紊草 wen cao

Roegneria confusa (Roshevitz) Nevski var. breviaristata Keng, Acta Univ. Nankin. Sci. Nat. 1963(1): 52. 1963; R. confusa subsp. breviaristata (Keng) N. R. Cui.

Culms 30–70 cm tall, 3-noded. Leaf sheath glabrous, but retrorsely pilose at base; leaf blade green, usually involute, 3–7.4 × ca. 0.4 cm, abaxial surface glabrous, adaxial surface scabrous. Spike erect, ca. 10 cm. Spikelets yellowish, green, or purplish green, 10–15 mm excluding awns, with 4 or 5 florets. Glumes narrowly lanceolate, 3-veined or distal glume 5-veined, scabrous along veins, apex long acuminate or distal glume with short awn; proximal glume 4–6 mm; distal glume 6–8 mm. Lemma laxly hirsutulous abaxially; first lemma 9–11 mm; awn reflexed, 13–15 mm, scabrous. Palea equaling lemma, ciliolate along keels distally, apex usually truncate. Fl. and fr. Jul–Aug. 2n = 42*.

* Meadows. Ningxia, Xinjiang.

Elymus confusus var. confusus is distributed in Mongolia and Russia, but has not yet been recorded from China. It differs from var. brevi-aristatus in having the awn of the first lemma about twice as long as the lemma body and in its chromosome number of 2n = 28.