Rugelia nudicaulis (Rugel's Indian plantain or Rugels ragwort), the sole species of the genus Rugelia, blooms in summer. It is a wildflower endemic to higher elevations in the Great Smoky Mountains. It is a rare species in Tennessee. First placed in the genus Senecio, then moved to Cacalia it was finally placed in a genus of its own, Rugelia. Genetic diversity in this plant, assessed using allozymes, is so low that the species may not survive changing environmental conditions.