This is a largely Ozarkian species, but it is also known from a few scattered locations across southeastern states, usually in rocky woods on base-rich soils. Variation needs further attention; 2n = 18 and 36 (FNA 20). The only record from Ky. may be a coll. from HARD (Cranfill & Medley 1981; M). The coll. cannot now be located, and the area has been revisited with no success. Nevertheless, Cronquist (Cr) may have confirmed the coll. since he included w. Ky. in the range of radula; see also FNA 20. Although generally classified with nemoralis, radula appears similar to some species of the Triplinerviae (especially rupestris; see W).