Fast Fact Library

Trees with small leaf size and high leaf complexity and trees with long "in leaf" periods like evergreens generally make the most effective barriers against roadside pollution and offer the most air quality benefits...

Barwise, Yendle, and Prashant Kumar. “Designing vegetation barriers for urban air pollution abatement: a practical review for appropriate plant species selection” npj Climate and Atmospheric Science 3, no. 12 (2020). https://doi.org/10.1038/s41612-020-0115-3.

Tree cover may improve academic performance. A study of 624 Illinois public high schools showed that tree cover density within a 1-mile radius of schools was positively associated with better ACT scores and college...

Li, Dongying, Yen-Cheng Chiang, Huiyan Sang, and William C. Sullivan. “Beyond the School Grounds: Links between Density of Tree Cover in School Surroundings and High School Academic Performance.” Urban Forestry & Urban Greening 38 (2019): 42–53. https://doi.org/10.1016/j.ufug.2018.11.001

A study of the 30 largest metropolitan areas in the United States found that walkable urban places (places developed for walkability and without prioritizing automobiles), perform better economically than sprawling...

Hadden Loh, Tracy, Christopher B. Leinberger, and Jordan Chafetz. Foot Traffic Ahead. New York: Smart Growth America and the George Washington University School of Business, 2019. https://smartgrowthamerica.org/resources/foot-traffic-ahead-2019/?download=yes&key=46188795

A study of 9,186 U.S. nursing homes found that increased tree canopy cover is associated with fewer depressive symptoms. This association did not vary by race or socioeconomic status of nursing home residents.

Browning, Matthew H.E.M., Kangjae Lee, and Kathleen L. Wolf. “Tree cover shows an inverse relationship with depressive symptoms in elderly residents living in U.S. nursing homes.” Urban Forestry & Urban Greening 41 (2019): 23-32. https://doi.org/10.1016/j.ufug.2019.03.002

At least 40% canopy coverage is needed to achieve the maximum cooling effect of trees in offsetting the urban heat island effect at the scale of a typical city block, according to this University of Wisconsin...

Ziter, Carly D., Eric J. Pedersen, Christopher J. Kucharik, and Monica G. Turner. “Scale-Dependent Interactions between Tree Canopy Cover and Impervious Surfaces Reduce Daytime Urban Heat during Summer.” Proceedings of the National Academy of Sciences 116, no. 15 (2019): 7575–80. https://doi.org/10.1073/pnas.1817561116

Areas of urban forest can contain as much carbon in above-ground biomass as similarly sized areas of tropical rainforest, according to a LiDAR analysis of trees in the London Borough of Camden.

Wilkes, Phil, Mathias Disney, Matheus Boni Vicari, Kim Caleders, and Andrew Burt. Estimating urban above ground biomass with multi-scale LiDAR. Carbon Balance Manage 13, 10 (2018). https://doi.org/10.1186/s13021-018-0098-0.

A visual preference survey of 836 Boston pedestrians and cyclists indicates a preference for trees and shrubs as dividers between bike lanes and traffic and the presence of trees alongside bike lanes over no trees...

Lusk, Anne C., Demostenes Ferreira da Silva Filho, and Lea Dobbert. (2018). Pedestrian and cyclist preferences for tree locations by sidewalks and cycle tracks and associated benefits: Worldwide implications from a study in Boston, MA. Cities. https://doi.org/10.1016/j.cities.2018.06.024

An in-depth analysis assessing urban tree cover and its impact on residential building energy use in the coterminous United States estimates a reduction of 38.8. million MWh or $4.7 billion in electricity use and...

Nowak, David J., Nathaniel Appleton, Alexis Ellis, and Eric Greenfield. (2017). Residential building energy conservation and avoided power plant emissions by urban and community trees in the United States. Urban Forestry & Urban Greening 21: 158-165. https://doi.org/10.1016/j.ufug.2016.12.004

A study of tree cover in and around the California residences of 7,910 participants suggests that increased tree cover in a neighborhood is related to better overall health, particularly lower rates of obesity and...

Ulmer, Jared M, Kathleen L. Wolf, Desiree R. Backman, Raymond L. Tretheway, Cynthia JA Blain, Jarlath PM O’Neil-Dunne, and Lawrence D. Frank. (November 2016). Multiple health benefits of urban tree canopy: The mounting evidence for a green prescription. Health & Place 42: 54-62. https://doi.org/10.1016/j.healthplace.2016.08.011

A global meta-analysis of 221 landscapes found that forest restoration enhanced biodiversity by 15-84% and vegetation structure by 36-77% as compared to degraded ecosystems. While restoration did not fully recover...

Crouzeilles, Renato, Michael Curran, Mariana S. Ferreira, David B. Lindenmayer, Carlos E. V. Grelle, and José M. Rey Benayas. A global meta-analysis on the ecological drivers of forest restoration success. Nature Communications 7, 11666 (2016). https://doi.org/10.1038/ncomms11666