Equitable Distribution of Tree Cover in the USA Northeast Megalopolis

Abstract

Urban green spaces are critical components of sustainable cities, consisting of vegetation spanning across different land uses such as parks, residential lots, and streets. Trees are a large component of urban green space and serve a variety of functions which are largely determined by the land use on which a tree lives. For example, park trees provide an opportunity to escape city life, connect with nature, and engage in recreational activities; residential trees provide shade and reduce energy consumption; and trees lining streets improve neighborhood walkability by providing safety from oncoming traffic. In an attempt to better capture these benefits, cities are increasingly implementing urban tree cover goals. However, the disadvantaged neighborhoods that already have disproportionately low tree cover, do not always benefit from these city-wide tree cover goals. Focusing on the major United States cities that make up the Northeast Megalopolis region of Washington D.C., Baltimore, Philadelphia, New York, and Boston, we develop and use high-resolution tree cover data to measure which socioeconomic and racial/ethnic groups are more likely to live in areas that have achieved a city’s tree cover goal. We also break down our high-resolution tree cover data by land use into three categories: residential trees, park trees, and street trees. The accessibility of these three types of tree cover is assessed at the census tract level to identify any inequities in tree coverage. Results can be used to identify which neighborhoods should be targeted for tree plantings to achieve demographically equitable tree coverage goals.