Perennial, densely tufted on a short oblique rhizome, up to 2 ft. high; innovations intravaginal. Culms erect, very slender, smooth and glabrous, 2–3-noded, with the uppermost node at the middle or well below it, the lower internodes mostly shorter than the sheaths. Basal leaf-sheaths loose, wide, more or less spongy, up to 3 in. long, brownish or grey or suffused with livid purple, upper tight, green, sulcate-striate when dry, all with rounded minutely puberulous shoulders at the mouth, otherwise glabrous and smooth; ligules short, truncate, ciliolate; blades erect, filiform, subterete or laterally slightly compressed, 5-angular and 5-sulcate with the frontal groove deepest, up to 6 in. by hardly 1/2 lin. in diam., spongy, quite glabrous, none of the vascular bundles with sclerenchymatic girders. False spikes erect on at length long-exserted peduncles, cylindric, 1 1/2–5 in. by 1 1/2–2 lin., more or less dense, continuous or here and there slightly interrupted; common axis very slender; pedicels very short or up to 3/4 lin. long, puberulous. Spikelets ovate in outline, acute or acuminate, symmetrical or slightly oblique when gaping, up to 1 lin. long, pale greyish-green to straw-coloured; loosely puberulous with the hairs tubercle-based. Glumes thinly membranous, ovate; lower subobtuse, over half to two-thirds the length of the glume, 5-nerved; upper acute, 7-nerved with the nerves fine, but ultimately prominent. Lower floret ♂: valve very similar to the upper glume, but less puberulous; valvule three-quarters the length of the valve, narrow. Upper floret hermaphrodite, ovate, subobtuse, 1/2– 2/3 lin. long, whitish, polished; anthers 1/2 lin. long.
