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, prostrate to clambering, branching, slender, to 1 m, ± woody, densely woolly-pubescent, usually prickly (especially at base).

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.

mostly evergreen, ± evenly disposed;

petiole 0.05–0.25 cm, often longer on sterile shoots;

blade gray-green, drying to ashy gray-green, obovate to ovate-lanceolate, with 3 prominent veins, 6–10.5 × 5–8 cm, glabrous adaxially, densely puberulent abaxially, base cordate to deeply notched, margins entire, apex bluntly pointed.

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

peduncle 0.2–1.5 cm.

1–7, axillary to leaves, 5–16-flowered, loose, spherical;

peduncle 0.2–0.8 cm, shorter than to 1.5 as long as petiole of subtending leaf.

perianth green;

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

ovule 1 per locule;

pedicel 0.2–1 cm.

perianth yellowish;

tepals 3–4 mm;

anthers much shorter than filaments;

ovule 1 per locule;

pedicel thin, 0.1–0.4 cm.

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

red, ovoid, 5–8 mm, with acute beaks, not glaucous.

;

rhizomes linear or dense masses of potatolike tubers.