Muhlenbergia spiciformis

HABIT Perennial; caespitose. Culms erect; 30–60 cm long. Culm-internodes smooth, or scaberulous; distally glabrous. Leaf-sheaths smooth; glabrous on surface. Ligule a ciliolate membrane; 0.5 mm long. Leaf-blades erect; flat, or involute; 5–10 cm long; 1–2 mm wide. Leaf-blade surface puberulous.

INFLORESCENCE Inflorescence a panicle; embraced at base by subtending leaf.

Panicle contracted, or spiciform; linear; 10–15 cm long. Primary panicle branches appressed; bearing spikelets almost to the base. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

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 pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 1 mm long; 1 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex erose; truncate. Upper glume oblong; 1 mm long; 0.33 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex erose; truncate.

FLORETS Fertile lemma lanceolate; 3 mm long; membranous; without keel; 3 -veined. Lemma surface scaberulous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn flexuous; 10–40 mm long overall. Palea 1 length of lemma; 2 -veined.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION North America: south-central USA and Mexico. South America: Caribbean.

NOTES Eragrostideae. N Amer Fl 1994.

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