Southeastern Alaska Distribution: Known only from Yakutat Bay.
Habitat: From sea level to the subalpine in wet habitats, swamps, meadows, ponds, seeps, lakes or streams.
Comments: The species is represented in the region by a single report of each of two varieties: C. polygamum var. longinerve was reported by Stair (1947), and C. polygamum var. minus by Cardot and Theriot (1902). The species is rare throughout Alaska.