Description from Flora of China
Panicum alopecuroides Linnaeus, Sp. Pl. 1: 55. 1753; Cenchrus purpurascens Thunberg; Gymnotrix japonica (Trinius) Kunth var. viridescens Miquel; Pennisetum alopecuroides var. erythrochaetum Ohwi; P. chinense Steudel; P. compressum R. Brown; P. dispiculatum L. C. Chia; P. japonicum Trinius; P. purpurascens (Thunberg) Kuntze (1891), not Kunth (1816).
Perennial forming dense tussocks. Culms stout, 30–120 cm tall, hispid below inflorescence. Leaf sheaths papery, keeled, imbricate at culm base; leaf blades linear, flat or often involute, 10–80 × 0.3–1 cm, base papillose-hispid, apex long acuminate; ligule 0.5–2.5 mm. Inflorescence linear, 5–25 × 1.5–3.5 cm; axis hispid, peduncle stumps short with crateriform tips; involucre usually enclosing one spikelet, rarely 2, basal stipe (1–)2–3 mm; bristles greenish or purple, longest 2–3 cm but not conspicuously longer than the others, all slender, hispid. Spikelet lanceolate, 5–8 mm; lower glume 0.6–3 mm, 0–1-veined, obtuse; upper glume ovate-lanceolate, 1/3–2/3 as long as spikelet, 3–5-veined; lower lemma as long as spikelet, 7–11-veined; upper lemma lanceolate, as long as spikelet, papery, acuminate; anthers usually glabrous, occasionally with 1 or 2 hairs at tip. Fl. and fr. summer and autumn. 2n = 18.
This species is used for forage.
Grassy hillsides, roadsides, field margins; sea level to 3200 m. Anhui, Beijing, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Heilongjiang, Henan, Hubei, Jiangsu, Jiangxi, Shaanxi, Shandong, Sichuan, Taiwan, Tianjin, Xizang, Yunnan, Zhejiang [NE India, Indonesia, Japan, Korea, Malaysia, Myanmar, Philippines; Australia, Pacific Islands (Polynesia)].