[Wikipedia] Range, Threats: Streptanthus howellii is an uncommon species of flowering plant in the mustard family known by the common name Howell's jewelflower.[1] It is endemic to the Klamath Mountains of southern Oregon and northern California. It grows in mountain forests on serpentine soils. This rare plant is threatened by wildfire suppression; it would be more common if its habitat were allowed its natural fire regime.[2] It is also threatened by mining operations.[3] (link added by Mary Ann Machi)