cm. long; per.-segs glabrate; staminate with scattered clusters of fls; pistillate with approximate clusters. Achenes 1-1·5 mm. long, stigmas prominent.

2n = 24

Stout, erect or decumbent, dioecious herb, with numerous very shortly stalked stinging hairs, otherwise sparsely hairy. Lvs ovate to elliptic, acute, obtuse to truncate or rarely subcordate at base, serrate, 3-7 cm long. Stipules 4 per node, entire.