Arundo lapponica Wahlenberg, Fl. Lapp. 27. 1812; Cala-magrostis lapponica (Wahlenberg) Hartman.

Perennial, loosely tufted, shortly rhizomatous. Culms erect from a geniculate base, 60–130 cm tall, 2–3 mm in diam., smooth, 3-noded. Leaf sheaths smooth; leaf blades flat or involute, 10–30 cm, 2–6 mm wide, adaxial surface loosely pubescent, abaxial surface scabrid; ligule 2–4(–6) mm, lacerate. Panicle loosely contracted, (5–)10–25 × 2–3(–8) cm; branches erect or ascending, 1–3(–4) cm, scabrid, lower 1/3 bare. Spikelets 4–6 mm, purplish brown or yellowish green; glumes ovate-lanceolate, subequal, 4–5 mm, lower glume 1-veined, upper glume 3-veined, scabrid on upper back and veins, apex acuminate; callus hairs 3/4–4/5 length of lemma; lemma 3–4(–5) mm, apex denticulate; awn arising from lower 1/3 of lemma, ca. 3 mm, weakly geniculate, slightly twisted; palea 2/3 as long as lemma; rachilla 1–1.5 mm, including hairs 3–4 mm. Anthers ca. 2 mm. Fl. Jul–Aug.

Grassy slopes, forests, among shrubs, especially along river banks; 400–4100 m. Gansu, Heilongjiang, Nei Mongol, Sichuan, Xinjiang, Xizang [Mongolia, Korea, Russia; Europe, North America].