This is probably widespread in east-central states, but there has been much confusion with the related species, capillare and especially philadelphicum (Hitchcock & Chase 1950; FNA 25). Some intergradation with both of those species may occur, and gattingeri is sometimes treated as a segregate of either one; see Haines et al. (2011) for a northeastern perspective. In Ky. gattingeri is usually distinct and typically occurs on relatively fertile soils in habitats intermediate between the damp cultivated soils typical of capillare and the seasonally dry or rocky ground typical of philadelphicum and flexile.