Flora of North America species comparison

perennial, climbing, branching, terete, to 7+ m × 9 mm, woody, glabrous, with prickles proximally, prickles usually absent distally;

prickles blackish, unequal, 3–10+ mm, bristly, flexible.

perennial, climbing or not, to 12 m, woody, glabrous;

prickles sometimes absent distally, bristlelike, 3–11 mm, flexible.

± persistent in southern part of range, deciduous in north;

petiole 1–2 cm;

blade green, drying to light olive-gray, ovate-lanceolate, ovate, or sometimes pandurate, prominently reticulate, thin, 5–13 × 3–10 cm, not glaucous, glabrous (to prickly on major veins abaxially), base rounded to cordate, margins entire apically, minutely serrulate basally, thin, flat, not banded, not lobed, apex pointed.

evergreen, ± evenly dispersed;

petiole 0.5–2 cm;

blade dull green, drying to dull, ashy green, ovate to broadly ovate, conspicuously veined, 4–11 × 3–8 cm, not glaucous, glabrous, base cordate to subcordate;

margins entire, thin, flat, not banded, never lobed;

apex acute, often apiculate.

many, axillary to leaves, to 25-flowered, open to dense, spherical;

peduncle often drooping, 1.5–6.5 cm.

axillary to distal leaves, (2–)8–13(–19)-flowered;

peduncle 2–5 cm, longer than petiole of subtending leaf.

perianth green to bronze;

tepals 4–5 mm;

anthers ± equaling to shorter than filaments;

ovule 1 per locule;

pedicel 0.4–1.2 cm.

perianth green;

tepals 3–6 mm;

ovule 1 per locule;

pedicel thin, 1–1.5 cm.

black, globose, 6–10 mm, not glaucous.

black, ovoid, 7–9 mm.

;

rhizomes knotty, short.