Tufted, rarely stoloniferous annual. Culms erect, geniculate at base to c. 120 cm high. Leaves glabrous; blade flat or weakly folded, 3–30 cm long, 4–10 mm wide, usually rather flaccid; ligule 0.4–2 mm long. Panicle cylindric, 1–10(–20) cm long, c. 0.5 cm wide. Spikelets elliptic, shortly pointed, 1.5–3.5 mm long, each subtended by an involucre of 6–8 antrorsely barbed bristles 3–12 mm long; lower glume 3-nerved, ovate, c. half as long as spikelet; upper glume 5-nerved, ovate, acute, half to about three-quarters as long as spikelet; lower floret neuter or male, its lemma equal to spikelet, its palea almost as long; fertile lemma equal to spikelet, minutely pointed, transversely ridged. Flowers Feb.–May.