六棱大麦 liu leng da mai

Hordeum vulgare Linnaeus subsp. agriocrithon (A. E. Åberg) Å. Löve.

Plants annual. Culms erect, 60–90 cm, smooth, glabrous. Leaf sheath usually glabrous; ligule 1–2 mm, membranous; auricles present, lanceolate; leaf blade flat, 10–15(–20) × 1–1.5 cm. Spike hexastichous, dense; rachis brittle. Spikelets all sessile, fertile, and similar. Glumes 5–6 × ca. 1 mm, densely puberulent; awn slender, ca. 10 mm. Lemma to 14 mm; awn ca. 15 mm. Caryopsis oblong, ca. 12 mm. Fl. and fr. Jun–Sep. 2n = 14.

Usually a weed in fields of Hordeum vulgare. Qinghai, Sichuan, Xizang [C and SW Asia, E Mediterranean region].