[The specific epithet was misprinted as "glabrifloris" in J.] This species is largely restricted to southeastern states, but it extends up the Atlantic coast to Maine (A. Haines, pers. comm.). It usually occurs in native grassland or associated thin woodland. Var. glabriflorus tends to occur on relatively damp soils, especially lowlands in more southern regions. Although glabriflorus is distinct, it has often been confused with other species. The name glabriflorus has often been applied to macgregorii, and this error has persisted in some cases (e.g. much of Ind. in FNA 24). Also, glabriflorus has often been misidentified as canadensis (e.g. in ML). In Ky. there appear to be occasional hybrids with virginicus, hystrix and other species: some colls. from MCLE and WEBS (EKY) may be hybrids with jejunus or villosus (respectively). Further to the southeast, glabriflorus appears to have extensively hybridized with hystrix, forming a distinct variant in the Piedmont of N.Car., S.Car. and Ga.: Elymus hystrix L. var. piedmontanus D.B. Poind. & Weakley (Weakley et al. 2017).