This southeastern species occurs mostly on clayey soils of the lower Mississippi Valley (FNA 25, K). It is locally abundant in seasonally wet (xerohydric) remnants of the original grasslands across this region. Ky. records are mostly from the Mississippian Embayment; the few eastern records are mostly from along or near railroads, and may be partly adventive. Hybrids with flavus have been well documented only west of the Mississippi River (T. Witsell, pers. comm.).