5. Deyeuxia abnormis J. D. Hooker, Fl. Brit. India. 7: 268. 1896 [“1897”].
不育野青茅 bu yu ye qing mao
Agrostis nagensis Bor; Calamagrostis abnormis (J. D. Hooker) U. Shukla; Deyeuxia nagensis (Bor) Veldkamp.
Perennial, loosely tufted. Culms laxly ascending from a decumbent base, often scrambling, 30–90 cm tall, 4–10-noded, sometimes branched. Leaf sheaths scabrid; leaf blades linear, flat, 9–12 cm, 2–5 mm wide, apex acute; ligule 1–2 mm, truncate. Panicle effuse, 8–30 cm; branches loosely spreading, secondary and tertiary branches well developed. Spikelets 2.5–3.5 mm, green or purplish; glumes lanceolate, equaling or slightly exceeding floret, lower glume 2.6–3.4 mm, upper glume 2.5–3.1 mm, keel scabrid above middle, apex acuminate; callus hairs 1/3–1/2 length of lemma; lemma slightly shorter than or subequaling glumes, apex narrowly obtuse, awnless; palea 2/3 as long as lemma; rachilla penicillate, including hairs 1.8–2.6 mm. Anthers ca. 0.5 mm. Fl. and fr. Nov.
Grassy and stony places in uplands; ca. 1900 m. Yunnan [Bhutan, NE India].
This grass lies on the boundary between Agrostis and Deyeuxia. It has an open panicle of small spikelets as in Agrostis, but a bearded callus and rachilla extension as in Deyeuxia. It is sometimes known as A. zenkeri Trinius (Calamagrostis zenkeri (Trinius) Davidse; D. zenkeri (Trinius) Veldkamp), a name which probably applies only to a grass from S India. Deyeuxia abnormis is very similar to D. petelotii, with which it is often confused, but is more robust with a laxer, spreading habit and a larger, more branched panicle. Other differences are given in the key.