Annual or perennial herbs. Perennials with a woody rhizome. Culms with leaves and nodes throughout. Leaves usually flat. Ligule present, tubular. Inflorescence paniculate, consisting of 1-several clusters of spikelets or compound corymbs of spikelets, the inflorescence branches usually hairy. Spikelets of numerous overlapping glumes, the 2 lowest sterile, the upper with bisexual flowers. Glumes spirally arranged, sometimes 5-ranked,  pubescent with the midrib excurrent into a mucro. Perianth segments 3 or 6, sometimes 0, sometimes in 2 whorls of differing type. Stamens 2-3. Stigmas 3. Nutlet sessile, triangular, obovoid.