11. Achnatherum jacquemontii (Jaubert & Spach) P. C. Kuo & S. L. Lu, Fl. Reipubl. Popularis Sin. 9(3): 323. 1987.
干生芨芨草 gan sheng ji ji cao
Stipa jacquemontii Jaubert & Spach, Ill. Pl. Orient. 4: 60. 1851; Lasiagrostis jacquemontii (Jaubert & Spach) Munro ex Boissier; Stipa sibirica Linnaeus var. pallida J. D. Hooker.
Perennial, densely tufted from tough rootstock. Culms wiry, 30–70 cm tall, 1–1.5 mm in diam., 2–4-noded. Leaf sheaths glabrous, lower longer than internodes; leaf blades setaceous, convolute, 10–25 cm, ca. 0.8 mm wide, abaxial surface smooth, adaxial surface pubescent; ligule truncate, ca. 0.3 mm. Panicle contracted, narrow, 10–20 cm; branches 2 to several per node, laxly suberect, delicate, 2–7 cm, with spikelets to base. Spikelets 5–7 mm, greenish or purplish; glumes subequal, elliptic-lanceolate, 3-veined, membranous, smooth, apex acute; callus obtuse, 0.3–0.4 mm; lemma 4–5 mm, membranous, pilose throughout, apex 2-toothed, teeth 0.3–0.4 mm; awn persistent, 2–3 cm, very fine, weakly 2-geniculate, column twisted, scabrid throughout; palea 2/3 length of lemma. Anthers 2.8–3.5 mm, bearded at apex. Fl. and fr. Jul–Sep.
Dry mountain slopes, especially in rock crevices; ca. 3300 m. Xizang [E Afghanistan, NW India, Kashmir, N Pakistan].
This is a well-defined species from rocky places in the W Himalayas. Achnatherum duthiei has a similar but wider distribution. Besides the key characters, A. jacquemontii can also be distinguished from A. duthiei by its short ligule, whorls of panicle branches bearing more spikelets, and shorter palea.