If one species had to be chosen to preserve and restore, perhaps it should be cottonwood. Cottonwood-willow forests, where they exist and are healthy, indicated the presence of a viable riparian area, which is in turn the key to conserving great proportions of our native species. A reflection of the dire status of our riparian systems is that the Sonoran cottonwood-willow and Sonoran mesquite-cottonwood forests.