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.

Bouteloua eludens

HABIT Perennial. Butt sheaths papery. Culms slender; 35–60 cm long. Leaf-sheaths outer margin glabrous, or hairy. Ligule an eciliate membrane; lacerate. Leaf-blades flat; 5–15 cm long; 1–3 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 10–20; borne along a central axis; cuneate; unilateral; 0.7–1.1 cm long; bearing few fertile spikelets; bearing 3–5 fertile spikelets on each. Central inflorescence axis 7–10 cm long; tip subulate. Rhachis deciduous from axis; angular; terminating in a barren extension; extension subulate. Spikelet packing broadside to rhachis.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 6–7 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 5–6 mm long; 0.8–0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface pubescent. Lower glume apex acute to setaceously attenuate. Upper glume lanceolate; 6–7 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface pubescent; hairy generally. Upper glume apex acute to setaceously attenuate.

FLORETS Fertile lemma ovate; 6–7 mm long; coriaceous; keeled; 3 -veined. Lemma surface pubescent. Lemma apex lobed; 3 -fid; with linear lobes; with lobes 0.5–2 mm long; mucronate; 2 -awned (mucros). Palea surface pubescent; hairy on back; hairy above. Rhachilla extension glabrous. Apical sterile florets 1 in number; barren; oblong; 5–6 mm long. Apical sterile lemmas pubescent; lobed; 4 -fid; muticous, or awned; 3 -awned. Apical sterile lemma awns 0.5–5 mm long; ciliate (below).

FRUIT Caryopsis with adherent pericarp; obovoid; 5 mm long. Embryo 0.5–0.75 length of caryopsis.

DISTRIBUTION North America: southwest USA and Mexico.

NOTES Cynodonteae. Gould.

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