Flora of North America species comparison

biennial, initially low-arching, then falling and creeping (or climbing through other vegetation), glabrous or moderately hairy, sparsely to densely short- to long-stipitate-glandular, not pruinose;

prickles moderate to dense, recurved, sometimes distally slender, 1–4 mm, broad-based;

bristles absent or sparse to dense, erect to retrorse, red to purple, rarely green, slender, weak, gland-tipped.

biennial, creeping, glabrous, eglandular, strongly pruinose;

prickles sparse, erect or slightly curved, weak, slender, 2–3 mm, narrow-based.

persistent or semipersistent, ternate to palmately compound, lustrous;

stipules filiform, linear, or lanceolate, 2–12(–15) mm;

leaflets 3–5, terminal narrowly elliptic or ovate to obovate, 2–8.5 × 0.7–4.5 cm, base rounded to cuneate, unlobed, margins moderately to coarsely serrate to doubly serrate, apex acute to acuminate, abaxial surfaces with hooked prickles on midvein, glabrous or sparsely to moderately hairy, eglandular or sparsely short-stipitate-glandular along central vein.

deciduous, ternate;

stipules filiform to linear, 3–10 mm;

terminal leaflets ovate to elliptic, 4–8 × 3–7 cm, base tapered or subcordate, often 2-lobed, margins coarsely dentate, apex acute to rounded, abaxial surfaces unarmed, densely white-tomentose, eglandular.

terminal on short shoots, usually appearing axillary, 1(–3)-flowered.

terminal and axillary, (1–)2–4(–10)-flowered, cymiform.

prickles and, often, bristles moderate to dense, recurved, moderately to densely hairy, sparsely to moderately sessile- to short-stipitate-glandular.

unarmed, finely hairy, stipitate-glandular.

bisexual;

petals white to pink, elliptic to obovate, 10–16(–25) mm;

filaments filiform;

ovaries glabrous.

bisexual;

petals white, oblong to oblanceolate, 4–8 mm;

filaments laminar;

ovaries white-tomentose.

black, globose to ovoid, 1–1.5(–2) cm;

drupelets 10–50, strongly coherent, separating with torus attached.

reddish purple, hemispheric to conic, 0.4–1 cm diam.;

drupelets 10–40, coherent, separating from torus.

= 14.