Flora of North America species comparison

brown tinged with red or yellow, thin, shallowly furrowed, with long, narrow ridges.

gray-brown with orange tint, furrows shallow, ridges flat, broad.

orange-brown or dark green with reddish cast, pubescent or occasionally glabrous;

lenticels reddish brown, elliptic, prominent.

red-brown to light greenish brown, glabrous or with a few trichomes;

lenticels light colored, elliptic, prominent.

ovoid, 4-6 mm, apex acute to rounded;

outer scales yellow-brown with dark margins, glabrous or with a few marginal trichomes;

leaf scars half round, bundle scars numerous, in circle.

ovoid, slightly compressed, 3-7 mm, apex acute;

outer scales dark brown, often pubescent and minutely ciliate;

leaf scars oval to irregularly circular, bundle scars numerous, in circle.

blade ovate, often deeply and irregularly lobed, (6-)8-10 × 3-6 cm, base cuneate, truncate, or cordate, margins coarsely serrate to crenate, apex acute to short-acuminate;

surfaces abaxially glabrous or sparingly pubescent along major veins or in tufts in axils of principal lateral veins and midribs, adaxially glabrous to sparsely pubescent.

blade broadly ovate, sometimes irregularly lobed, 10-18(-36) × 8-12(-15.5) cm, base rounded to nearly cordate, sometimes oblique, margins serrate or crenate, apex abruptly acuminate;

surfaces abaxially sparsely to densely pubescent or puberulent, adaxially with short, antrorsely appressed trichomes, usually scabrous.

staminate and pistillate on same or different plants.

staminate and pistillate on different plants.

sepals distinct, green with red tip, ca. 1.5 mm, pubescent;

filaments ca. 2.7 mm.

sepals connate at base, green tinged with red, 2-2.5 mm, pubescent outside, ciliate toward tip;

stamens 4;

filaments 3-3.5 mm.

ovary green, ovoid, slightly compressed, ca. 2 mm, glabrous;

style branches divergent, red-brown, 0.5-1 mm;

stigma papillose.

calyx tightly surrounding ovary;

ovary green, broadly ellipsoid or obovoid, slightly compressed, 1.5-2 × 1 mm, glabrous;

style branches divergent, whitish, sessile, ca. 1.5 mm;

stigma papillose.

peduncle and axis pubescent; staminate catkins 2.5-4 cm; pistillate catkins 5-8 mm.

peduncle pubescent; staminate catkins 3-5 cm; pistillate catkins 8-12 × 5-7 mm.

red when immature, becoming black, purple, or nearly white, cylindric, 1.5-2.5 × 1 cm;

achenes light brown, ovoid, 2-3 mm.

black or deep purple, cylindric, (1.5-)2.5-4(-6) × 1 cm; fleshy calyx surrounding achenes;

achenes yellowish, oval, flattened, ca. 2 mm, smooth.