Herb up to 1 m. tall; branches decumbent and rooting at base, then erect, up to 1 m. tall, up to 1 cm. diam., subsucculent. Young branchlets, petioles and infl.-axes with sparse hairs or glab.; stinging hairs few. Lvs 10-15 × 8-14 cm., on stout petioles up to 5 cm. long; lamina broadly ovate-cordate to suborbicular, acute or obtuse, coarsely dentate-serrate, almost free of stinging hairs; sts a lateral pair of lflts developed on petiole; teeth up to 1 cm. long, sinus acute. Stipules lanceolate, up to 2 cm. long, us. bifid. Staminate infl. of 1-3 branched spikes up to 7 cm. long, per. glabrate; pistillate similar, fls densely arranged, per. glabrate. Achenes elliptic in outline, 1·5-2 mm. long, pale brown.

2n = 24

Stout, monoecious herb, usually with few short-stalked stinging hairs, otherwise sparsely to densely hairy; branches decumbent and rooting, then erect. Lvs broadly ovate, acute, cordate to truncate at base, coarsely serrate, 10-20 cm long. Stipules 2 per node and 2-fid, or 4 per node and entire. Most racemes unisexual; ♀ racemes above ♂ on stem.