Green Spaces Facts

“Lawns cane be up to 60 degrees cooler than surrounding pavement.”
— The Lawn Institute 

Urban parks are more effective at cooling air temperature in an urban heat island than bodies of water, such as urban ponds. Urban green spaces are also less expensive than so-called “urban blue spaces” and provide other benefits such as noise cancellation, aesthetic appeal, and recreational spaces. 

Targino, Admir Créso, Guilherme Conor Coraiola, and Patricia Krecl. 2019. “Green or Blue Spaces? Assessment of the Effectiveness and Costs to Mitigate the Urban Heat Island in a Latin American City.” Theoretical & Applied Climatology 136 (3/4): 971–84. https://link.springer.com/article/10.1007/s00704-018-2534-1  

“A well designed landscape can reduce energy consumption by up to 25% providing cooling in the summer by releasing water vapor like natural air-conditioner and offer shade. In the winter trees and hedges provide windbreaks.”

• US Department of Energy – https://www.energy.gov/energysaver/energy-efficient-landscaping

American urban forests produce about 61 million metric tons of oxygen each year, enough for two thirds of the United States population. 

Nilsson, Kjell. Book – Forests, Trees, and Human Health. Springer Verlag, 2011. https://link.springer.com/book/10.1007/978-90-481-9806-1  

In some cities, like Moorestown, New Jersey, urban forests offset greater than 100% of human oxygen consumption. On average, a hectare of trees (100% tree canopy) provides oxygen for 19 people each year. On average, a hectare of trees (100% tree canopy) provides oxygen for 19 people each year.

Nowak, David, et al. “Oxygen Production by Urban Trees in the United States.” Northern Research Station, 2007, http://www.nrs.fs.fed.us/pubs/jrnl/2007/nrs_2007_nowak_001.pdf.  

Healthy landscapes with diverse plant cover can slow the flow of water during heavy rains. They absorb rainwater and prevent runoff and erosion. Replenishing groundwater supplies and reducing the burden on stormwater systems

– Lawn Institute

Sodding a landscape can reduce runoff volume by 25% and sediment loss by over 99%.  Krenitsky, E.C., M.J. Carroll, R.L. Hill, and J.M. Krouse. 1998. Runoff and sediment losses from natural and man-made erosion control materials. Crop Sci. 38:1042- 1046. https://acsess.onlinelibrary.wiley.com/doi/abs/10.2135/cropsci1998.0011183X003800040026x  

Lawns are incredibly important in rainwater drainage. In vegetation-free cities, roughly 60% of rainwater becomes surface runoff which can contribute to erosion and pollute water. In cities with lawns, only 5-15% of rainwater becomes surface runoff with the rest evaporating or being absorbed into the ground to be used by vegetation. 75 P. Bolund, S. Hunhamma. Ecosystem Services in Urban Areas. Ecol. Econ., 29 (1999), pp. 293-301 https://www.scirp.org/(S(i43dyn45teexjx455qlt3d2q))/reference/ReferencesPapers.aspx?ReferenceID=1768763

Hard surfaces lead to two to six times more runoff than soft, natural surfaces.  Dixon, K. K., and K. L. Wolf. 2007. Benefits and Risks of Urban Roadside Landscape: Finding a Livable, Balanced Response. Proceedings of the 3rd Urban Street Symposium (June 24-27, 2007; Seattle, WA). Washington D.C.: Transportation Research Board of the National Academies of Science. https://nacto.org/docs/usdg/benefits_and_risks_of_an_urban_roadside_landscape_dixon.pdf 

LESSEN FLOODING

Natural Grass has also been shown to reduce runoff and soil erosion from 6-18 times greater than bare soil.

• The Lawn institute

A dense stand of turfgrass reduces soil erosion and surface runoff, thus protecting water quality and improving soil stability​. (Crop, Forage and Turfgrass Management Magazine – Strategies for reducing inputs and emissions in turfgrass systems – Ross C. Braun1 Chase M. Straw2 Douglas J. Soldat3 Michael A. H. Bekken3, Aaron J. Patton4 Eric V. Lonsdorf5 Brian P. Horgan6)

EASIER BREATHING

One 5,000 square-foot grass lawn can provide enough oxygen daily to support 14 – 34 people.

• The Lawn Institute

Estimated total annual air pollution removal (of ozone, particulate matter, NO2, SO2, and carbon monoxide) by urban trees across 55 U.S. cities is 711,000 metric tons, representing $3.8 billion in public value”.   Nowak D.J., D.E. Crane, and J.C. Stevens. 2006. Air Pollution Removal by Urban Trees and Shrubs in the United States. Urban Forestry & Urban Greening 4: 115–23.

GREEN SPACE LOWERS STRESS

Individuals experience a greater degree of restorative experience and lower stress levels with greater duration and frequency of visits to green spaces.  Korpela, K.M., M. Ylén, L. Tyrväinen, and H. Silvennoinen. 2008. Determinants of Restorative Experiences in Everyday Favorite Places. Health & Place 14, 4:636-652.

Older adults who have more exposure to green common spaces report a stronger sense of unity among residents within their local neighborhood, and experience a stronger sense of belonging to the neighborhood.^{5 5. Kweon, BS, WC Sullivan, and R Angel. 1998. Green Common Spaces and the Social Integration of Inner-City Older Adults. Environment and Behavior 30, 6:832-858.}

Research has found that city residents who live adjacent to green space have lower levels of illness and disease than other people of similar income levels.  83. Mitchell, R., and F. Popham. 2008. Effect of Exposure to Natural Environment on Health Inequalities: An Observational Population Study. The Lancet 372: 1655-1660.

LANDSCAPING IS A GOOD INVESTMENT

Landscaping yields, on average, a 109% return on every dollar spent, much more so than other home improvements.  Journal of Environmental Horticulture – June 2011 – Economic, Environmental, and Health/Well-Being Benefits Associated with Green Industry Products and Services: A Review1 Charles R. Hall2 and Madeline W. Dickson3 Department of Horticultural Sciences Texas A&M University, College Station TX 77843