Mapping here is provisional. Although combined with tenuis by some authors (Cr), interior it is still generally recognized as a separate taxon. It is widespread in prairies from the Great Plains to Mo., Ill. and Ind., but uncommon to rare in most of the glaciated Ohio Valley, where it is often confused with related species. Compared to tenuis, interior grows in more seasonally dry and open habitats on varied types of soil. J. interior has been mapped in Ky. by FNA 22, and R. Naczi has identified colls. from marshy shorelines and depressions in lowlands of BOYD, CAMP and GRNP. Colls. of R. Athey from BALL, FULT, GRAV and MCRA all have dubious identifictions and need to be rechecked. Compared to other species of the tenuis group, interior has few distinctive characters (F; Braun 1967; FNA 22; Y). It appears to differ from tenuis only in its shorter, stramineous auricles (ca. 0.5-1 mm versus 1-4 mm), acute-acuminate bracteoles (versus blunt-acute), and its more open inflorescences (sometimes suggesting anthelatus or secundus).