Isoetes butleri
It is native to the eastern United States, where it is scattered and local.[2] It is found almost exclusively on seasonally wet alkaline soils.[3] Common habitats include rocky prairies and glades, most often over limestone.[4] This species is inconspicuous and easily overlooked, due to its superficial similarity to a vegetative grass or sedge.[5] The leaves of Isoetes butleri die back at the end of spring, when its habitat becomes hot and dry.