Research & Mapping
Casey Trees has been conducting research on D.C.’s trees through our Technical Services and Research Department since our founding. Using a combination of fieldwork, remote sensing and aerial imagery, Technical Services and Research draws from emerging techniques in urban forest management and on well-vetted methods of quantifying the benefits of urban trees. Technical Services and Research work consists of:
Tree Report CardThe 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 from various sources, including federal, state and private groups.
i-Tree Ecosystem Analysis 2015 (previously UFORE)
One of the many things that Casey Trees does well is monitor D.C.’s urban forest. We do this through a combination of activities including an assessment of 201 field plots located across D.C. every five years.
This quinquennial exercise is quite the undertaking.
First, the 201 field plots were selected using randomized gridding. What that means is that we put a grid over a map of D.C. and a computer chose about one plot for every 196 acres. Since the plots are randomly distributed, only a small number of them are on publicly accessible land. The vast majority of the plots are on privately owned land or have restricted access which requires us to seek out and secure permission to access the land.
Second, this exercise is very much a boots on the ground operation. While tree coverage is assessed using aerial imagery, this exercise requires the training up to 100 volunteers to travel to the 201 plots and properly collect and log the data.
Third, the collected data is run through a number of different models that look at the economic value of trees such as carbon storage and sequestration values. Those results are then incorporated into a paper detailing the current state of the District’s forest.
Trees & Income
This report addresses three questions:
1. How is tree canopy distributed across The District.
2. How changes in canopy from 2006 to 2011 are distributed.
3. Who, broadly, lives near the changes occurring in Washington, D.C.’s urban forest?
Since 2013 Casey Trees has studied the survival rates of our trees. We know the first three to four years are the most difficult for young trees in urban environments. Therefore, over the past three summers, a team of interns evaluated over 5,000 young trees by measuring different attributes including canopy condition, trunk diameter, planting location and survival status. Based on the sample, just over 80% of CT trees have survived since their planting date.