Plants cespitose; cylindrical to oblong and more or less open in the
upper portion. Culms 50-100(150) cm; internodes green, sometimes
somewhat glaucous just below the node; branches mostly erect, straight.
Sheaths not scabrous; ligules 0.2-0.6 mm, ciliate, cilia 0.3-0.6
mm; blades 11-50 cm long, 2-5.5 mm wide, sparsely to densely pubescent,
most hairs appressed. Inflorescence units 7-97 (usually about 45) per
culm; subtending sheaths (2.5)3-4.5(6) cm long, (2.5)3.2-4.1(5.5) mm
wide; peduncles (1)3-4(13) mm, with 2(3) rames; rames (1.3)1.8-2.6(4)
cm, not exserted at maturity, pubescence increasing in density distally within
each internode. Sessile spikelets (3.5)4.1-4.5(5) mm; callus hairs
1.5-5 mm; keels of lower glumes scabrous only above the midpoint; awns
10-21 mm; anthers 1, 0.9-1.6 mm, yellow. Pedicellate spikelets
vestigial or absent. 2n = 20.
Andropogon longiberbis grows in sandy or rocky soils of roadsides, dunes,
sandhills, pinelands, and fields, from the southeastern United States to the
Bahamas. It resembles A. tracyi, but
usually differs in having more densely pubescent blades and a less slender appearance.
Andropogon longiberbis appears to hybridize with both
A. virginicus var. virginicus
and A. glomeratus var.