Leafsnap: An Electronic Field Guide

Columbia University, the University of Maryland, and the Smithsonian Institution are working on visual recognition software to help identify species from photographs. Leafsnap is 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, fruits, petioles, seeds, and bark. The high-resolution images in the original app were created by the conservation organization Finding Species.

The Original Leafsnap currently includes the trees of the Northeast United States and will soon grow to cover the trees of the entire continental United States.

Leafsnap UK includes trees from across the United Kingdom with species information and imagery provided by the Natural History Museum in London

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.

The Leafsnap family of electronic field guides aims to leverage digital applications and mobile devices to build an ever-greater awareness of and appreciation for biodiversity. Click on "Species" above to browse Leafsnap’s gallery of species. (Leafsnap UK species are not included here.)

The genesis of Leafsnap was the realization that many techniques used for face recognition developed by Professor Peter Belhumeur and Professor David Jacobs, of the Computer Science departments of Columbia University and the University of Maryland, respectively, could be applied to automatic species identification.

Professors Jacobs and Belhumeur approached Dr. John Kress, Chief Botanist at the Smithsonian, to start a collaborative effort for designing and building such a system for plant species. Columbia University and the University of Maryland designed and implemented the visual recognition system used for automatic identification. In addition, Columbia University designed and wrote the iPhone, iPad, and Android apps, the leafsnap.com website, and wrote the code that powers the recognition servers. The Smithsonian was instrumental in collecting the datasets of leaf species and supervising the curation efforts throughout the course of the project. As part of this effort, the Smithsonian contracted the not-for-profit nature photography group Finding Species, which collected and photographed the high-quality photos available in the apps and the website. UK species were also collected and photographed by the Natural History Museum, London, UK.

For press inquiries, please email press@leafsnap.com.

Frequently Asked Questions


How do I create an account?
The first time you take a photo, it automatically creates an account for you, after which you can go to the options screen and change your username and/or password.
How do I label a potential match as the correct species?
Simply "swipe" across the result to mark it as that species.
How do I delete an image from my collection?
Simply "swipe" across the image on the collection page to delete it.
Why was my leaf not recognized?
Photos of leaves must be taken with a single leaf on a fully-white background for our automatic algorithms to find them. Also, keep in mind that the app must first send the image to our servers for processing, and so you must have a working internet connection when you press "Snap It!" No internet connection is required to browse through the rest of the field guide, however.
When will there be an Android version of Leafsnap?
We have one under development, but since the app is free and the work is being done by volunteers, we do not have a release date, nor a firm guess as to when this will be.
Will there be a Blackberry/Palm/Windows Mobile/Windows/Computer version of Leafsnap?
We are working on a volunteer basis and thus have to prioritize our efforts. Our primary goals are to expand coverage and release an Android app first. After that, we will consider additional platforms if there is sufficient demand.
When will you have coverage of my city/region/country?
We are working to first complete coverage of the Northeast US, then the rest of the United States, and finally the rest of the world.
I am a botanist, ecologist, arborist, or tree expert, and would like to volunteer in future collection efforts. How can I do this?
Please email us at volunteer@leafsnap.com - we are keeping a list of those experts that have offered to volunteer, with the hope of building such a collaborative mechanism in the near future.
I am not an expert on trees but would like to help in collecting photographs. How can I do this?
Please email us at volunteer@leafsnap.com - we are keeping a list of potential volunteers that could help with collecting field photographs.

Columbia University


Peter Belhumeur supervises the Columbia team.

Neeraj Kumar is leading the software development effort.

Jacky Jacob helped develop the iPhone app.

Sean White lead the design and development of early tablet PC, UMPC, and mobile phone prototypes and helped with the initial design of the current iPhone app.

Weikang Wan is building an automated tool for data curation.

Priyank Singh worked on improving the leaf identification algorithms.

Peiti Li is developing the website.

Oliver Sui is developing the Android app.

Aman Agrawal improved the performance of the feature extraction code.

Yu Huang is working on testing the website and API.

Ila Agrawal helped with leaf identification.

Qi Liang helped work on the website design.

Wenxin Zhu is developing the Android app.

Paul Vishayanuroj is developing the iPhone app.

Yu-Wei Chang is developing the iPad app.

Vinay Kumar stress-tested the backend and worked on database management.

Jian Ma originally created the website and is working on its design.

Wei Li designed the Leaflet game and has worked on automating our image editing pipeline.

Yi Zhang is developing the Android app.

Chun-Kang Chen is automating the backend processing pipeline.

Steve Feiner is helping supervise the design of the user interfaces.

Wei An is developing the website.

Guangyu Sun is investigating new leaf identification algorithms.

Ivy Deliz started the iPad app, helped develop the iPhone app, and lent a hand in the design of the Leaflet game.

Joseph Lin helped develop the iPhone app and was one of the original Central Park Collectors.

Vincent Zeng worked on profiling and porting the segmentation and recognition code to the iPhone.

Gaurav Agrawal explored the use of SIFT for leaf recognition.

Emma Liu is developing the iPad app.

Yin Liu is developing the website.

University of Maryland


Daozheng Chen has worked on speeding up the recognition code.

David Jacobs supervises the University of Maryland team.

Arijit Biswas is working on improving the leaf identification algorithms.

Joao Soares is working on image segmentation for leaves.

Haibin Ling designed the original leaf recognition algorithm and participated in the development of the initial electronic field guide (EFG) prototype.

Angjoo Kanazawa is working on improving the leaf recognition algorithm.

Aditya Malik is working on image segmentation for leaves.

Smithsonian Institution


Jamie Whitacre is the Smithsonian database developer for the project.

Ida C. Lopez is the project coordinator at Smithsonian. She also led the collection expedition into the wilds of Central Park in New York City.

Ingrid Pol-Yin Lin is the Smithsonian photographer who images voucher specimens and leaves used in the project.

Rusty Russell, US Herbarium Manager, is the Smithsonian co-investigator for the project.

W. John Kress, PhD. is the Principal Investigator of the Leaf Project at the Smithsonian.

Norm Bourg, PhD., was the plant specimen collector for much of the project.

Ellen Farr is the Smithsonian Botany Department computer specialist.

Daniel Grant is a long-term volunteer in the Smithsonian Botany Department. He assists with specimen and image data processing.

James Short is a long-term volunteer in the Smithsonian Botany Department. He assists with specimen and image data processing.

Finding Species


Michael Honsaker has provided technology support and maintained photographic metadata.

Michelle Downey collects plants in the Southeastern US and processes photographs.

Yuri Huta created Finding Species'' photographic method for the high-resolution photographs in LeafSnap, and has photographed plants.

Diego Acosta assists with processing and editing photographs, and photographs plants on special expeditions.

Tanya Tarasova has researched flowering times, coordinated expeditions, and assisted with permits. She has provided administrative oversight.

Margot S. Bass coordinates the Finding Species LeafSnap US team, and conceived of the standardized high-resolution plant photographs.

Gorky F. Villa Muñoz is the current lead botanist for LeafSnap from Finding Species, collecting and photographing plants throughout the US.

Matthew Smith has collected plants in the DC area.

Leonel Velasquez trains the Finding Species botanical photographers. He photographs plants for LeafSnap on special expeditions.

Roxana Bravo has refined details in the high-resolution photographic method, and has photographed plants.

Linda Keenan writes the Plant Profiles and has collected plants in the DC and Boston areas.

Hugo Mogollon supervises the Finding Species team, in the US and South America.

Martin Bustamante coordinates the Finding Species photographers and solves photographic challenges.

Bejat McCracken is the current lead US photographer for LeafSnap from Finding Species and selects high-resolution photographs.

Special Acknowledgements


The Leafsnap team extends many thanks to the gardens, parks and arboreta which gave us the opportunities to photograph and gather data for the Leafsnap app.
  • Adkins Arboretum, Ridgely, MD
  • The Arnold Arboretum of Harvard University, Boston, MA
  • Brookside Gardens, Wheaton, MD
  • Central Park Conservancy, New York City, NY
  • The City of Takoma Park, MD
  • The City of New York, NY
  • Chesapeake and Ohio Canal National Historic Park, National Park Service, DC, MD and WV
  • George Washington National Forest, U.S. Forest Service, Millboro, VA
  • Houston Arboretum and Nature Center, Houston, TX
  • Mercer Arboretum & Botanic Garden, Humble, TX
  • Montgomery County Department of Parks, Silver Spring, MD
  • Smithsonian National Zoological Park, Washington, DC
  • Old City Cemetery, Lynchburg, VA
  • Rock Creek Park, National Park Service, DC
  • San Antonio Botanical Gardens, San Antonio, TX
  • The Scott Arboretum of Swarthmore College, Swarthmore, PA
  • The State Arboretum of Virginia (Orland E. White Arboretum) and Blandy Experimental Farm, Boyce VA
  • Stephen F. Austin Mast Arboretum at Stephen F. Austin University, Nacogdoches, TX
  • Smithsonian Conservation Biology Institute, Front Royal, VA
  • United States National Arboretum, Washington, DC
Our sincere appreciation to the following individuals who have facilitated use of their garden, park or arboretum collections and supported the team in gathering data for Leafsnap.
Ellie Altman, Edward Sibley Barnard, Jane and George Bass, Scott Bell, Carole Bergmann, Todd Bolton, Norman Bourg, Ph.D., Matthew Brown, Andrew Bunting, Neil Calvanese, David Carr, Nancy Cowden, PhD., Charlie Davis, Ted Delaney, Michael S. Dosmann, Ph.D., Geoffrey Fenner, Doug Gill, Ph.D., Sarah Hill, Jack Kyte, Richard Lieberman, Cheryl A. Lindeman, Ed.D., Rhoda Maurer, Shawn McCracken, PhD, Phil Normandy, Janice Owens, Kathryn Reshetiloff, Kathryn Richardson, T'ai Roulston, and Kevin Tunison.