Iris tridentata is a species in the genus Iris, it is also in the subgenus of Limniris and in the 'Iris series Tripetalae. It is a rhizomatous perennial. It has the common name of Savannah Iris or Bay Blue-flag Iris Note, normally Iris versicolor is commonly called 'Blue flag iris'. and occasionally Purple Flag. Note, Iris germanica can also be called 'Purple Flag'. 'Tridentata' means three toothed iris in Latin. It was first published by Pursh in 'Flora Americae Septentrionalis' (translated as Systematic Arrangement and Description of the Plants of North America) on December 1813.