Leymus simplex

HABIT Perennial; culms solitary. Rhizomes elongated. Culms erect; 15–75 cm long; 1–2.5 mm diam. Culm-internodes distally glabrous, or pubescent. Leaf-sheaths smooth; glabrous on surface. Leaf-sheath oral hairs ciliate; 1–2 mm long. Leaf-sheath auricles absent, or falcate; 0.4–0.8 mm long. Ligule an eciliate membrane; 0.3–0.5 mm long; erose; truncate. Leaf-blades 4–29 cm long; 1–2(–5) mm wide; coriaceous; stiff. Leaf-blade venation with 6–10 secondary veins. Leaf-blade surface ribbed; scabrous; rough adaxially; pilose; sparsely hairy.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 1.5–27 cm long; 4–15 mm wide. Rhachis glabrous on surface, or puberulous on surface; ciliate on margins. Rhachis hairs 0.5–1 mm long. Spikelet packing broadside to rhachis. Rhachis internodes linear; 7–20 mm long.

Spikelets appressed; solitary (or paired at base of raceme). Fertile spikelets pedicelled. Pedicels 1–2(–5) mm long.

FERTILE SPIKELETS Spikelets comprising 3–12 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 16–25 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes collateral; persistent; similar; shorter than spikelet. Lower glume lanceolate; 8–12 mm long; 1 length of upper glume; coriaceous; 1-keeled; 0–1(–3) -veined. Lower glume lateral veins absent, or obscure. Upper glume lanceolate; 8–12 mm long; coriaceous; 1-keeled; 0–1(–3) -veined. Upper glume primary vein absent, or obscure. Upper glume lateral veins absent, or obscure.

FLORETS Fertile lemma lanceolate; 7–12 mm long; coriaceous; without keel; 5 -veined. Lemma apex acute; awned; 1 -awned. Principal lemma awn 2.3–6.5(–12) mm long overall. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 3.7–4.5 mm long.

DISTRIBUTION North America: northwest USA and southwest USA.

NOTES Triticeae. Fl N Amer 2007.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.