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.

Muhlenbergia cuspidata

HABIT Perennial; caespitose. Rootstock evident. Culms erect, or geniculately ascending; 20–40 cm long; wiry. Culm-internodes solid; distally pubescent. Lateral branches sparse. Leaf-sheaths keeled; puberulous. Ligule a ciliolate membrane; 1 mm long; truncate. Leaf-blades 5–10 cm long; 1–1.5 mm wide. Leaf-blade surface puberulous; hairy adaxially. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 5–12 cm long; 0.4 cm wide. Primary panicle branches appressed; bearing spikelets almost to the base. Panicle axis scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 1.5 mm long; 1 length of upper glume; membranous; without keels; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 0.5 mm long. Upper glume ovate; 1.5 mm long; 0.5 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 0.5 mm long.

FLORETS Fertile lemma lanceolate; 3 mm long; membranous; without keel; 3 -veined. Lemma midvein scabrous. Lemma surface puberulous; hairy below; hairy on veins. Lemma apex acuminate; mucronate, or awned; 1 -awned. Principal lemma awn 0.5 mm long overall. Palea 1 length of lemma; 2 -veined.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 1–1.2 mm long.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION North America: western Canada, northwest USA, north-central USA, northeast USA, south-central USA, and southeast USA.

NOTES Eragrostideae. Fl Pac NW 1994.

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