Muhlenbergia quadridentata

HABIT Perennial; caespitose; clumped densely. Butt sheaths persistent and investing base of culm. Culms 20–70 cm long. Leaf-sheaths without keel. Ligule an eciliate membrane; 2–5 mm long. Leaf-blades involute; 5–15 cm long; 1–3 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear, or lanceolate; 5–20 cm long. Primary panicle branches appressed, or ascending; 2–5 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 4–4.7 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; dissimilar; shorter than spikelet. Lower glume lanceolate, or elliptic; 2–3 mm long; 0.75 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse, or acute. Upper glume elliptic, or oblong; 2.5–4 mm long; 0.6–0.8 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume apex dentate; 3–4 -fid; truncate, or obtuse.

FLORETS Fertile lemma elliptic; 4–4.7 mm long; membranous; without keel; 3 -veined. Lemma surface pilose; hairy at base. Lemma margins ciliate; hairy below. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 5–20 mm long overall. Palea 0.9 length of lemma; 2 -veined. Palea surface pilose; hairy on back.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 2–2.5 mm long.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION North America: Mexico. South America: Mesoamericana.

NOTES Eragrostideae. Fl Nov Gal 1994.

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