Culms to 5 m, 1–2.5 cm in diam.; internodes green, longitudinally striate, terete, flattened above branches, 10–30 cm, initially white powdery, glabrous; supra-nodal ridge very prominent and glabrous; sheath scar prominent, retrorsely yellow-brown setose, with remains of sheath base; intranode 3–5 mm, sometimes black scurfy. Branches 3–5 per node, 30–45 cm, irregularly triangular at base. Culm sheath soon deciduous, pale yellow, obviously striate, oblong-triangular, 21–22 × 5–10 cm, abaxially sparsely yellow-brown setose, more densely hairy at base, margins initially densely brown hispid; auricles absent; oral setae 5–10 mm, gray-yellow hairy; ligules arched, ca. 1 mm, glabrous; blades reflexed, linear-lanceolate, 3–10 ×0.2–0.4 cm, glabrous, obviously longitudinally veined, margins involute. Leaves 3–5 per ultimate branch; sheath 5.5–7 cm; auricles absent; ligules purple, arched or truncate, 1–2 mm; blades abaxially gray, lanceolate to narrowly lanceolate, 9–19 × 1.2–2.5 cm, papyraceous, glabrous, secondary veins 5–7-paired, transverse veins distinct, margins sparsely serrulate. Inflorescence unknown.