Usually tufted annuals or perennials, of medium height. Leaf-sheath open, or closed near base, often keeled. Ligule a ciliate rim. Leaf-blade flat to folded, rolled in bud. Culm erect, or ascending from geniculate base. Inflorescence usually an erect, dense, cylindric, spike-like panicle, or more branched and open, each spikelet subtended by one to several persistent scabrid bristles (Ø branchlets) almost to entirely suppressed in plants with plicate leaves (). Spikelets 2-flowered, usually falling entire at maturity; lower floret ♂ or Ø, upper floret ☿. Glumes membranous, unequal, glabrous, lower generally the shorter, upper ≤ spikelet. Lower floret: lemma of same texture as glumes, = spikelet, dorsally flattened to slightly depressed; palea sometimes 0. Upper floret: lemma ≤ spikelet, crustaceous, often rugose, naviculate; palea ≈ lemma and similar in texture; lodicules 2, broadly cuneate, rather fleshy; stamens 3; styles free; caryopsis tightly enclosed by hardened anthoecium, embryo c. ½ length of caryopsis, hilum basal, punctiform or orbicular.