This small-headed species is centered in the Ozark region of Okl., Mo., Kans., Iowa and Ill. It is mostly diploid (2n = 16) but occasional polyploids (2n = 32, 48) have been found, especially to the northeast of its core range. A coll. from BULL (KY) appears to be this species, and appears similar to hexaploid colls. from further west (J.C. Semple, pers. comm.): C.R. Gunn #587, 24 Oct 1955, Bernheim Forest, path around Lake Nevin at Cove. Further investigation of this record is needed. However, it may be difficult to distinguish this species from S. juniperinum where ranges overlap (Semple et al. 1995).