Rhizome neck 5–8 cm. Culms 7–9 m, 3–6 cm in diam.; internodes terete, 20–28 cm, initially white powdery, glabrous; wall 3–7 mm thick; supra-nodal ridge level; sheath scar weakly prominent, glabrous. Branches 7–10 per node; buds elliptic or oblong, margins densely light yellow ciliate. Culm sheaths persistent, narrowly triangular, much longer than internodes, leathery, sparsely brown setose, longitudinal ribs prominent, margins densely brown ciliate, apex triangular; auricles absent; oral setae few, erect, yellow-brown, 5–8 mm; ligule purple, truncate or convex, ca. 1 mm, glabrous; blade erect, linear-lanceolate, usually slightly rugose. Leaves 2 or 3 per ultimate branch; sheath glabrous; auricles absent; oral cilia few, erect, light yellow, 1–2 mm; ligule truncate, ca. 1 mm, margins glabrous; external ligule densely pubescent with long, erect, gray hairs; blade narrowly lanceolate, 5–10.5 × 0.3–0.6 cm, glabrous, secondary veins 2- or 3-paired, transverse veins distinct, base cuneate, one margin spinescent-serrulate, other margin obscurely so. Inflorescence unknown. New shoots Aug.

The culms are considered the best for making arrows.

* 2400–2900 m. NW Yunnan.