Flora of North America species comparison

erect or prostrate, equal;

twigs glabrous or hairy, hairs appressed to spreading, short to elongate, combretaceous.

persistent, alternate and spiral;

stipules absent;

petiole not differentiated proximally and no part of it persistent, nectar glands glands conspicuous to inconspicuous, at junction of petiole and blade base;

blade leathery, venation brochidodromous, apex often acuminate to acute, occasionally obtuse, rarely rounded-mucronate;

pit-domatia conspicuous, at junction of abaxial veins with midvein.

terminal and axillary, racemes or panicles of spherical or oblong heads, sometimes lateral ones reduced to single head;

bracteoles absent.

inconspicuous, each in axil of a bract, unisexual (staminate and pistillate on different plants);

hypanthium shallowly cupulate, 0.3–0.5 mm, from constriction at apex of ovary, pubescent abaxially, often densely so;

sepals 5, green to pale green, sometimes red-tinged, triangular, glabrate to pubescent abaxially;

petals 0;

stamens 5–10, long-exserted, with well-developed staminodia;

nectary disc atop ovary, pubescent;

ovary clearly flattened;

style straight to slightly curved, free from hypanthium, with well-developed pistillode;

ovules 2.

somewhat flattened, ellipsoid to shortly obovoid, ridged or winged;

ridges 2, forming shortly developed wings, slightly convex abaxially, concave adaxially;

hypanthium and calyx persistent;

fruits densely clustered in conelike heads, fragmenting in age.