Robust perennial (culms geniculate, rooting at nodes below), up to 1.5 m high. Leaf blades 50-250 mm long, 3-15 mm wide. Spikelets 2.5-3.5 mm long; lower glume produced above beadlike swelling as a short, truncate in-turned cuff; upper glume acute, not mucronate or awned.