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.

Deyeuxia rubescens

HABIT Perennial. Rhizomes elongated. Culms 50–110 cm long. Culm-internodes smooth. Lateral branches lacking. Leaf-sheaths smooth. Ligule an eciliate membrane; 1–3 mm long; lacerate; obtuse, or acute. Collar pubescent. Leaf-blades 2–4 mm wide. Leaf-blade surface scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 4–15 cm long; 1–2.5 cm wide.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 4–5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 1 mm long; 0.25 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein smooth. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 4–5 mm long; 1.1 length of adjacent fertile lemma; membranous; 1-keeled; 1–3 -veined. Upper glume primary vein smooth. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 3.5–4.5 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 4 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.25 way up back of lemma; geniculate; 5–6 mm long overall; clearly exserted from spikelet; with twisted column. Palea 1 length of lemma. Rhachilla extension 1.2 mm long; villous; with 2 mm long hairs.

FLOWER Lodicules 2; 0.6 mm long. Anthers 3; 2.5 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform. Disseminule comprising a floret.

DISTRIBUTION North America: western Canada, northwest USA, and southwest USA.

NOTES Aveneae. Fl Pac NW 1994.

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