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.

Muhlenbergia michisensis

HABIT Perennial; caespitose; clumped densely. Rhizomes absent. Butt sheaths papery; persistent and investing base of culm; with curly dead sheaths. Culms erect; 68–80 cm long. Culm-internodes distally glabrous. Culm-nodes glabrous. Leaf-sheaths 8–14 cm long; longer than adjacent culm internode; without keel; scaberulous. Ligule an eciliate membrane; 4–7 mm long; acuminate. Leaf-blades flat, or conduplicate, or involute; 8.5–20 cm long; 1–3 mm wide. Leaf-blade surface scabrous; rough abaxially; glabrous, or hirsute; sparsely hairy; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 12–17 cm long; 2–4 cm wide. Primary panicle branches spreading; 0.4–3 cm long. Panicle axis scabrous.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled. Pedicels 0.2–1 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 4.5–5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; exceeding apex of florets. Lower glume lanceolate; 4.5–5 mm long; 1 length of upper glume; membranous; dark green; without keels; 1 -veined. Lower glume primary vein pubescent. Lower glume lateral veins absent. Lower glume surface scabrous; pubescent; hairy at base. Lower glume apex acute. Upper glume lanceolate; 4.5–5 mm long; 1.3 length of adjacent fertile lemma; membranous; dark green; without keels; 1(–3) -veined. Upper glume primary vein pubescent. Upper glume lateral veins absent, or obscure. Upper glume surface scabrous; pubescent; hairy at base. Upper glume apex acute.

FLORETS Fertile lemma oblong; 3.5–4 mm long; membranous; without keel; 3 -veined. Lemma midvein ciliolate. Lemma margins ciliolate. Lemma hairs 0.3 mm long. Lemma apex dentate; 2 -fid; with lobes 0.2 mm long; awned; 1 -awned. Principal lemma awn from a sinus; flexuous; 10–15 mm long overall. Palea oblanceolate; 2.8–3.5 mm long; 2 -veined. Palea surface pubescent; hairy on back. Palea apex lobed; 3 -fid.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 2–2.4 mm long; purple.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. Herrera & Peterson 2002.

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