AT THE SMITHSONIAN

A New App Called Leafsnap

Senior Editor

May 13, 2011

In the summer of 2009, I had the pleasure of writing about John Kress, a research botanist at the Smithsonian’s National Museum of Natural History, and his efforts to create a DNA barcode for all 25o plant species on Plummers Island, a 12-acre island in the Potomac River here in Washington, D.C. At the time, Kress spoke about a day when citizen scientists, even schoolchildren, would be able to identify plants with handheld DNA sequencers. They would be able to upload the barcode to a smartphone in order to access an online encyclopedia with basics about the species, botanical art and anecdotal information, he explained.

The botanist’s vision seemed so futuristic, but now, just two years later, it is beginning to come to fruition. In fact, Columbia University, the University of Maryland and the Smithsonian Institution have announced that Leafsnap, an iPhone, iPad and Android app that will identify a plant based on a leaf’s silhouette, will be released this summer.

The mobile app uses visual recognition technology to identify the species of a plant based on a photograph of one of its leaves. Each leaf photograph is cross-referenced with a leaf-image library, which Kress helped compile, based on several measurements of the leaf’s outline. The user then gets a ranked list of the leaf’s closest matches, as well as other information about the species.

Currently, Leafsnap’s catalog includes trees native to the northeast United States, but there are plans to expand it to make it more representative of the entire country. Quite brilliantly, the app will make good on the photographs users upload, sharing them and the trees’ location with the scientific community. From this, scientists will be able to further study the growth and decline of different tree species.

“Leafsnap was originally designed as a specialized aid for scientists and plant explorers to discover new species in poorly known habitats,” says Kress, in a press release. “Now Smithsonian research is available as an app for the public to get to know plant diversity in their own backyards, in parks and in natural areas. This tool is especially important for the environment, because learning about nature is the first step in conserving it.”