1.) Morphology and Systematics of the Genus Ptelea
is a genus of trees belonging to the citrus family; it is native to the eastern and southern portions of North America, where it has been used in traditional herbal medicine. The last revision of this genus, in 1962, recognized three species. Two of these were local southwestern species; P. trifoliata
was broadly defined as a widespread and variable species, with five subspecies most of which w...