The Spring White (Pontia sisymbrii) is the easiest species to distinguish of the three Pontia whites; the dark vein markings on the hindwing underside are not connected laterally, and it occurs only in montane woodlands and extreme northern Alberta. Females have a yellow flush to them, unlike the Western and Checkered Whites. Alberta populations are the nominate subspecies. Mountain populations are referable to subspecies flavitincta, and our northern boreal populations are the recently-described subspecies beringiensis Guppy & Kondla (Guppy & Shepard 2001).