Panicum dichotomum

HABIT Perennial; caespitose. Rootstock evident. Culms slender; 20–80(–100) cm long. Culm-nodes glabrous, or bearded. Lateral branches fastigiate. Leaves basal and cauline; heterophyllous with a basal winter rosette. Leaf-sheaths outer margin hairy. Ligule an eciliate membrane, or a fringe of hairs; 0.2–1 mm long. Leaf-blades 4–12(–15) cm long; 3–10(–13) mm wide. Leaf-blade surface glabrous, or pilose. Leaf-blade margins glabrous, or ciliate; hairy at base. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 3–8(–10) cm long. Primary panicle branches spreading.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or obovate; dorsally compressed; 1.5–2.4 mm long; falling entire.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.25–0.33 length of spikelet; membranous; without keels; 3 -veined. Lower glume apex obtuse. Upper glume oblong; 0.7–0.8 length of spikelet; membranous; without keels; 7–9 -veined. Upper glume surface glabrous, or puberulous. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; oblong; 1 length of spikelet; membranous; 7–9 -veined; glabrous, or puberulous; obtuse. Fertile lemma oblong; dorsally compressed; 1.5–2.4 mm long; indurate; pallid; without keel. Lemma margins involute. Lemma apex obtuse. Palea involute; indurate.

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

NOTES Paniceae. Gould.

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