羽穗草 yu sui cao

Briza bipinnata Linnaeus, Syst. Nat., ed. 10, 2: 875. 1759; Eragrostis cynosuroides (Retzius) P. Beauvois; Poa cynosur-oides Retzius.

Coarse perennial forming large leafy tussocks, also with widely spreading scaly rhizomes. Culms rigid, branched at base and covered with leathery yellowish sheaths, 80–100 cm tall, ca. 7 mm in diam. Leaf sheaths glabrous; leaf blades flat or inrolled, tough, 18–30 × 0.4–1 cm, adaxial surface and margins scabrid, abaxial surface rather smooth, apex long acuminate; ligule ca. 0.3 mm. Inflorescence 20–60 × 2–3 cm; racemes ascending or spreading, crowded or spaced, 0.5–3.5 cm; main axis and rachis hispidulous. Spikelets elliptic or elliptic-oblong, 2–10 mm, stramineous or purplish, florets 3–10; glumes ovate-lanceolate; lower glume 0.7–1.5 mm; upper glume 1.1–2 mm; lemmas ovate-lanceolate, 1.8–2.7 mm; palea keels scabrid. Fl. and fr. summer.

Arid regions with water table near surface. Hainan [Cambodia, India, Myanmar, Pakistan, Thailand, Vietnam; N and NE Africa, SW Asia, Australia (Cocos Islands)].

This is a tough grass of arid regions, useful as a soil binder.