Flora of North America species comparison

perennial, climbing, branching zigzag, terete, 5–9 m × 5–8 mm, woody, glabrous;

prickles numerous, sparse or absent distally, flattened, rigid, stout, to 4 mm.

perennial, climbing, branching, terete, 5+ m × 15 mm, woody, glaucous, glabrous;

prickles dark, flat, to 12 mm, rigid.

evergreen;

petiole 0.5–1.2 cm;

blade green abaxially, drying to brownish green, narrowly ovate to ovate-elliptic, with 3 prominent veins, secondary veins obscure to prominent, 4.5–6(–8.5) × 2–3.5 cm, not glaucous, glabrous or minutely pubescent abaxially, base auriculate, pandurate, or rounded, cuneate at insertion of petiole, margins entire, apex acute to abruptly deflexed point.

evergreen, ± evenly arranged;

petiole 0.5–1.5 cm;

blade abaxially green, drying to pale brown to brownish green, oblong-elliptic, lance-elliptic, or, sometimes, linear or broadly ovate, not prominently reticulate, 3-veined from base, 7–13 × 1.3–4(–6) cm, coriaceous, not glaucous, glabrous or minutely pubescent abaxially, base attenuate to rounded;

margins entire, often revolute, teeth absent;

apex acute to rounded, often mucronate.

3–8, terminal, axillary to leaves, 5–8(–25)-flowered, loose;

peduncle 0.2–1.5 cm.

numerous, axillary to leaves, generally on short branches, 5–12(–25)-flowered, ± open, spherical;

peduncle 0.5–1.5 cm, shorter than subtending leaf.

perianth green;

tepals: staminate 6–8 mm, pistillate 3–4 mm;

ovule 1 per locule;

pedicel 0.2–1 cm.

perianth yellow, cream, or white;

tepals 4–5 mm;

anthers exceeding filaments;

ovule 1 per locule;

pedicel 0.5-1 cm.

purplish maroon, purple, or black, ovoid to flattened, 5–7 mm, glaucous.

black, ovoid, 5–8 mm, shining, glaucous.

;

rhizomes linear or dense masses of potatolike tubers.

forming extensive colonies;

rhizomes irregularly branched, tuberous, woody.