Come one, come all—especially if you’re fond of trees. The NYC Parks Department has officially launched the 2025 tree census, continuing a decennial tradition that started in 1995, and are seeking volunteers.
Trees, as the Parks Department points out, provide an array of benefits: carbon sequestration, air-quality improvement, stormwater management, and urban heat-island reduction.
The census will last two years, and will measure the size, condition, and location of the city’s trees. Collected data will reportedly go toward planting trees in areas that lack them. It will be conducted with the assistance of a mobile app, ArcGIS Field Map, which volunteers can download and use to update tree info.
Volunteers are supposed to sign up for a designated census event, although they can then set out for individual tree-counting afterward, as well as track their progress and meet census goals.
Two separate tree counts are being conducted in Manhattan until Aug. 1, one in Jackie Robinson Park in Harlem and one in Morningside Park, although more training sessions will certainly be added to the calendar. Readers interested in volunteering can sign up at www.nycgovparks.org/reg/trees-count.
Sessions will begin with training on how to properly identify trees, as well as assess their health. Teams will then split up for a one-to-two-hour count. As an explainer video released by the Parks Department puts it, “The easiest way to identify a tree is by its leaves.” After all, leaves have different edges, and are arrayed around branches in different ways. Volunteers will also be checking for telltale bark patterns, seeds, flowers, or fruits.
Volunteers will also be assessing and uploading other relevant metrics, such as how many trunks a tree has. Finally, they’ll be taking measurements of the trees’ circumference, which can be done with a good old-fashioned analog tape measure.
In fact, the most handy resource for understanding the volunteer process may be found at the “TreeCount2025 HUB” website, which has a downloadable data-collection guide.
“Trees Count 2025 represents an incredible opportunity that comes only once a decade—the chance for New Yorkers to directly engage with the forest within our city and to help shape its future,” Parks Commissioner Iris Rodriguez-Rosa said in a statement. “This isn’t just about collecting data—it’s about building the next generation of environmental stewards who understand the critical role our tree canopy plays in creating healthier, more resilient communities.”
The last tree census, in 2015, drew together more than 2,200 volunteers—and mapped 666,134 street trees. That census calculated that NYC derives a total of $151.2 million in “annual benefits” from its trees.
The 2005 tree census focused on quantifying ecological benefits, according to the Parks Department, and provided a foundation for the OneMillionTrees initiative that launched in 2007. That project, which unsurprisingly focused on planting 1 million trees in NYC, reached its milestone in 2015.
This year’s census will reportedly create a 40-year longitudinal dataset on NYC’s trees, allowing the Parks Department to conduct extensive policy planning on tree allocation and tree health well into the future.
“Trees Count 2025 represents . . . the chance for New Yorkers to directly engage with the forest within our city and to help shape its future” — Parks Commissioner Iris Rodriguez-Rosa