Monoecious annuals or perennials. Leaf-blades flat, linear; ligule membranous. Inflorescence composed of terminal and axillary racemes, these solitary or gathered into leafy false panicles. Racemes male or with one to several female spikelets at the base, subtended by spathes, these resembling the leaves or with reduced blades; rhachis fragile above and below each female spikelet. Male spikelets 2-flowered, solitary or paired and then with one spikelet sessile, the other pedicelled; lower glume herbaceous, shallowly concave, narrowly winged on each side; upper glume chartaceous, rarely herbaceous, narrower; lemmas similar, membranous, paleate, both staminate or the upper empty; stamens 3. Female spikelets 2-flowered, oblong, dorsally compressed; lower glume thickly coriaceous, embracing but not concealing the rhachis between its inflexed margins, enclosing the upper glume and florets; upper glume membranous or chartaceous; lemmas hyaline, the lower empty, paleate or not, the upper fertile, paleate. Caryopsis orbicular, compressed, channelled on the ventral side.