18. Poa polycolea Stapf in J. D. Hooker, Fl. Brit. India. 7: 342. 1896 [“1897”].
多鞘早熟禾 duo qiao zao shu he
Poa chalarantha Keng ex L. Liu; P. gilgitica Dickoré; P. lithophila Keng ex L. Liu; P. maerkangica L. Liu; P. triglumis Keng ex L. Liu.
Perennials, loosely to densely tufted, often shortly stoloniferous or rhizomatous; shoots extra- and intravaginal. Culms erect, decumbent, or ascending, usually several per tuft, 10–60(–75) cm tall, 0.5–1 mm in diam., smooth, nodes 1–3, 1 or 2 exserted, uppermost usually 1/4–1/3 way up. Lowermost leaf sheaths closely overlapping, straw colored, often somewhat thickly papery and persistent, not or only slightly fibrous, lower and middle sheaths 1–1.3(–1.5) mm wide distally, with distinct closely spaced ribs, membranous between ribs, smooth or scabrid, sometimes retrorsely hispidulous, uppermost smooth, glabrous, 4–20 cm, 1/2–4 × as long as blade, closed for ca. 1/2 of length; blade flat or folded with inrolled margins, thin, 2–10(–20) cm × 0.8–1.5(–2.5) mm, abaxially often shiny, smooth, ribs distinct, margins finely scabrid, adaxially smooth or sparsely scabrid, glabrous or strigose, of tillers with margins inrolled, to 20(–30) cm, adaxially smooth or scabrid, glabrous or pilulose to strigose, visible veins 5–9 including keel; lower ligules 0.1–0.5 mm, adaxially smooth or scabrid, apex truncate, glabrous or ciliolate, upper to 0.5–1(–2.2) mm, apex truncate to obtuse, collar margins abruptly flared, smooth or scabrid, glabrous or lower ones ciliate to strigose. Panicle open, erect or diffuse, 5–15(–20) × 2–9 cm, longest internodes 1–3(–3.5) cm; branches spreading to reflexed, 2–5 per node, capillary, usually angled, scabrid, longest 3–9 cm with 2–9 spikelets in distal 1/3–1/2. Spikelets lanceolate, green or purple tinged, 4–7 mm, florets 2–4(–5), commonly female, sometimes whole inflorescence female; vivipary absent; rachilla internodes 0.7–1.6 mm, smooth or slightly bumpy, or scabrid, usually visible laterally; glumes membranous-papery, generally shiny, keel and veins scabrid, surface smooth (rarely slightly scabrid distally), apex acute to acuminate, lower glume subulate, 1.5–3(–4) mm, 1/3–1/2 as wide as upper, 1(or 3)-veined, upper glume elliptic, 3–4(–5) mm, 3-veined; lemmas lanceolate, very thinly papery, 3–5(–5.5) mm, keel straight, 5(or 7)-veined, margins membranous, apex acute to acuminate, glabrous, or keel sparsely pilulose to shortly villous for 2/3 of length, marginal veins for 1/2 of length, intermediate veins conspicuous, area between them smooth or sparsely scabrid, glabrous or basally pilulose; callus usually sparsely webbed, hairs less than 1/2 as long as lemma; paleas smooth, minutely bumpy, or scabrid, glabrous or pilulose between keels, keels scabrid, sometimes medially pilulose. Anthers (2–)2.3–3 mm, or vestigial. Fl. and fr. Jun–Aug.
Common in alpine rocky slopes, mountain slopes, meadows among thickets, coniferous, Quercus, and Larix forests on slopes; 3000–5000 m. Qinghai, W Sichuan, SW Xinjiang, Xizang, Yunnan [Afghanistan, Bhutan, India, Nepal, Pakistan].
Poa polycolea is a distinctive and common species of the upper mountains from west to east along the Himalayas, extending northward through Hengduan Shan. It has slender culms and blades, short ligules, and long anthers, or florets, spikelets, or inflorescences that are female. It is quite variable in floret vestiture, and in the east it grades toward P. asperifolia, which has stouter culms with more raised nodes and longer leaf blades and ligules, and P. tangii, which has softer leaves and smooth branches, broader first glumes, and more often blunt lemmas. Infrequently some spikelets have an additional sterile bract above the 2 normal glumes as in the type of P. triglumis.