This occurs only on calcareous slopes along larger streams in s. Ky., c. Tenn., n. Ala. and n. Ga. It has been largely overlooked until recent decades, partly due to confusion with the more western species, A. grandiflora (Benth.) Pennell. Reports of grandiflora from Ky. appear to have been erroneous (M), but that species is known from s. Ill. and ne. Ark. Without flowers or fruits, patula can be distinguished from other species in Ky. by its sparse stem pubescence (versus dense in virginica or glabrous in the others); leaves are coarsely serrate up to the inflorescence base (resembling Dasistoma), with relatively prominent stramineous veins on lower surface. In Tenn., Cunningham (2000) showed that patula is a hemiparasite associated with Ostrya, Carpinus and Quercus rubra; Cornus florida and other species were also potential hosts. However, dense Cercis may suppress Aureolaria.