Fast Fact Library

In a Berlin study, home window views that afforded a higher percentage of vegetation as well as a higher diversity of plant material were connected to lower stress levels in residents, as indicated by lower hair...

Honold, Jasmin, Tobia Lakes, Reinhard Beyer, and Elke van der Meer. “Restoration in urban spaces: Nature views from home, greenways, and public parks.” Environment and Behavior, 48.6 (2016): 796-825.

Tree species differ in their ability to reduce air and surface temperatures and increase relative humidity. Trees with a high leaf-area density and rate of transpiration are more effective at cooling air...

Gillner, Sten, Juliane Vogt, Andreas Tharang, Sebastian Dettmann, and Andreas Roloff. (2015). Role of street trees in mitigating effects of heat and drought at highly sealed urban sites. Landscape and Urban Planning, 143, 33-42.

In this study of New York City streetscapes, trees made people feel safer than building-related variables, and tall, narrow streetscapes made people feel safer than short, wide streetscapes. More buildings per...

Harvey, Chester, Lisa Aultman-Hall, Stephanie E. Hurley, and Austin Troy. (2015). Effects of skeletal streetscape design on perceived safety. Landscape and Urban Planning, 142, 18-28.

A study in Toronto, Canada found that having 10 more street trees on a city block, on average, improves health perception in ways comparable to an increase in annual personal income of $10,000 and moving to a...

Kardan, Omid, Peter Gozdyra, Bratislav Misic, Faisal Moola, Lyle J. Palmer, Tomáš Paus, and Marc G. Berman. (2015). Neighborhood greenspace and health in a large urban center. Scientific Reports, 5.

Trees in bioswales reduce runoff and discharge and return stored water to the atmosphere. Transpiration from trees in bioswales at The Morton Arboretum parking lot in Illinois accounted for 46-72% of the lot’s total...

Scharenbroch, Bryant C., Justin Morgenroth, and Brian Maule. (2015). Tree Species Suitability to Bioswales and Impact on the Urban Water Budget. Journal of Environmental Quality.

Increasing the number of native mature trees preserved in new urban housing developments is an effective way to increase bird diversity, according to this study in Queensland, Australia. Streets that retained mature...

Barth, Benjamin James, Sean Ian FitzGibbon, and Robbie Stuart Wilson. (2015). New urban developments that retain more remnant trees have greater bird diversity. Landscape and Urban Planning, 136, 122-129.

Urban middle school students in Canada were more physically active when their neighborhoods contained undeveloped natural areas with trees but not meadows. For every 5% increase in tree-covered land, there was a...

Janssen, Ian, and Andrei Rosu. (2015). Undeveloped green space and free-time physical activity in 11 to 13-year-old children. International Journal of Behavioral Nutrition and Physical Activity, 12(1), 26.

According to a 2013 study of lawns in the Los Angeles metropolitan area, low-density plantings of trees on irrigated lawns can significantly reduce turfgrass evapotranspiration through partial shading and serve as a...

Litvak, Elizaveta, Neeta S. Bijoor, and Diane E. Pataki. (November 2013). Adding trees to irrigated turfgrass lawns may be a water-saving measure in semi-arid environments. Ecohydrology 7(5): 1314-1330. https://doi.org/10.1002/eco.1458

Data collected from 1990 to 2007 suggests that loss of trees to the emerald ash borer increased human mortality related to cardiovascular and lower-respiratory-tract illness. Across the 15 states in the study area...

Donovan, Geoffrey H., David T. Butry, Yvonne L. Michael, Jeffrey P. Prestemon, Andrew M. Liebhold, Demetrios Gatziolis, and Megan Y. Mao. (2013). The relationship between trees and human health: Evidence from the spread of the Emerald Ash Borer. American Journal of Public Health 44(2), 139-145.

A study of single-family homes in Portland, Oregon found that trees in the public right of way are associated with lower crime rates. The effect of trees on a house's lot was mixed. Lot trees small enough to block...

Donovan, Geoffrey H., and Jeffrey P. Prestemon. (2012). The effect of trees on crime in Portland, Oregon. Environment and Behavior, 44(1), 3-30.