Flora of North America species comparison

scrambling to climbing, 3-4 m. Leaf blade 3-foliolate;

leaflets ovate, largest leaflets usually 3-lobed, 1.5-6 × 1.5-5 cm;

terminal leaflet occasionally 3-cleft, margins usually toothed;

surfaces glabrous or sparsely silky.

blade undivided or 1-3-pinnately or -ternately compound;

leaf or leaflets cordate to orbiculate, oblong, lanceolate, or oblanceolate, lobed or unlobed, margins entire or toothed.

axillary, flowers solitary, rarely 3-flowered cymes.

axillary and/or terminal, 1-many-flowered cymes or panicles or flowers solitary or in fascicles, to 15 cm;

bracts present and leaflike or ± scalelike or absent, not forming involucre.

unisexual;

pedicel (including peduncle) stout, 3.5-11 cm;

sepals wide-spreading, not recurved, white to cream, ovate or elliptic to obovate or oblanceolate, 10-21 mm, abaxially and adaxially pilose;

stamens 50-100;

filaments glabrous;

staminodes absent or 50-100;

pistils 75-100.

bisexual or unisexual, radially symmetric;

sepals not persistent in fruit, 4, white, blue, violet, red, yellow, or greenish, plane, ovate to obovate or linear, 6-60 mm;

petals absent;

sometimes anther-bearing staminodes between sepals and stamens;

stamens many;

filaments filiform to flattened;

pistils 5-150, simple;

ovule 1 per pistil;

beak present.

achenes, aggregate, sessile, lenticular, nearly terete, or flattened-ellipsoid, sides not prominently veined;

beak terminal, straight or curved, 12-110 mm.

asymmetric-ovate, not broadly orbiculate, 3-4 × 1.5-2 mm, not conspicuously rimmed, glabrous;

beak 3.5-5.5 cm.

, ± woody, sometimes only at base, climbing by means of tendril-like petioles and leaf rachises, or erect, herbaceous perennials, from elongate rhizomes.

= 8.

= 16.