Dioecious, tufted perennial, 0.2-0.6 m tall, often forming widely spreading clumps. Fertile culms blue-green, unbranched, longitudinally grooved, sheaths tightly rolled around culm, green, brown, red-brown or grey. Male spikelets 2 or more, ± globose. Female spikelet solitary, rarely paired, elliptical. Nut torpedo-shaped with truncate bases.
Dioecious, clumped, rhizomatous perennial, 20-60 cm, culms simple, round, striate, bluish. Female spikelet solitary, rarely paired, bracts acuminate.