穗发草 sui fa cao

Deschampsia cespitosa (Linnaeus) P. Beauvois subsp. ko-elerioides (Regel) Tzvelev.

Perennial, forming small dense tussocks. Culms erect, 5–40 cm tall, 1–1.7 mm in diam., 1(or 2)-noded. Leaf sheaths loose, glabrous; leaf blades linear, flat or rolled, up to 20 cm, 1–3 mm wide, abaxial surface smooth, adaxial surface with coarse sharp ridges, smooth or scaberulous; ligule acuminate, up to 8 mm. Panicle densely contracted to spikelike, ovoid to oblong, 1–7 cm, brownish purple with golden sheen; branches very short, visible or not. Spikelets 4–6 mm, florets 2, rachilla internode ca. 1 mm; glumes subequal to spikelet, lower glume slightly shorter than or equaling upper glume, 1-veined, upper glume 3-veined, apex acute or obtuse, often lacerate; callus hairs ca. 1/3 lemma length; lemmas 3–4 mm, awned from or near lower 1/4, apex broadly 2-toothed, teeth irregularly lacerate; awn straight or slightly bent, equaling or slightly longer than lemma. Anthers 1.5–2.2 mm. Fl. Jul–Aug.

Damp alpine meadows, wet places near rivers and stream banks; 3500–5100 m. Gansu, Nei Mongol, Qinghai, Xinjiang, Xizang [E Afghanistan, Kashmir, Kazakhstan (Tarbagatai Mountains), Kyrgyzstan, Mongolia, N Pakistan, Russia (S Siberia), Tajikistan (Pamirs), Uzbekistan].

This is a distinctive, high-altitude variant from the Deschampsia cespitosa complex, distinguished by its short, spikelike, purple-brown panicles.

A specimen collected in S Xizang (N of Kumaon, N India) has been assigned to Deschampsia cespitosa subsp. sikkimensis Noltie, which is otherwise known only from India (Sikkim). It is a small plant with compact panicles, close to D. koelerioides, but differing in its pyramidal panicle with the spikelets aggregated into fascicles.