Plants cespitose, dense and cylindrical to obpyramidal above. Culms
40-210 cm; internodes glaucous or not; branches erect to ascending,
usually straight, sometimes arching. Sheaths usually smooth, rarely somewhat
scabrous; ligules 0.2-1 mm, ciliate, cilia 0.2-1.3 mm; blades
11-52 cm long, 1.7-6.5 mm wide, smooth and glabrous or sparsely to densely pubescent
with spreading hairs. Inflorescence units 6-195 per culm; subtending
sheaths (2.1)3.1-4.6(6.7) cm long, (1.7)3-3.8(5.6) mm wide; peduncles
usually (1)4-6(30) mm, with 2-7 rames; rames (0.5)1.7-2.8(4.4) cm, sometimes
exserted at maturity, pubescence sparse basally and increasing in density distally
within each internode. Sessile spikelets (2.6)3.5-3.8(4.7) mm; callus
hairs 1-3 mm; keels of lower glume usually smooth below midlength,
scabrous distally; awns 6-21 mm; anthers 1(3), 0.6-1.5 mm, yellow
or purple. Pedicellate spikelets vestigial to absent. 2n = 20.
Andropogon virginicus is native from the southeastern United States to
northern South America, but has become established outside its native range in California, Hawaii, Japan, and Australia.
Three varieties are recognized, two of which contain morphologically distinct
variants. Andropogon virginicus hybridizes with A.
glomeratus and A. longiberbis
(Campbell 1986).
Culms 70-170 cm. Leaves green, sometimes slightly
glaucous. Inflorescence units usually with 2 rames; subtending sheaths
(1.7)2.4-3.1(4) mm wide; peduncles (1) 4-9 (30) mm; rames (1.3)1.5-2.3(3)
cm.
Andropogon virginicus var. decipiens grows in flatwoods, scrublands,
and disturbed sites, such as roadsides and cleared timberlands, of the southeastern
coastal plain.
Culms tufted, 5-15 dm, branched above, mostly glabrous and often glaucous, the uppermost nodes sometimes sparsely villous; lvs often pilose on the sheath and ligule, the blade 3-8 mm wide; uppermost lvs spathe-like, enclosing the short (2-10 mm) peduncle and base of the few-many paired racemes, these 2-3 cm, with slender, flexuous, long-villous rachis; fertile spikelet 3-5 mm, shorter than the long-villous sterile pedicel, but longer than the internode just above it, the straight awn 1-2 cm; stamen mostly solitary; sterile spikelet none, or a delicate narrow glume to 2 mm; 2n=20. Our two principal vars. are very distinct northward, but pass freely into each other along the coastal plain from Md. southward through a series of intermediate forms often called var. glaucopsis (Elliott) Hitchc. Typical material differs as follows:
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.