The Bromus carinatus complex comprises several cleistogamous taxa that have been recognized at a variety of taxonomic levels. Our study focused on three taxa: B. carinatus s.s., B. marginatus, and B. polyanthus, that have received varied taxonomic treatment. We mapped the collection sites of 673 specimens belonging to these taxa to determine whether their geographic distribution would support their recognition as species. We examined the characters customarily used to distinguish among the three entities: longevity, blade width, awn length, sheath vestiture, and lemma vestiture. The geographic data do not support the value of blade width as a taxonomic character but provide some support for use of awn length and the two vestiture characters. Of the three taxa, B. polyanthus, characterized as having glabrous sheaths and lemmas and, usually, short awns, was the most geographically distinct taxon. Bromus carinatus sensu stricto and B. marginatus showed some separation, the former being primarily a coastal taxon and the latter primarily an inland taxon. Based on our observations and published molecular data, we propose that B. carinatus and B. marginatus be treated as B. carinatus var. carinatus and B. carinatus var. marginatus (Nees ex Steud.) Barkworth & Anderton, comb. nov. respectively, and that B. polyanthus be treated as a species.