Plants usually perennial; usually tightly to loosely cespitose, sometimes rhizomatous. Culms annual or perennial, not woody, branches 1 to many at the upper nodes. Leaves basally concentrated to evenly distributed; sheaths open, margins not fused, sometimes ciliate distally, basal sheaths sometimes concealing axillary panicles (cleistogenes), sometimes wider than the blade; collars sometimes with tufts of hair at the sides extending to the top of the sheaths; auricles absent; ligules scarious, often ciliate, cilia usually shorter than the base, ligules of the lower and upper cauline leaves sometimes differing in size and vestiture; pseudopetioles absent; blades linear to narrowly lanceolate, venation parallel, cross venation not evident, cross sections non-Kranz, without arm or fusoid cells; epidermes of adaxial surfaces sometimes with unicellular microhairs, cells not papillate. Inflorescences usually terminal panicles, occasionally reduced to racemes in depauperate plants, sometimes 2-3 panicles developing from the highest cauline node. Spikelets usually with 1 floret, sometimes with 2-6 florets, laterally compressed to terete; rachillas not prolonged beyond the base of the floret in spikelets with 1 floret, prolonged beyond the base of the distal floret in spikelets with 2-6 florets, prolongation hairy, hairs 2-3 mm; disarticulation above the glumes and beneath the florets. Glumes usually exceeding the floret(s), always longer than 1/4 the length of the adjacent floret, 1-10-veined, narrowly lanceolate to ovate, hyaline or membranous, flexible; florets usually terete, sometimes laterally or dorsally compressed; calluses usually well-developed, rounded or blunt to sharply pointed, often antrorsely strigose; lemmas lanceolate, rectangular, or ovate, membranous to coriaceous or indurate, 3-5-veined, veins inconspicuous, apices entire, bilobed, or bifid, awned, lemma-awn junction usually conspicuous, awns 0.3-30 cm, not branched, usually terminal and centric or eccentric, sometimes subterminal, caducous to persistent, not or once- to twice-geniculate, if geniculate, proximal segment(s) twisted, distal segment straight, flexuous, or curled, not or scarcely twisted; lodicules 2 or 3; anthers 1 or 3, sometimes differing in length within a floret; ovaries glabrous throughout or pubescent distally; styles 2(3-4)-branched. Caryopses ovoid to fusiform, not beaked, pericarp thin; hila linear; embryos less than 1/3 the length of the caryopses. x = 7, 8, 10, 11, 12.