Flora of North America species comparison

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

lenticels dark, horizontally expanded.

gray to dark brown, smooth, close;

lenticels inconspicuous, unexpanded.

pendulous;

twigs glabrous, usually dotted with small resinous glands.

without taste and odor of wintergreen, glabrous to sparsely or moderately pubescent, with or without heavy resinous coating, sometimes covered with warty resinous glands.

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 broadly orbiculate or obovate-orbiculate to reniform, with 2–6 pairs of lateral veins, often broader than long, base rounded to nearly cordate, margins deeply crenate, apex rounded;

surfaces abaxially glabrous to sparsely or moderately pubescent.

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.

erect, nearly cylindric, shattering with fruits in fall.

with wings much broader than body, broadest near center, extended beyond body apically.

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

and pistillate catkins produced season before flowering but retained in buds during winter, expanding along with new growth in spring.

= 28, 56.