The narrowleaf evening primrose is found only in the eastern Uinta Mountains of Utah and on Diamond, Cold Spring, and Douglas Mountains of northwestern Colorado. This beautiful wildflower, with bright yellow flowers that turn reddish orange as they age, grows only in ephemeral stream beds and shallow depressions in forest meadows. This rare habitat type is especially sensitive to disturbance, and almost every known population of this plant is threatened by excessive livestock trampling and off-road vehicles. In April 2006, Center for Native Ecosystems petitioned the U.S. Fish and Wildlife Service to list the narrowleaf evening primrose as a Threatened or Endangered Species.