Flora of North America species comparison

of mature trunks and branches light grayish brown to dark brown or nearly black, smooth, close, furrowed and broken into shallow scales with age.

when young dark reddish brown, in maturity light reddish brown to tan or brownish or grayish white, smooth, rather close or readily exfoliating in paper-thin sheets;

lenticels pale, horizontal, in maturity dark, horizontally expanded.

with taste and odor of wintergreen when crushed, glabrous to sparsely pubescent, usually covered with small resinous glands.

without taste and odor of wintergreen, usually covered with short bristly hairs.

blade ovate to oblong-ovate with 12–18 pairs of lateral veins, 5–10 × 3–6 cm, base rounded to cordate, margins finely and sharply serrate or obscurely doubly serrate, teeth fine, sharp, apex acuminate;

surfaces abaxially mostly glabrous, except sparsely pubescent along major veins and in vein axils, often with scattered, minute, resinous glands.

blade ovate or rhombic-ovate, margins serrate, apex acute;

surfaces abaxially sparsely pubescent to velutinous, especially along major veins and in vein axils, without prominent resinous glands.

erect, ovoid to nearly globose, 1.5–4 × 1.5–2.5 cm, usually remaining intact for a period after release of fruits in fall;

scales mostly glabrous, lobes diverging at or proximal to middle, central lobe short, cuneate, lateral lobes extended to slightly ascending, longer and broader than central lobe.

with wings narrower than body, broadest near center, not extended beyond body apically.

with wings equal to or somewhat broader than body, broadest near summit, extended beyond body apically.

catkins pendulous or subpendulous, cylindric, shattering with fruits in late fall;

scales puberulent to glabrous, often ciliate, lobes diverging at middle.

= 28.