27. Deyeuxia tianschanica (Ruprecht) Bor, Kew Bull. [4]. 1949: 66. 1949.
天山野青茅 tian shan ye qing mao
Calamagrostis tianschanica Ruprecht, Sert. Tianschan. 34. 1869.
Perennial, loosely tufted, rhizomatous; rhizomes slender, spreading. Culms erect, 15–50 cm tall, 1–2 mm in diam., scabrid below panicle, 2–3-noded. Leaf sheaths smooth or scabrid, slightly inflated; leaf blades flat with involute margins, 4–10 cm, 2–3 mm wide, adaxial surface scabrid with numerous short spinules, apex acute; ligule 3–4 mm, lacerate. Panicle contracted, spikelike, dense or branches distinct, 3–8 × 1–1.5 cm; branches 1–2 cm, scabrid. Spikelets 4–6 mm, purple; callus hairs 1/3–1/2 length of lemma; glumes narrowly lanceolate, subequal, lower glume 1-veined, upper glume 3-veined, scabrid, apex acuminate; lemma 3–4.5 mm, apex 4-denticulate; awn arising from lower 1/4 of lemma, 5–6 mm, geniculate with twisted column; palea slightly shorter than lemma; rachilla ca. 2 mm, including hairs up to 3.5 mm. Anthers 1.5–2 mm. Fl. Jul–Sep.
Stony mountain slopes and alpine meadows, especially along riversides; 1000–5200 m. Gansu, Qinghai, Xinjiang [Kyrgyzstan, Tajikistan (Pamirs)].
This species is close to the variable Deyeuxia holciformis, but the different upper leaf surface provides a definite distinguishing character.