Tree Research

To help local tree advocates make the case for trees in their communities, ACTrees has compiled Benefits of Trees and Urban Forests: A Research List.  This research listing includes over 150 tree benefits and facts, ranging from the national to the hyper-local level, and all with complete scientific citations. This information tells the story of trees in dollars and cents, in pounds and percents, with compelling data about why maintaining and growing a healthy urban forest is a smart, sustainable investment. Learn more.

And check out other current research that may be of interest to those in the urban greening community. For a full list of research, visit the Research Archive.

Reforestation Near Metro Areas May Offer Cost-Effective Ozone Reduction

Arlington, VA (September 8, 2014) — A new study suggests that large-scale peri-urban forest restoration, or replanting trees around an urban periphery, can help reduce air pollution abatement and compliance costs, while at the same time providing benefits to nature and people that conventional, technological pollution controls do not deliver.

Portland’s Trees Provide $6.6M Annually in Reduced Air Pollution Benefits

Portland, OR (August 26, 2014) — A new Portland State University study that maps Portland’s air pollution patterns highlights the air-cleansing benefit of urban trees. According to the research, published in Environmental Pollution, Portland’s urban canopy keeps kids in school, thwarts asthma attacks, curbs emergency room visits and helps elderly residents stay out of the hospital.

University of Washington Research Shows Value of Community Engagement

By Wolf, K.L., S. Kreuger, and K. Flora.

Seattle, WA (2014) — A new University of Washington literature review finds that place attachment and meaning are particularly relevant when considering issues of urban development and community-building. Attachment and meaning emerge from a variety of experiences and situations, and are often related to parks, green spaces, and natural areas. This connection may serve to promote and encourage environmentally responsible behavior using appeals to individuals’ self-identity and dependence.

Trees and Forests Improve Air Quality and Human Health

By Nowak, David J.; Hirabayashi, Satoshi; Bodine, Allison; Greenfield, Eric

Syracuse, NY (July 25, 2014) — In the first broad-scale estimate of air pollution removal by trees nationwide, U.S. Forest Service scientists and collaborators calculated that trees are saving more than 850 human lives a year and preventing 670,000 incidences of acute respiratory symptoms.

Urban Heat Boosts Some Pest Populations 200-Fold

By Adam G. Dale and Steven D. Frank, North Carolina State University

Raleigh, NC (July 23, 2014) — New research from North Carolina State University shows that urban “heat islands” are slowly killing red maples in the southeastern United States. One factor is that researchers have found warmer temperatures increase the number of young produced by the gloomy scale insect–a significant tree pest–by 300 percent, which in turn leads to 200 times more adult gloomy scales on urban trees.

Environmental Justice: The Challenge of Making Cities ‘Just Green Enough’

By Jennifer R. Wolch, Jason Bryne, Joshua P. Newell

Berkeley, CA (March 2, 2014) — From green roofs in Chicago to the High Line in Manhattan, U.S. cities have been making high-profile investments in green space. But could there be a downside to urban greening? A growing body of academic literature examines a paradox: Low-income communities tend to suffer from various kinds of environmental injustice, including shortage of green space. But when these concerns are addressed–the power plant closes, a park opens–the neighborhood becomes more desirable, often kickstarting a process of “environmental gentrification.”

“Green Altruism”: Short Immersion in Natural Green Environments and Helping Behavior

By Nicolas Guéguen and Jordy Stefan

France (July 1, 2014) — New research from France finds strangers are more helpful if they’ve just strolled through a natural environment. Research has consistently found exposure to a natural environment to be associated with health and psychological well-being. However, the effect of such an environment on social behavior and relationships remains in question.

Strong Contributions of Local Background Climate to Urban Heat Islands

By Lei Zhao, Xuhui Lee, Ronald B. Smith & Keith Oleson

July 9, 2014 — Recent research published in the journal Nature, looks at the affect of background climate on urban heat islands (UHI). The UHI, a common phenomenon in which surface temperatures are higher in urban areas than in surrounding rural areas, represents one of the most significant human-induced changes to Earth’s surface climate.

Grey to Green: Creating “Cool” Cities Symposium Wrap-Up

Dallas, TX (July 21, 2014) — The cities where we live are heating up, but trees and green infrastructure can help them stay cool. In late May, the Texas Trees Foundation hosted a regional conference, Grey to Green: Creating “Cool” Cities. They’ve just released a wrap-up report from the symposium which featured keynote speaker Dr. Brian Stone, an expert on urban environmental planning at the Georgia Tech.

Release of Fading Forests III Report

Arlington, VA, and Knoxville, TN (May 23, 2014) — A new report released by the University of Tennessee Institute of Agriculture and The Nature Conservancy compiles the latest data and analyses on the introduction, spread, and costs of non-native invasive tree pests and diseases. Fading Forests III is the third study on invasive forest pests produced by the authors over a 20-year period.