GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Leymus pacificus

HABIT Perennial; culms solitary. Rhizomes elongated. Culms decumbent; 10–20 cm long. Ligule an eciliate membrane; truncate. Leaf-blades involute; 2–4 mm wide; coriaceous; stiff. Leaf-blade surface ribbed. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; linear, or oblong; bilateral; 2–5 cm long. Rhachis glabrous on surface; glabrous on margins. Spikelet packing broadside to rhachis. Rhachis internodes linear.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–6 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 12–15 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes collateral; persistent; similar; shorter than spikelet, or reaching apex of florets, or exceeding apex of florets. Lower glume subulate; coriaceous; 0 -veined. Lower glume lateral veins absent. Upper glume subulate; coriaceous; 1 -veined. Upper glume primary vein absent. Upper glume lateral veins absent.

FLORETS Fertile lemma lanceolate; 10 mm long; coriaceous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma apex acuminate to setaceously attenuate. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

DISTRIBUTION North America: southwest USA.

NOTES Triticeae. Man US Gr 1997.

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