Digitaria simpsonii

HABIT Annual. Culms decumbent; 80–120 cm long; rooting from lower nodes. Leaf-sheaths loose; keeled; hirsute; with tubercle-based hairs. Ligule an eciliate membrane. Leaf-blades 7–30 cm long; 3–5 mm wide. Leaf-blade surface hirsute; with tubercle-based hairs.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 6–8; digitate; unilateral; 10–13 cm long. Central inflorescence axis 4–6 cm long. Rhachis angular.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels angular; pubescent.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; acute; 3 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume surface glabrous. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 7 -veined; glabrous; acute. Fertile lemma elliptic; 3 mm long; cartilaginous; much thinner on margins; pallid; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION North America: southeast USA.

NOTES Paniceae. N Amer Fl 1994.

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