More Trees = Less Crime

Chicago’s Robert Taylor Homes is the largest public housing development in the world. The Robert Taylor Homes consist of 28 sixteen-story apartment buildings. Most of the complex is an urban desert– concrete and asphalt cover the spaces between the buildings– but there are pockets of trees here and there. In 2001, Frances Kuo and Bill Sullivan of the University of Illinois Human-Environment Research Laboratory studied how well the residents of Robert Taylor were doing in their daily lives based on the amount of contact they had with these trees.


Less crime
There were dramatically fewer occurrences of crime against both people and property in apartment buildings surrounded by trees and greenery than in nearby identical apartments that were surrounded by barren land. In fact, compared with buildings that had little or no vegetation, buildings with high levels of greenery had 48 percent fewer property crimes and 56 percent fewer violent crimes. Even modest amounts of greenery were associated with lower crime rates. The greener the surroundings, the fewer the number of crimes that occurred.
Greenery lowers crime through several mechanisms. First, greenery helps people to relax and renew, reducing aggression. Second, green spaces bring people together outdoors, increasing surveillance and discouraging criminals. Relatedly, the green and groomed appearance of an apartment building is a cue to criminals that owners and residents care about a property and watch over it and each other.
Stronger community
The study found that when compared to people who live in places without trees, residents of Robert Taylor Homes who live near trees have significantly better relations with, and stronger ties to their neighbors. They have more visitors, socialize more with their neighbors, know more people in their apartment building, and have a stronger sense of community than people who live in places without trees. They also like where they are living more, feel better adjusted to living there, and feel safer than residents who have few trees around them. Sullivan and Kuo’s team made 100 observations of outdoor common spaces in two public housing developments. They found people gathered in common spaces that contained trees significantly more often than they gathered in spaces that had no trees. These findings held true for adults, for children, and for adults supervising children.
Women who lived in apartment buildings with trees and greenery immediately outside also reported greater effectiveness and less procrastination in dealing with their major life issues than those living in barren but otherwise identical buildings. In addition, the women in greener surroundings found their problems to be less difficult and of shorter duration. Thus it seems that trees help poor inner-city residents cope better with the demands of living in poverty, feel more hopeful about the future, and manage their most important problems more effectively.
Less violence
The study also found that residents of Robert Taylor Homes who live near trees have significantly less violence in their homes than people who live in places without trees. Of 200 residents interviewed, 14 percent of those in non-green areas said that they had hit their children in the past year, compared to only three percent of residents in areas with trees. And 22 percent of women from non-green areas said they had engaged in violence in the last year, compared to 13 percent of those in planted areas.
Sullivan and Kuo believe that the urban forest provides a setting in which neighbors get to know one another. In doing so, they build stronger relationships among themselves, and build a support system that provides alternatives to violence.
Kuo and Sullivan have also since completed follow-up studies examining the benefits to children of living in close contact with urban forests.
* Do children who have more contact with trees do better in school?
* Do they play in more cooperative, collaborative ways?
* Is their overall development better than children who live with few trees around them?
For complete findings, visit the University of Illinois' Landscape and Human Health Laboratory.
The information here is from the original scientific articles:
* Kuo, F.E. & Sullivan, W.C. (2001). Environment and crime in the inner city: Does vegetation reduce crime? Environment and Behavior, 33(3), 343–367.
* Kuo, F.E. & Sullivan W.C. (2001). Aggression and violence in the inner city: Impacts of environment via mental fatigue. Environment & Behavior, 33(4), 543–571.
* Kuo, F.E., Sullivan, W.C., Coley, R.L., & Brunson, L. (1998). Fertile ground for community: Inner-city neighborhood common spaces. American Journal of Community Psychology, 26(6), 823–851.
* Kuo, F.E. (2001). Coping with poverty: Impacts of environment and attention in the inner city. Environment & Behavior, 33(1), 5–34.
This research was supported by the University of Illinois and by the USDA Forest Service Urban and Community Forestry Program on the recommendation of the National Urban and Community Forestry Advisory Council. More questions? Contact Frances E. Kuo at the University of Illinois at Urbana-Champaign, Landscape and Human Health Laboratory, 1103 S. Dorner Drive, Urbana, Illinois 61801.

Related Resources:
On Crime As Science (A Neighbor At a Time)