Flora of North America species comparison

dark brown, smooth, becoming darker and breaking into shallow fissures in age;

lenticels pale, horizontal.

light to dark gray, reddish, or brown, smooth, or in age broken into irregular plates;

lenticels present or absent, conspicuous, enlarged or unexpanded.

blade obovate to nearly orbiculate, 3–9 × 3–8 cm, leathery, base obtuse to broadly cuneate, margins flat, coarsely and often irregularly doubly serrate to nearly dentate, major teeth acute to obtuse or rounded, apex often retuse or obcordate, or occasionally rounded;

surfaces abaxially glabrous to sparsely pubescent, often more heavily on veins, both surfaces heavily resin-coated.

blade narrowly ovate to elliptic, base cuneate to narrowly rounded, margins doubly serrate, with distinctly larger secondary teeth, apex acute or short-acuminate to obtuse.

formed season before flowering and exposed during winter; staminate catkins in 1 or more clusters of 2–5, 4–13 cm; pistillate catkins in 1 or more clusters of 2–5.

formed season before flowering and exposed during winter.

ovoid to nearly globose, 1.2–2.5 × 1–1.5 cm;

peduncles 1–10(–20) mm.

ovoid to nearly cylindric;

peduncles relatively short and stout.

buds stipitate, ellipsoid to obovoid, 6–10 mm, apex obtuse;

stalks 2–5 mm;

scales 2–3, outer 2 equal, valvate, usually heavily resin-coated.

buds stipitate, ellipsoid, 4–7 mm, apex rounded to nearly acute;

stalk 1–3 mm;

scales 2–3, equal, valvate, resin-coated.

before new growth in spring.

before new growth in spring.

obovate, wings reduced to narrow, thickened ridges.

elliptic to obovate, wings narrower than body, irregular in shape.

= 28.