光穗旱麦草 guang sui han mai cao

Triticum bonaepartis Sprengel, Erster Nachtr. Bot. Gart. Halle, 40. 1801; Agropyron bonaepartis (Sprengel) T. Durand & Schinz; A. patulum Trinius, nom. illeg. superfl.; A. turkes-tanicum Gandoger; Eremopyrum bonaepartis var. turkestani-cum (Gandoger) Tzvelev; Triticum patulum Willdenow, nom. illeg. superfl.

Culms geniculate and somewhat purple tinged near base, 5–30 cm tall, pubescent below spike. Leaf sheath not inflated on upper leaves, or slightly dilated on uppermost leaf, glabrous or rarely puberulent, scabrous; leaf blade green, 0.2–0.5 cm wide, scabrous. Spike green or faintly colored, ovoid lobed, 2–4.5 × 1.5–2.5(–2.8) cm. Spikelets divergent, pectinately arranged, closely pressed to each other, lax at maturity, 12–15 mm, with 3–5 florets, glabrous. Glumes linear, laterally strongly compressed, 9–14 mm, shorter than spikelet, apex gradually tapering to subulate tip. Lemma linear-lanceolate, 12–14 mm, glabrous, apex gradually tapering to awn 1.5–3 mm. Palea shorter and narrower than lemma, shortly thickly ciliate along keels, apex 2-dentate. Fl. and fr. Apr–May.

A weed in desert and semi-desert zones. Xinjiang [Kazakhstan, Kyrgyzstan, Pakistan, Russia, Turkmenistan, Uzbekistan; E Mediterranean region].