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.

Elymus laxiflorus

HABIT Perennial; caespitose; clumped densely. Culms erect, or geniculately ascending; 50–70 cm long; 1.5 mm diam.; 4–5 -noded. Leaf-sheaths mostly shorter than adjacent culm internode; smooth; glabrous on surface. Ligule an eciliate membrane; 0.5 mm long. Leaf-blades flat, or involute; 10 cm long; 3 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 10–16 cm long; 6–8 mm wide. Rhachis flattened; glabrous on surface, or puberulous on surface; scabrous on margins. Spikelet packing broadside to rhachis; lax; regular; 2 -rowed. Rhachis internodes 8–15(–20) mm long.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 6–9 fertile florets; with diminished florets at the apex. Spikelets laterally compressed; 16–22 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1–1.5 mm long; pubescent. Floret callus pubescent.

GLUMES Glumes persistent; similar; subequal in width; shorter than spikelet. Lower glume lanceolate, or oblong; 4 mm long; coriaceous; much thinner on margins; without keels; 3 -veined. Lower glume surface glabrous. Lower glume apex acuminate; muticous. Upper glume lanceolate, or oblong; 6–7 mm long; coriaceous; with membranous margins; without keels; 5 -veined. Upper glume surface glabrous. Upper glume apex acuminate; muticous.

FLORETS Fertile lemma lanceolate; 5–10 mm long; coriaceous; without keel; 5 -veined. Lemma surface pubescent. Lemma apex acute, or acuminate; muticous, or awned; 1 -awned. Principal lemma awn 1–2 mm long overall. Palea 1.1 length of lemma; 2 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 3–4 mm long; yellow. Stigmas 2. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex; apex unappendaged. Hilum linear.

DISTRIBUTION Asia-temperate: China.

NOTES Triticeae. Chen 2001.

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