Citizen Science

Join us at a park inventory

Citizen science is the collection and analysis of data relating to the natural world. At our park inventories, citizen science volunteers traverse the city collecting and documenting tree data that will be used to advance the field of urban forestry. No previous experience is required to become a citizen scientist, simply sign up for one of our upcoming park inventories. We’ll teach you everything you need to know on site.

Over the past year, we have inventoried thousands of trees across the district to determine the species, height, diameter of the trunk and health of the trees that are growing in our local and national parks. The information gathered at these events is mapped and analyzed to help manage our community forest and prioritize tree maintenance needs. We usually conduct our inventories when there are leaves on the trees — roughly May through October — that’s now! If you like getting outside and meeting people interested in the future of cities and the environment, sign up today.

Nominate a Park

Want Casey Trees to help measure a park in your neighborhood? Fill out this form to nominate a park or green space. We will get back to you in hopes of mobilizing and soon measuring.

Find a Tree

We use the data collected during inventories to create maps of D.C.’s trees. Use our maps to find the ones that shade your favorite parks and streets. Discover the locations of all the blossoming trees as well as those with the best fall foliage.

Tree Species Guide

We created a tree species guide for our park inventories! If you’ve ever seen a tree and wondered what it was, this waterproof guide with over 70 species found in the Washington metro area is for you. All proceeds go directly towards our Park Inventory program. Find it in our store.

i-Tree Ecosystem Analysis

Our i-Tree Ecosystem Analysis report uses the data collected by citizen scientists to tracks the benefits of trees over time. If you’re curious about the numerical value of D.C.’s trees when it comes to storm water management, air pollution and carbon storage, read this report.

i-Tree Ecosystem Analysis 2015 | i-Tree Ecosystem Analysis 2010 | i-Tree Ecosystem Analysis 2006

Tree Report Cards

Casey Trees’ Tree Report Card measures the quantity and condition of D.C.’s trees and the collective efforts of all groups and individuals working to achieve the District’s 40 percent tree canopy goal. It is based on data collected from both public and private sources, including the District and Federal Governments, universities, developers, nonprofits, citizen scientists and others.

2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008


Full Calendar

Tree Report Card 2018


i-Tree Ecosystem Analysis


D.C. Tree Inventory Map