Tufted or rhizomatous perennials. Leaf-blades flat or convolute. Inflorescence a spike. Spikelets 2-11-flowered, sessile or very shortly pedicelled, imbricate, solitary or in groups of 2-3 at the nodes of the tough rhachis; rhachilla disarticulating above the glumes and between the florets, or sometimes the spikelets falling entire; glumes 1-11-nerved, awned or awnless, rounded on the back or sometimes keeled towards the tip; lemmas 5-nerved, awned or awnless; palea 2-keeled.