Name: Leafsnap
Platform: iOS
Cost: Free

Leafsnap has languished for years on my phone. The app represents the sort of big audacious online project that we as librarians need to know about. Merging geographic location with image recognition, it combines reports from the field to produce an interactive electronic guide.

For the end user, Leafsnap is designed to make a “best guess” about the species of a plant, based on an image of a leaf you upload or input through the camera. I hadn’t been able to use it before last week. It’s limitation? Spearheaded by the Columbia University, the University of Maryland, and the Smithsonian Institution, Leafsnap is crowd-sourced, and a caveat warns that the database best reflects the northeasten U.S. for the time being (though there is a U.K. version, too). When I heard someone speculating about the name of a specific tree while I was in Massachusetts, I was happy to put the tool to work.

One word on technique: I had better success when I photographed and cropped around a leaf beforehand, and you will need a “true white” background — the reverse side of an index card works fine. The app converts your image into an “x ray” of the leaf, queries the database and returns with a series of options, all of which contain Leafsnaps as well as more holistic images of matching plants.

Using the apps involves creating an account in Leafsnap’s user-driven botanical database to track your scanning and positive identifications. Inside the app, you’re creating your own log book, marking each species with a swipe, with a geographic distribution as well.

The process of collecting and marking specimens can be addictive; even your most tender-hearted teen will respect the do-no-harm approach to nature the app represents. Within the database, the specimens link to the Encyclopedia of Life, another ambitious, crowd-sourced online project, and there’s an integrated program designed to improve your recognition skills.

It only occurred to me after the fact that leafsnap enables a twenty-first century manifestation of the very nineteenth century impulse for classification among amateur botanists. For contrast, you can see a digitized version of Emily Dickinson’s old school herbarium here.

Leafsnap offers a fun, mobile way to involve the natural world in your summer STEM programming. And while the geographic scope of the database might seem to limit its utility, I’ve found that it works just fine beyond the specified region.

Have a suggestion for App of the Week? Let us know. And find more great Apps in the YALSA Blog’s App of the Week Archive.