Perennials, usually with wide spreading scaly rhizomes. Culms erect, robust. Leaf blades long, tough; ligule a line of hairs. Inflorescence of racemes, these subdigitate or disposed along an axis, few to many; spikelets appressed or pectinate; rachis triquetrous, terminating in a naked point. Spikelets strongly laterally compressed, lanceolate or narrowly oblong, floret 1, without rachilla extension, disarticulating below glumes and falling entire; glumes unequal, keeled; lower glume shorter than floret; upper glume longer than floret, papery, 1–3-veined, sometimes additional veins present, apex narrowly acute to shortly awned; lemma keeled, firm with wide membranous margins, lateral veins obscure, apex subacute; palea equaling or exceeding lemma. Lodicules often absent. Caryopsis fusiform, embryo nearly as long as caryopsis. x = 10.

This genus is adapted to the saline environment of the coast. Species with spreading rhizomes form colonies in tidal saltmarshes and are particularly suitable for stabilizing coastal mud flats.

Seventeen species: both coasts of the Americas, Atlantic coasts of Europe and Africa, especially in temperate and subtropical regions; two species (both introduced) in China.

(Authors: Sun Bixing (孙必兴 Sun Bi-sin); Sylvia M. Phillips)