Annual or short lived-perennials; tufted or mat-forming. Roots minute, arising at culm base or at internodes; tubers usually absent. Rhizome ascending or horizontal, either below or above ground (runners). Culm 0.8 – 80 (200) cm tall, consisting of several internodes or reduced to peduncle only. Leaf comprising of a closed sheath and blade; blade a minute lobe or elongated to form a linear blade. Inflorescence comprising 1 – several spikelets, subtended by a single involucral bract. Bract shorter than spikelets resulting in a terminal inflorescence, or longer and continuing in direction of culm resulting in a pseudolateral inflorescence. Spikelets terete, with spirally arranged glumes, sometimes proliferating. Glumes ovate to obovate, green to reddish-brown, carinate, acute to obtuse, arranged on the rachilla with the space between successive glumes <0.1 mm. Flowers bisexual; perianth segments absent. Stamens 1 – 3; filament ribbon-like; anther 0.2 – 2.5 mm long, apex crested. Pistil with 2 – 3 stigma branches. Nutlets 2- or 3-sided, smooth, reticulate, papillose or striate; gynophore absent.