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 versicolor

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms 82–100 cm long; 3–4 -noded. Culm-internodes distally glabrous, or pubescent. Culm-nodes glabrous, or pubescent. Leaf-sheaths without keel. Leaf-sheath oral hairs lacking. Leaf-sheath auricles erect; 4–8 mm long. Ligule an eciliate membrane; 5–22 mm long; membranous. Collar glabrous, or pubescent. Leaf-blades conduplicate; 12–27 cm long; 2–5 mm wide. Leaf-blade surface scabrous; rough on both sides.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear, or lanceolate; 17–60 cm long; 1.5–6 cm wide. Primary panicle branches ascending; 4–11.5 cm long. Panicle axis scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1–2.5 mm long; scaberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 2.5–3.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pilose.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 2–3 mm long; 1 length of upper glume; hyaline; without keels; 0–1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume apex acute; muticous, or mucronate, or awned; 1 -awned. Lower glume awn 0–1.2 mm long. Upper glume lanceolate; 2–3 mm long; 0.8 length of adjacent fertile lemma; hyaline; without keels; 0–1 -veined. Upper glume primary vein absent, or obscure. Upper glume lateral veins absent. Upper glume surface asperulous. Upper glume apex acute; muticous, or mucronate, or awned; 1 -awned. Upper glume awn 0–1.2 mm long.

FLORETS Fertile lemma lanceolate; 2.5–3.5 mm long; membranous; without keel; 3 -veined. Lemma surface pubescent; hairy below. Lemma margins ciliate. Lemma apex acute; awned; 1 -awned. Principal lemma awn flexuous; 17–30 mm long overall. Palea 1–1.1 length of lemma; 2 -veined. Palea surface pubescent; hairy on back.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION North America: Mexico. South America: Mesoamericana.

NOTES Eragrostideae. Soderstrom 1994.

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