Flora of North America species comparison

of mature trunks and branches creamy to silvery white, smooth, exfoliating as long strands;

lenticels dark, horizontally expanded.

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.

pendulous;

twigs glabrous, usually dotted with small resinous glands.

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

blade broadly ovate to rhombic with 5–18 pairs of lateral veins, 3–7 × 2.5–5 cm, base cuneate, rarely truncate, margins coarsely and sharply doubly serrate, apex acuminate;

surfaces abaxially glabrous to sparsely pubescent, covered with 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 to nearly pendulous, cylindric, 2–3.5 × 0.6–1 cm, shattering with fruits in fall;

scales adaxially sparsely pubescent, lobes diverging at middle, central lobe obtuse, much shorter than lateral lobes, lateral lobes broad, rounded, extended.

with wings much broader than body, broadest near center, 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, 56.