Perennials, rarely annuals. Leaf-blades linear or lanceolate-linear, flat; ligule reduced to a fringe of hairs. Inflorescence a linear to oblong or ovate panicle, the spikelets paired or rarely in threes. Spikelets 2-flowered, disarticulating above the glumes and between the florets, the lower floret male; glumes membranous-scarious to chartaceous or rarely thinly coriaceous, 3-5-nerved, the lower narrowly ovate to elliptic-ovate or elliptic-oblong, acute or obtuse, the upper as long as the spikelet, lanceolate to ovate or elliptic-oblong, caudate-acuminate; lower lemma (3)5-9 (-11)-nerved; upper lemma membranous to coriaceous, 7-9-nerved, deeply bifid, with the lobes acute and sometimes produced into a fine scaberulous bristle, transversely bearded on the back with a continuous beard below each lobe or with 6-8 distinct tufts of hair, awned from the sinus with a geniculate awn twisted below the knee; callus obtuse; palea winged, the wings usually bearing a lateral appendage at the apex; anthers 3. Caryopsis oblong to obovate-oblong, glabrous.