Flora of North America species comparison

gray, deeply furrowed, warty with age.

usually gray, smooth or often fissured and conspicuously warty.

without thorns, spreading, young branches mostly pubescent.

without or with thorns, slender, glabrous or pubescent.

blade lance-ovate to broadly ovate or deltate, 5-12 × 3-6(-9) cm (on fertile branches), leathery, base oblique or obliquely somewhat acuminate, margins conspicuously serrate to well below middle, teeth 10-40, apex acuminate;

surfaces scabrous.

blade deltate to ovate to oblong-lanceolate, base oblique or cuneate to rounded, margins entire or serrate-dentate;

venation 3(-5)-pinnate.

dense pendulous clusters.

staminate inflorescences cymes or fascicles; pistillate solitary or few-flowered clusters.

usually unisexual, staminate and pistillate on same plants, along with a few bisexual flowers, pedicellate on branches of current year, appearing in mid or late spring.

filaments incurved in bud, exserted after anthesis;

gynoecium minute, rudimentary.

calyx slightly to deeply 4(-5)-lobed;

stamens 4-5, inserted on pilose receptacle, included, often nonfunctional filaments usually shorter than in staminate flowers, rarely absent;

anthers ovate, face to face in bud, extrorse;

ovaries sessile, ovoid, 1-locular;

styles short, sessile, divided into 2 divergent, elongate, reflexed lobes, lobes entire or 2-cleft.

fleshy drupes, ovoid or globose;

outer mesocarp thick, firm, inner mesocarp thin, fleshy;

stones thick walled, ripening in autumn, persisting after leaves fall.

dark orange to purple- or blue-black when ripe, orbicular, to 7-11(-20) mm diam., commonly with thick beak;

pedicel to 15 mm.

light yellow, weak.

cream colored, 7-9 × 5-8 mm, reticulate.

= 10.

= 20, 30, and 40.