Plants of indefinite duration; sometimes stoloniferous. Culms with
erect portion 10-85 cm, long-decumbent, rooting and branching at the lower nodes.
Sheaths with papillose-based hairs or the upper sheaths glabrous; ligules
1-4 mm; blades 3-14 cm long, 2-9 mm wide, mostly glabrous but the adaxial
surfaces with papillose-based hairs basally. Panicles with (2)3-6 spikelike
primary branches, these digitate or a few solitary branches below; lowest
nodes glabrous or with hairs less than 0.4 mm; primary branches 6.5-21
cm long, 0.6-1.3 mm wide, axes winged, wings at least 1/2 as wide as the midribs,
lower and middle portions with spikelets in unequally pedicellate pairs, pedicels
not adnate to the branches; secondary branches absent; shorter pedicels
about 0.2 mm; longer pedicels to 2 mm. Spikelets 2.6-3.7 mm, spikelet
pairs dimorphic in their pubescence and venation pattern of the lower lemmas.
Lower glumes absent or to 0.9 mm, deltoid or bifid; upper glumes
1.7-2.8 mm, 1/2-3/4 as long as the spikelets, 3-veined; lower lemmas
7-veined, veins smooth; lower lemmas of shortly pedicellate spikelets
with 3 equally spaced, glabrous or shortly pubescent central veins, lemma margins
and the region between the 2 lateral veins with appressed or spreading, 0.5-1
mm hairs; lower lemmas of long-pedicellate spikelets with unequally spaced
veins, midvein well-separatedfrom the 3 lateral veins, lateral veins crowded
together near the margins, lemma margins and the region between the 2 inner
lateral veins hairy with appressed or strongly divergent, 1-2 mm hairs, sometimes
also with longer, glassy yellow hairs; upper lemmas of all spikelets
usually yellow or gray, sometimes light brown, at maturity; anthers 0.5-0.6
mm. 2n = 54, 72.
Digitaria bicornis is a common species on the sandy coastal plain of
the southeastern United States. Its range extends through Mexico to Costa Rica
and northern South America, as well as to the West Indies. The Californian record
reflects a 1926 collection; the species is not known to be established in the
state.