This close relative of meadii occurs in north-central states and adjacent Canada, often on damper sites. It is often difficult to distinguish from meadii and there may be intergradation, but authorities consider the two taxa to be distinct species (FNA 23). Some colls. from Ky, have been determined as tetanica, following older manuals (e.g. F, Cr); colls. from LEWI (A. Cusick at MICH) and ROWA (A. Risk at MDKY) have been particularly convincing. However, most or all colls. have now been redetermined as meadii by R. Naczi or A.A. Reznicek. C. tetanica tends to have narrower spikes than meadii (3-5.8 mm versus 3.5-8 mm), narrower achenes (1.2-1.8 mm versus 1.7-2.5 mm), and more elongated ligules (l/w 0.8-2 versus 0.4-1.2); 2n = 56 versus 52.