Elymus shandongensis B. Salomon

This species has long been misclassified by some taxonomists in China as Elymus ×mayebaranus (Honda) S. L. Chen (Agropyron ×may-ebaranum Honda; Roegneria ×mayebarana (Honda) Ohwi ex Keng & S. L. Chen). The true E. ×mayebaranus is found only in Japan; it is a highly sterile natural hybrid between the hexaploid (2n = 42) parents E. humidus (Ohwi & Sakamoto) A. Löve (A. humidum Ohwi & Sakamoto) and E. tsukushiensis Honda.

Culms laxly tufted, erect or slightly decumbent at base, 60–90 cm tall. Leaf sheath usually glabrous; ligule ca. 6.5 mm; leaf blade flat or involute at margin, 10–25 × 0.4–0.8 cm, both surfaces scabrous or adaxial surface smooth. Spike erect or slightly curved, 8–20 cm. Spikelets 1 per node, 13–19 mm excluding awns, with 5–8 florets. Glumes oblong-lanceolate, 5–7-veined, apex acute or pointed; veins robust, scabrous; proximal glume 5–7 mm; distal glume 7–9 mm. Lemma oblong-lanceolate, subglabrous abaxially, margin membranous; first lemma 9–10 mm; callus pubescent along lateral side; awn erect, (12–) 20–30 mm, scabrous. Palea subequaling lemma, wingless and shortly setiform ciliate along keels. Fl. and fr. Jul–Aug. 2n = 28*.

* Mountain slopes, roadsides. Anhui, Guizhou, Henan, Hubei, Jiangsu, Shaanxi, Shandong, Taiwan, Zhejiang.

Roegneria shandongensis (B. Salomon) J. L. Yang et al.