Oak

Trees or shrubs, evergreen or winter-deciduous, sometimes rhizomatous. Terminal buds spheric to ovoid, terete or angled, all scales imbricate. Leaves: stipules deciduous and inconspicuous (except in Quercus sadleriana). Leaf blade lobed or unlobed, thin or leathery, margins entire, toothed, or awned-toothed, secondary veins either unbranched, ± parallel, extending to margin, or branching and anastomosing before reaching margin. Inflorescences unisexual, in axils of leaves or bud scales, usually clustered at base of new growth; staminate inflorescences lax, spicate; pistillate inflorescences usually stiff, with terminal cupule and sometimes 1-several sessile, lateral cupules. Staminate flowers: sepals connate; stamens (2-)6(-12), surrounding tuft of silky hairs (apparently a reduced pistillode). Pistillate flower 1 per cupule; sepals connate; carpels and styles 3(-6). Fruits: maturation annual or biennial; cup variously shaped (saucer- to cup- or bowl- to goblet-shaped), without indication of valves, covering base of nut (rarely whole nut), scaly, scales imbricate or reduced to tubercles, not or weakly reflexed, never hooked; nut 1 per cup, round in cross section, not winged. x = 12.