1. Disk cylindrical, longer than the rays; rays less than 2 (–2.5) cm long; pappus of 1–2 tiny teeth.
1. Disk hemispherical (or even nearly spherical) to short-cylindrical, much shorter than the rays; rays ca. 2.5–3.5 (–4.5) cm long; pappus absent.
All species found in Ratibida
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. May 24, 2017. http://michiganflora.net/genus.aspx?id=Ratibida.