日本短颖草 ri ben duan ying cao

Brachyelytrum erectum var. japonicum Hackel, Bull. Herb. Boissier 7: 647. 1899; Brachyelytrum erectum subsp. japonicum (Hackel) T. Koyama & Kawano.

Perennial from a short knotty rhizome. Culms solitary or loosely tufted, slender, erect, 40–100 cm tall, unbranched, 6–7-noded. Leaf sheaths shorter than internodes, glabrous or puberulent; leaf blades linear-lanceolate, thin, soft, 8–15 × 0.6–0.8 cm, scabridulous or puberulous when young, margins ciliate, apex acuminate; ligule 2–5 mm, obtuse to acuminate, usually erose. Panicle narrow, 9–15 cm; branches short, suberect, capillary, scabrous, bearing a few subsessile spikelets. Spikelets 8–10 mm, gray-green; lower glume 0.4–1.5 mm; upper glume 1–4 mm, 1-veined or obscurely 3-veined at base, margins scarious; lemma narrowly lanceolate, 8–10 mm, rigid, 5-veined, scabrous on veins; awn 1.2–1.8 cm, slender, scabrous; palea 2-toothed at apex; callus ca. 0.8 mm, shortly pilose. Anthers 3.3–4.5 mm. Rachilla extension 4–7 mm. Fl. Jun–Jul.

Woodland shade. Anhui, Jiangsu, Jiangxi, Yunnan, Zhejiang [Japan, Korea (Cheju Island)].

This species is very similar to the other two species of the genus in North America, but these have wider leaf blades (0.8–2 cm wide) and a shorter lower glume (0.2–0.7 mm).