Sunday, March 21 commemorated the ninth annual International Day of Forests. The value of “the woods” has been fully evident during this past year, as people have struggled to find relief in challenging times. Whether at a National Forest, in a local park, or on a neighborhood walk, trees and forests have provided comfort, a place to connect to others, and a space to breathe. Many of us have opened our eyes to how integral trees and forests are to the American landscape. But with this awareness has come the recognition of huge disparities in access to these spaces by low-income and majority-minority communities.
Our cities have long recognized the importance of trees in their infrastructure, which has led to the emergence of Tree City USA, a program supported by the Arbor Day Foundation that celebrates and nurtures the residential tree canopy. Currently, over 3,400 municipalities across the nation have met the program’s standards to become Tree Cities by achieving 40 percent canopy cover. For instance, Baltimore, Maryland, recently celebrated the planting of its 10,000th tree in October 2020 and has explicitly recognized the importance of providing green infrastructure in less wealthy neighborhoods.
City managers have recognized the need to invest in green infrastructure. Clear evidence demonstrates the health benefits of trees: research has shown that hospital patients recover more quickly when they see trees, gardens, and nature through hospital windows. And positive environmental outcomes sprout from forests: 100 healthy trees can capture 200,000 gallons of water, reducing stormwater runoff and lowering the cost of managing that water. Trees absorb air pollutants, improving ambient air quality. The increased interest in nature-based solutions to climate change has put a spotlight on the carbon sequestration potential of trees and helped lead to the Trillion Trees campaign, which promotes reforestation.
Urban spaces can contribute to achieving these goals, as studies show that urban trees store over 708 million tons of carbon and capture an additional 28.2 million tons of carbon per year in the United States (approximately 0.05 percent of U.S. annual emissions). The i-Tree calculator has been developed by the US Department of Agriculture Forest Service to better quantify these values and better inform city managers about the potential benefits of urban forests (Figure 1).
