"If you've ever wondered what type of tree was nearby but didn't have a guide book, a new smartphone app allows users with no formal training to satisfy their curiosity and contribute to science at the same time.

Scientists have developed the first mobile app to identify plants by simply photographing a leaf. The free iPhone and iPad app, called Leafsnap, instantly searches a growing library of leaf images amassed by the Smithsonian Institution. In seconds, it returns a likely species name, high-resolution photographs and information on the tree's flowers, fruit, seeds and bark.

Users make the final identification and share their findings with the app's growing database to help map the population of trees one mobile phone at a time.

Leafsnap debuted in May, covering all the trees in New York's Central park and Washington's Rock Creek Park. It has been downloaded more than 150,000 times in the first month, and its creators expect it to continue to grow as it expands to Android phones."

Brett Zongker reports for the Associated Press June 8, 2011. [2]