江萨早熟禾 jiang sa zao shu he

Poa jaunsarensis Bor.

Plants grayish to tawny grayish, perennials, rhizomatous. Culms 40–80 cm tall, 1.5–2 mm in diam., nodes 3 or 4. Lower leaf sheaths retrorsely scabrid, 14–19 cm, 1.1–1.6 × as long as blade, uppermost closed for (1/5–)1/4 of length; blades flat or folded, moderately thin, 8.5–19 cm × 2.5–4 mm, uppermost 8.5–13 cm, surfaces and margins scabrid, apex slender prow-tipped; ligule 2.5–5 mm, apex entire to lacerate, abaxially scabrid. Panicle loosely contracted or somewhat open, oblong to pyramidal, 10–19 × 2–5 cm; branches loosely ascending, 3–5 per node, proximally rounded, sparsely scabrid, distally densely scabrid on and between angles, longest 4–8 cm with spikelets moderately crowded in distal 1/2. Spikelets elliptic, 4–5 mm, florets 2–4; vivipary absent; rachilla glabrous; glumes thinly papery, scabrid on keels and marginal veins, lower glume lanceolate to oblong, 2.3–3.5 mm, 1- or 3-veined, apex acuminate, upper glume elliptic to oblong, 3.5–3.8 mm; lemmas 3.5–4 mm, keel villous for 1/2 of length, marginal veins to 1/3; callus webbed; palea keels scabrid, glabrous. Anthers 1.4–2 mm. Fl. and fr. Jun–Aug.

High-elevation grassy places on slopes; 3300–4500 m. Sichuan, Xizang [India, Kashmir, Nepal].

Poa lhasaensis needs further study. The types of P. jaunsarensis and P. lhasaensis are large plants with long upper culm leaves (10–13 cm), upper sheaths closed for only 1/4 their length, and the lowest sheaths moderately to densely retrorsely scabrid; P. jaunsarensis has the uppermost ligule to 5 mm long and lacerate. The few specimens referable to P. jaunsarensis could be accommodated in P. pratensis except for the several long, relatively scabrid leaf blades along the culms, their unusually open sheaths, long ligules, and the thin glumes, which in combination suggest the specimens might be something else, perhaps intermediates between P. pratensis and P. asperifolia. The anthers are longer and the panicle branches more numerous in the type specimens than in the original descriptions of both P. lhasaensis and P. jaunsaren-sis.