Plants of indefinite duration; not rhizomatous. Culms 80-120 cm,
erect or decumbent and rooting at the lower nodes, not branching at the aerial
nodes. Sheaths hirsute, with papillose-based hairs, those of the innovation
sheaths compressed-keeled; ligules 1-2 mm; blades 7-30 cm long,
3-5 mm wide, flat, pilose above and below. Panicles with 6-8 spikelike
primary branches on 4-6 cm rachises; primary branches 8-13 cm, axes triquetrous,
narrowly winged, wings less than 1/2 as wide as the midribs, lower and middle
portions of the branches with spikelets in appressed, unequally pedicellate
pairs; secondary branches rarely present; axillary inflorescences
not present; pedicels not adnate to the branch axes. Spikelets
about 3 mm, elliptic lanceolate, acute. Lower glumes absent or minute
and hyaline; upper glumes 7-9-veined, glabrous or obscurely pubescent;
lower lemmas 7-9-veined, glabrous or obscurely pubescent; upper lemmas
elliptic, yellow or gray, becoming purple at maturity, slightly apiculate. 2n
= unknown.
Digitaria simpsonii is a rare species, known only from sandy fields in
Florida.