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 uniflora

HABIT Perennial; caespitose. Stolons absent. Culms erect; slender; 35–50 cm long. Ligule a fringe of hairs. Leaf-blades involute; 2–10 cm long; 1–2 mm wide. Leaf-blade surface glabrous, or puberulous. Leaf-blade margins ciliate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 25–35; borne along a central axis; unilateral; 0.8–0.9 cm long; bearing 1 spikelet; bearing 1 fertile spikelets on each. Central inflorescence axis 15–25 cm long; tip subulate. Rhachis deciduous from axis; subterete; terminating in a barren extension; extension subulate; extension 4 mm long. Spikelet packing broadside to rhachis. Raceme-bases brief.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 7–8 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes similar; exceeding apex of florets; similar to fertile lemma in texture. Lower glume lanceolate; 3–4 mm long; 0.4–0.5 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 7–8 mm long; 1–1.2 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 6 mm long; membranous; keeled; 3 -veined. Lemma surface glabrous. Lemma apex entire; acute; muticous. Palea 5 mm long; 0.8 length of lemma. Rhachilla extension glabrous. Apical sterile florets 1 in number; barren; rudimentary. Apical sterile lemmas awned; 1 -awned. Apical sterile lemma awns 1–4 mm long.

FLOWER Anthers 3; 2.5–3 mm long; yellow.

FRUIT Caryopsis with adherent pericarp; ovoid; 3 mm long.

DISTRIBUTION North America: south-central USA and Mexico.

NOTES Cynodonteae. Gould.

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