Panicum portoricense

HABIT Perennial. Culms erect; 15–30 cm long. Lateral branches ample. Leaves heterophyllous with a basal winter rosette. Leaf-sheaths glabrous on surface, or puberulous. Ligule absent. Leaf-blades lanceolate; 2–5 cm long; 3–6 mm wide. Leaf-blade surface glabrous, or puberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 2–4 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; dorsally compressed; obtuse; 1.5–1.6 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; clasping; 0.33 length of spikelet; membranous; without keels. Lower glume apex truncate, or obtuse. Upper glume obovate; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume surface puberulous. Upper glume apex obtuse.

FLORETS Basal sterile florets barren. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 7 -veined; puberulous; obtuse. Fertile lemma elliptic; dorsally compressed; 1.5–1.6 mm long; indurate; without keel. Lemma margins involute. Palea involute; indurate.

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

NOTES Paniceae. Man US Grass 2004.

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