Panicum laxiflorum

HABIT Perennial; mat forming. Culms 15–40 cm long. Culm-internodes distally glabrous. Culm-nodes bearded. Lateral branches lacking. Leaves heterophyllous with a basal winter rosette. Leaf-sheaths glabrous on surface, or hirsute; with simple hairs, or reflexed hairs; outer margin hairy. Ligule an eciliate membrane, or a ciliolate membrane. Leaf-blade base broadly rounded. Leaf-blades lanceolate; 7–16 cm long; 3–10 mm wide; yellowish green. Leaf-blade surface glabrous, or pubescent; sparsely hairy. Leaf-blade margins ciliate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; pyramidal; loose; 7–12 cm long; bearing few spikelets. Panicle axis hirsute. Panicle branches hirsute.

Spikelets spreading; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or ovate; dorsally compressed; obtuse; 1.7–2.3 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5 mm long; 0.25–0.33 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1.7–2.3 mm long; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume surface pubescent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1.7–2.3 mm long; 1 length of spikelet; membranous; 5 -veined; pubescent; obtuse. Fertile lemma elliptic; dorsally compressed; 1.5–2 mm long; indurate; shiny; without keel. Lemma margins involute. Palea involute; indurate.

FLOWER Anthers 3.

DISTRIBUTION North America: northeast USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana and Caribbean.

NOTES Paniceae. Gr Texas 1997.

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