Muhlenbergia polycaulis

HABIT Perennial; caespitose. Rhizomes elongated; knotty. Culms slender; 15–40 cm long; wiry. Leaf-sheaths without keel; smooth, or scaberulous. Ligule an eciliate membrane; 0.5–1 mm long; erose, or lacerate. Leaf-blades flat, or conduplicate, or involute; 3–8(–10) cm long; 1 mm wide. Leaf-blade surface scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; interrupted; 3–9 cm long; 0.3–0.6 cm wide.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 2.3–3.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume lanceolate; 1.5–2.5 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 0.2–1.5 mm long. Upper glume lanceolate; 1.5–2.5 mm long; 0.6–0.7 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 2.3–3.5 mm long; membranous; keeled; 3 -veined. Lemma surface villous; hairy below. Lemma apex acute; awned; 1 -awned. Principal lemma awn flexuous; 10–20(–25) mm long overall. Palea 1 length of lemma; 2 -veined. Palea surface villous; hairy on back; hairy below.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 1.5–2 mm long; orange.

FRUIT Caryopsis with adherent pericarp; fusiform; 1.5–2 mm long.

DISTRIBUTION North America: southwest USA, south-central USA, and Mexico.

NOTES Eragrostideae. Gould.

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