Calamagrostis dubia (Scribner & Tweedy) Scribner ex Vasey nom. illeg.

Calamagrostis dubia (Scribner & Tweedy) Scribner ex Vasey nom. illeg. is a synonym sensu TROPICOS of:

Calamagrostis canadensis (Michaux) Palisot de Beauvois var. canadensis, an accepted variety name sensu FNA Ed. Comm., 2007.