Columbia University, the University of Maryland, and theSmithsonian Institution are working on visual recognition software to help identify species from photographs. Leafsnap is the first in a series of electronic field guides being developed to demonstrate this new technology. This free mobile app helps identify tree species from photographs of their leaves and contains beautiful high-resolution images of their flowers, fruit, petiole, seeds, and bark. Leafsnap currently includes the trees of New York City and Washington, D.C., and will soon grow to cover the trees of the entire continental United States.

Leafsnap turns users into citizen scientists, automatically sharing images, species identifications, and geo-coded stamps of species locations with a community of scientists who will use the stream of data to map and monitor the ebb and flow of flora nationwide.