Mobile App Helps Map Philly’s Trees

Street trees play a crucial role in creating a healthy urban environment by improving air quality, reducing energy costs for homeowners, and even enhancing property values. Since April 2011, people in the greater Philadelphia area have been showing their love for trees by adding information to PhillyTreeMap, a web application that encourages the public to get involved in the process of mapping the urban forest.

Almost immediately after the site’s launch, Azavea, the geospatial software design firm that built PhillyTreeMap, began receiving questions about when a mobile app version would be available. After all, if you’re going to map a tree, wouldn’t it be much easier to add details about that tree while standing directly in front of it? Funded by a second phase grant from the USDA National Institute of Food and Agriculture Small Business Innovation Research Program (Grant Number 2011-33610-30862), Azavea partnered with several organizations including the Pennsylvania Horticultural Society, Philadelphia Parks & Recreation, and Urban Ecos to create a mobile version of OpenTreeMap (the software that powers PhillyTreeMap). The goal was to build an app that would enable users to explore, add, and edit tree information directly from their iPhone or Android devices.

After much development, the first mobile version of OpenTreeMap became available in August 2012 when the PhillyTreeMap mobile app was released for use on iPhones and iPads. After downloading the app, PhillyTreeMap users can view nearby trees or find trees by species, diameter, and other characteristics. Users can create a free account in order to add new trees or edit existing tree information. All data added via the iPhone app is sent to the PhillyTreeMap database and is visible on the website. An Android version of the app should be available later this fall.

Even before the release of the PhillyTreeMap app, one tree survey project was already exploring the idea of inventorying trees using mobile technology. Interns at the Delaware Valley Regional Planning Commission accessed PhillyTreeMap via iPads to survey over 1,500 trees in the South Philadelphia and Whitman neighborhoods. Since PhillyTreeMap is optimized for use on a tablet computer, the interns could edit existing tree data and add new trees directly in PhillyTreeMap and then export their survey results for further spatial analysis. The project also served as an opportunity to test the use of iPads for a tree survey. The interns provided some great suggestions on how to improve the design of PhillyTreeMap, and their experiences showed that the iPads could be used for a few hours of surveying at a time without the tablets overheating, draining the batteries, or using too much of the data plan.   

Philadelphia is not the only city exploring the use of mobile technology for inventorying trees. The OpenTreeMap software that powers PhillyTreeMap is also in use in San Francisco, Sacramento, San Diego, and Grand Rapids, Michigan. Both the San Francisco and Sacramento tree maps recently launched their own iPhone apps. Those apps are currently being used by citizens involved in the Great Tree Count, a week long effort to map trees in both cities.

The OpenTreeMap project is an open source effort, and the code for the mobile version is available for free at www.opentreemap.org. Organizations interested in exploring web-based technology for urban forestry are welcome to download the code to build a similar project for their community. Azavea and its partners plan to continue to add new features to the OpenTreeMap software over the next year.