was placed on the endangered species list, its Hiwassee River population had declined 50% in eight years. Since then it has declined another 40% and all subpopulations are likely to become extinct within 50 years. The other population on the Ocoee River was composed of about 500 plants growing in a habitat affected by nearby mining operations, as well as power production. It is also located in an area that is subjected to trampling associated with whitewater rafting recreation on the river. Despite these threats, the Ocoee population, recently counted at 593 plants, is considered to be secure for the time being. Conservation activities include propagation of the plant in greenhouses. This is made difficult by the infestation of the greenhouse plants by the powdery mildew Erysiphe cichoracearum. The mildew is not present in the wild populations. Competing vegetation has been increasing yearly, and this is likely causing a negative impact. The Cherokee National Forest implemented a plan to remove poison ivy from aster sites, and though this was effective it was not feasible. Mechanical and chemical means are used to remove the vegetation. References External links USDA Plants Profile Astereae Flora of Tennessee Polk County, Tennessee