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 seatonii

HABIT Perennial; culms solitary. Rhizomes elongated. Culms erect, or geniculately ascending; 20 cm long. Culm-internodes distally glabrous. Leaf-sheaths longer than adjacent culm internode; smooth; glabrous on surface. Ligule an eciliate membrane; 2–3 mm long. Leaf-blades flat, or involute; 3–8 cm long; 1 mm wide. Leaf-blade surface puberulous; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 10–15 cm long. Primary panicle branches ascending, or spreading; 4–7 cm long. Panicle axis smooth. Panicle branches stiff; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 4 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 1 mm long; 0.75 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume oblong; 1.5 mm long; 0.4 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex obtuse.

FLORETS Fertile lemma lanceolate; 4 mm long; membranous; without keel; 3 -veined. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn from a sinus; flexuous; 10–15 mm long overall. Lateral lemma awns 1–2 mm long. Palea 1 length of lemma; 2 -veined.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. N Amer Fl 1994.

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