Trees are essential to healthy communities.
Trees in the built environment provide such a wide array of services to the community.
Read on for all the ways trees play a part in healthy, vibrant communities.
Read on for all the ways trees play a part in healthy, vibrant communities.
Removing Pollution from the AirTrees can remove up to 60% of street-level air pollution, including carbon dioxide, ozone, nitrogen dioxide, sulfuric dioxide (a component of smog), and particulate matter (i.e., dust, ash, dirt, pollen, and smoke) (Coder 1996). This service has a very significant impact on public health. Alleviation of Heat StressUrban trees are widely accepted as one of the most effective long-term solutions to reducing the effects of urban heat islands, and can lower ambient temperatures by 20–45°F (EPA 2015). Why is this even important? Heat stress has been proven to cause significant public health problems and even mortality. Each year, more Americans die from extreme heat than all other natural disasters combined (i.e., hurricanes, floods, tornadoes, lightning). Crime Rate ReductionsA study in Baltimore found that a 10% increase in tree canopy was associated with a roughly 12% decrease in crime. It has also been shown that outdoor areas populated with trees tend to suffer from less graffiti, vandalism, and littering than their treeless neighbors (PHS 2015). Sustaining Wildlife HabitatTrees are an essential component to habitat and conservation in urban areas. They intercept and clean large quantities of polluted stormwater, preventing further degradation to vital aquatic and terrestrial habitats. Additionally, as smaller forests are connected through planned or informal urban greenways, trees provide essential habitat to a range of birds, pollinators, and other wildlife that feed on insects (Dolan 2015). A healthy wildlife population indicates a healthy place for people to live too. Higher Property ValuesTrees have been shown to increase residential property and commercial rental values by an average of 7% (Wolf 2007). |
Public Health Improvements- Both Mental and Physical - Trees have been shown to create healthy environments for people by improving air quality and reducing heat island effects. New York City saw a significant decrease of asthma in young children (-29%) after increasing its tree canopy through the installation of over 300 trees for each square kilometer (Lovasi et al. 2008). Studies have also shown that individuals with views or access to greenspace tend to be healthier; employees experience 23% less sick time and greater job satisfaction, and hospital patients recover faster with fewer drugs (Ulrich 1984). Stronger CommunityTree-lined streets can create stronger communities and attract new residents. While less quantifiable, the tree benefits related to community building are no less important than other services. One study showed that residents of apartment buildings surrounded by trees reported knowing their neighbors better, socializing with them more often, having stronger community, and feeling safer and better adjusted than did residents of more barren, but otherwise identical areas (Kuo and Sullivan 2001). Noise & Pollution ReductionPollution and noise from busy roadways and rail lines can create unhealthy and undesirable conditions for those living nearby (ALA 2015). Buffers of trees reduce both noise and pollution. A 100-foot-wide, 45-foot-high densely-planted tree buffer can reduce highway noise by 50% (NC State 2012). Better Test ScoresIt's been found that the more tree cover around a school, the better test scores will be. Why? The increased exposure to nature that trees provide helps to increase concentration and engagement, while also leading to less disruptive behavior (Kuo et. all 2020). Higher CreativityAfter 3 days of forest therapy, participants found not only positive physiological responses such as reduced heart rates and blood pressure, but also an increase in positive emotions, decrease in negative emotions (like bewilderment and confusion), and a 28% increase in creativity (Yu & Hsieh 2020). |
More Successful Business DistrictsStudies have shown that tree-covered commercial shopping districts are more successful than those without canopy. In multiple studies, consumers showed a willingness to pay 12% more for goods and shopped for a longer period of time in shaded and landscaped business districts (Wolf 1999, 2003, 2005). Consumers also felt that the quality of products was better in business districts surrounded by trees and were willing to pay more (Wolf 1998). Safer, More Walkable StreetsWalkability and pedestrian-friendly areas tend to draw the most people; also, tree cover is a powerful tool in revitalizing districts and neighborhoods. Urban trees have been shown to slow traffic and help ensure safe, walkable streets. Traffic speeds and driver stress levels have been reported to be lower on tree-lined streets, contributing to a reduction in road rage and aggressive driving (Wolf 1998a, Kuo and Sullivan 2001). According to the Federal Highway Administration, tree canopy along a street discourages speeding (U.S. Department of Transportation 2015). The buffers between walking areas and driving lanes created by trees make streets feel safer. Water Pollution ReductionAs cities grow, the amount of land that naturally absorbs rainwater (i.e., lawns, parks, fields, woods) tends to shrink, while hard surfaces that cause rain to runoff (i.e., roads, buildings, parking lots) increase in area. After flowing over roads, parking lots, and lawns, rainwater accumulates fertilizers, oil, chemicals, grass clippings, litter, pet waste, and other contaminants, polluting water. One mature deciduous tree can intercept over 500 gallons of rainwater a year, while a tree that holds leaves all year (e.g., pine, magnolia) can intercept up to 4,000 gallons per year (Seitz 2008). Energy SavingsTrees reduce cooling and heating costs, both through their shade as well as emissions of moisture. In fact, the cooling effect of one healthy tree is equivalent to 10 room-sized air conditioners operating 20 hours a day (North Carolina State University 2012). The shade of properly-placed trees can save homeowners up to 58% on daytime air conditioning costs, while mobile homeowners can save up to 65% (Smith 1999). Better SleepHigher rates of urban tree canopy was associated with a higher quantity of quality, deep sleep in middle to older-aged adults (Astrell-Burt & Feng 2019). |
REFERENCES:
American Lung Association (ALA). 2015. State of the Air 2015. http://www.stateoftheair.org (accessed May 30, 2015).
Astrell-Burt, T., Feng, X. 2019. Does sleep grow on trees? A longitudinal study to investigate potential prevention of insufficient sleep with different types of urban green space. SSM - Population Health https://www.sciencedirect.com/science/article/pii/S2352827319301703
Coder, R.D. 1996. “Identified Benefits of Community Trees and Forests.” University of Georgia Cooperative Extension Service, Forest Resources Publication FOR96-39.
Dolan, RW. 2015. "Two Hundred Year of Forest Change: Effects of Urbanization on Tree Species Composition and Structure." ISA Aboriculture & Urban Forestry. 41 (3): 136-145
EPA U.S. Environmental Protection Agency. 2015. Heat Island Effect: Trees and Vegetation. http://www.epa.gov/heatislands/mitigation/trees.htm. Accessed May 30, 2015.
Kuo, F., and W. Sullivan. 2001. “Aggression and Violence in the Inner City: Effects of Environment via Mental Fatigue.” Environment and Behavior 33(4):543–571.
Kuo, M., Klein, S., Browning, M., Zaplatosch, J. 2021. "Greening for Academic Achievement: Prioritizing What to Plant and Where." Landscape and Urban Planning 206:103962.
Lovasi, G.S., Quinn, J.W., Neckerman, K.M., Perzanowski, M.S., & Rundle, A. 2008. “Children Living in Areas with More Street Trees have Lower Prevalence of Asthma.” Journal of Epidemiology & Community Health. 62:7(647-49).
North Carolina State University. 2012. “Americans are Planting Trees of Strength.” http://www.treesofstrength.org/benefits.htm. Accessed May 15, 2015.
Pennsylvania Horticultural Society (PHS). 2015. Greening LandCare Program: Evidence of Success. http://phsonline.org/programs/landcare-program/evidence-of-success. Accessed June 10, 2015.
Seitz, J. and F. Escobedo. 2008. “Urban Forests in Florida: Trees Control Stormwater Runoff and Improve Water Quality.” School of Forest Resources and Conservation Department, UF/IFAS Extension. https://edis.ifas.ufl.edu/fr239. Accessed November 3, 2015.
Smith, D. 1999. “The Case for Greener Cities.” American Forests. Autumn 1999 v. 105 (3).
Wolf, K.L. 1998. “Urban Nature Benefits: Psycho-Social Dimensions of People and Plants.” University of Washington, College of Forest Resources Fact Sheet. 1(November).
Wolf, K.L. 1999. Grow for the Gold. TreeLink Washington DNR Community Forestry Program. 14(spring).
Wolf, K.L. 2003. Public Response to the Urban Forest in Inner-City Business Districts. J. Arbor 29(3):117–126.
Wolf, K.L. 2005. Business district streetscapes, trees, and consumer response. Journal of Urban Forestry 103(8): 396-400.
Wolf, K.L. 2007. “City Trees and Property Values”. Arborist News (August):34–36.
Ulrich, R. S. 1984. “View through a window may influence recovery from surgery.” Science, 224, 420–421.
US DOT, FHWA. 2015. Bicycle & Pedestrian Planning: Best Practices Design Guide. https://www.fhwa.dot.gov/environment/bicycle_pedestrian/publications/sidewalk2/sidewalks209.cfm. Accessed January 3, 2020.
Yu, Chia-Pin & Hsieh, Hsuan 2020. Beyond restorative benefits: evaluating the effect of forest therapy on creativity. Urban Forestry & Urban Greening 51: https://doi.org/10.1016/j.ufug.2020.126670
American Lung Association (ALA). 2015. State of the Air 2015. http://www.stateoftheair.org (accessed May 30, 2015).
Astrell-Burt, T., Feng, X. 2019. Does sleep grow on trees? A longitudinal study to investigate potential prevention of insufficient sleep with different types of urban green space. SSM - Population Health https://www.sciencedirect.com/science/article/pii/S2352827319301703
Coder, R.D. 1996. “Identified Benefits of Community Trees and Forests.” University of Georgia Cooperative Extension Service, Forest Resources Publication FOR96-39.
Dolan, RW. 2015. "Two Hundred Year of Forest Change: Effects of Urbanization on Tree Species Composition and Structure." ISA Aboriculture & Urban Forestry. 41 (3): 136-145
EPA U.S. Environmental Protection Agency. 2015. Heat Island Effect: Trees and Vegetation. http://www.epa.gov/heatislands/mitigation/trees.htm. Accessed May 30, 2015.
Kuo, F., and W. Sullivan. 2001. “Aggression and Violence in the Inner City: Effects of Environment via Mental Fatigue.” Environment and Behavior 33(4):543–571.
Kuo, M., Klein, S., Browning, M., Zaplatosch, J. 2021. "Greening for Academic Achievement: Prioritizing What to Plant and Where." Landscape and Urban Planning 206:103962.
Lovasi, G.S., Quinn, J.W., Neckerman, K.M., Perzanowski, M.S., & Rundle, A. 2008. “Children Living in Areas with More Street Trees have Lower Prevalence of Asthma.” Journal of Epidemiology & Community Health. 62:7(647-49).
North Carolina State University. 2012. “Americans are Planting Trees of Strength.” http://www.treesofstrength.org/benefits.htm. Accessed May 15, 2015.
Pennsylvania Horticultural Society (PHS). 2015. Greening LandCare Program: Evidence of Success. http://phsonline.org/programs/landcare-program/evidence-of-success. Accessed June 10, 2015.
Seitz, J. and F. Escobedo. 2008. “Urban Forests in Florida: Trees Control Stormwater Runoff and Improve Water Quality.” School of Forest Resources and Conservation Department, UF/IFAS Extension. https://edis.ifas.ufl.edu/fr239. Accessed November 3, 2015.
Smith, D. 1999. “The Case for Greener Cities.” American Forests. Autumn 1999 v. 105 (3).
Wolf, K.L. 1998. “Urban Nature Benefits: Psycho-Social Dimensions of People and Plants.” University of Washington, College of Forest Resources Fact Sheet. 1(November).
Wolf, K.L. 1999. Grow for the Gold. TreeLink Washington DNR Community Forestry Program. 14(spring).
Wolf, K.L. 2003. Public Response to the Urban Forest in Inner-City Business Districts. J. Arbor 29(3):117–126.
Wolf, K.L. 2005. Business district streetscapes, trees, and consumer response. Journal of Urban Forestry 103(8): 396-400.
Wolf, K.L. 2007. “City Trees and Property Values”. Arborist News (August):34–36.
Ulrich, R. S. 1984. “View through a window may influence recovery from surgery.” Science, 224, 420–421.
US DOT, FHWA. 2015. Bicycle & Pedestrian Planning: Best Practices Design Guide. https://www.fhwa.dot.gov/environment/bicycle_pedestrian/publications/sidewalk2/sidewalks209.cfm. Accessed January 3, 2020.
Yu, Chia-Pin & Hsieh, Hsuan 2020. Beyond restorative benefits: evaluating the effect of forest therapy on creativity. Urban Forestry & Urban Greening 51: https://doi.org/10.1016/j.ufug.2020.126670
