GrassBase - The Online World Grass Flora


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

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

Pleuropogon refractus

HABIT Perennial. Rhizomes elongated. Culms 100–150 cm long. Leaf-sheaths 10–20 cm long; glabrous on surface, or pubescent. Ligule an eciliate membrane; 1.5–3.5 mm long. Leaf-blades 10–30 cm long; 3–7 mm wide. Leaf-blade apex abruptly acute; simple, or apiculate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 15–20 cm long; bearing few fertile spikelets; bearing 5–12 fertile spikelets on each. Spikelet packing broadside to rhachis; distant.

Spikelets deflexed; solitary. Fertile spikelets pedicelled. Pedicels linear; 1–2 mm long.

FERTILE SPIKELETS Spikelets comprising 8–12 fertile florets; with diminished florets at the apex. Spikelets linear, or oblong; laterally compressed; 20–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 3 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume oblong; 4–5 mm long; 0.6–0.7 length of upper glume; hyaline; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex erose; acute. Upper glume oblong; 5–7 mm long; 0.8 length of adjacent fertile lemma; hyaline; without keels; 3 -veined. Upper glume apex erose; acute.

FLORETS Fertile lemma ovate; 7–8 mm long; chartaceous; without keel; 7 -veined. Lemma surface asperulous; rough on veins. Lemma apex erose; obtuse, or acute; awned; 1 -awned. Principal lemma awn 5–12 mm long overall. Palea 1 length of lemma; 2 -veined. Palea keels winged; conspicuously winged; with toothed wings; scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; united; oblong; fleshy; truncate. Anthers 3; 3–4 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

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

NOTES Meliceae. Benson.

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