This annual occurs mostly from Mo. and Kans. to La. and Tex. East of the Mississippi it is rare and often presumed to be adventive (W), but it is known from a few remnants of native grassland in Tenn. (Ch; D. Estes, pers. comm.). There are only four known Ky. colls., all in localities where native grassland used to occur (1) R. Athey 379 (MUR), 22 Sep 1968, Mayfield-Metropolis Rd. off Hwy. 62; (2) R. Athey 3804 (MUR), 4 Sep 1977, 0.8 miles on Metropolis-Mayfield Rd. from Ky. 1490; (3) G.P. Johnson #1055 (WKU), 15 Sep 1979; EDMO-BARR Co. line on US31W, cedar glade; (4) C. Williams to R. Seymour (JC for EKY), 28 Aug 2011, HART, roadside north of Munfordville. There has been some confusion with Heterotheca camporum and H. villosa.