Traffic Calming

• Trees can calm traffic and reduce vehicle speeds by appearing to narrow the width of the roadway. In an area where streets were widened and trees were not present, accidents increased by almost 500% within an 8-year period.Swift, P., Painter, D., and Goldstein, M. (1997). Residential street typology and injury accident frequency. Presented at the Congress for New Urbanism, June 1997.

Lower Stress

• The presence of trees along streets decreases stress levels while commuting, and in turn, reduces the likelihood of aggressive driving habits.Parsons, R.L., Tassinary, G., Ulrich, R.S., Hebl, M.R., and Grossman-Alexander, M. (1998). The View from the Road: Implications for Stress Recovery and Immunization. Journal of Environmental Psychology, 18, pp. 113-140.

Walking and Biking

• Tree lined streets and sidewalks encourage residents to walk and ride bikes, rather than drive personal vehicles due to the reduced urban heat island effect.Tilt, J., Unfried, T., and Roca, B. (2006). Neighborhood greenness, walkable destinations and health. Dissertation. University of Washington.

Pavement Protection

• By selecting the right tree species for a given area, the pavement damage typically caused by tree roots can be mitigated and spending on infrastructure repair will decrease.Randrup, T.B., McPherson, E.G., and Costello, L.R. (2001). A review of tree root conflicts with sidewalks, curbs, and roads. Urban Ecosystems, 5, 209-225.