Canopy and Crime Canopy and Crime

Frances E. Kuo A study conducted by Natural Resources & Environmental Sciences University of Illinois at Urbana-Champaign

The Cooperative State Research, Education and Extension Service, U.S. Department of Agriculture The USDA Forest Service Urban and Community Forestry Program on the recommendation of the National Urban and Community Forestry Advisory Council With funding from

Take home message

The more vegetation outside a residence, the lower its crime rate. Take home message

Why Study Canopy and Crime? The Approach The Findings So What? Presentation outline

Why Study Canopy and Crime?

Dense woods and shrubs can conceal criminal activity.

Such dense vegetation evokes both general fear and fear of crime.

Removing greenery to deter crime is a common practice.

But is indiscriminately clearing greenery really a wise policy?

Not all vegetation blocks views.

In fact, vegetation that allows for visibility might inhibit crime.

Such green spaces might inhibit crime because they bring people together outdoors bring people together outdoors

Such green spaces might inhibit crime because they bring people together outdoors bring people together outdoors lessen mental fatigue, irritability, and lessen mental fatigue, irritability, and impulsiveness impulsiveness

Where would you feel safer?

Can vegetation in the common areas outside a residence actually reduce criminal activity?

The Approach

The Ida B. Wells development in Chicago was chosen as the research site because buildings and amount of outdoor common buildings and amount of outdoor common space are similar; only vegetation quantity space are similar; only vegetation quantity differs differs

The Ida B. Wells development in Chicago was chosen as the research site because buildings and amount of outdoor common buildings and amount of outdoor common space are similar; only vegetation quantity space are similar; only vegetation quantity differs differs vegetation does not block views vegetation does not block views

Characteristics of the residents here were important too. They are randomly assigned to these They are randomly assigned to these buildings. buildings.

Characteristics of the residents here were important too. They are randomly assigned to these They are randomly assigned to these buildings. buildings. They are similar in personal characteristics. They are similar in personal characteristics.

Method Police reports from 98 buildings were Police reports from 98 buildings were collected. collected.

Method Police reports from 98 buildings were Police reports from 98 buildings were collected. collected. Building common areas were rated for Building common areas were rated for quantity of vegetation. quantity of vegetation.

Common space with a low level of vegetation Common space with a high level of vegetation Measuring quantity of common space vegetation

Method Police reports from 98 buildings were Police reports from 98 buildings were collected. collected. Building common areas were rated for Building common areas were rated for quantity of vegetation. quantity of vegetation. The relationship between quantity of The relationship between quantity of vegetation and crime rate was analyzed. vegetation and crime rate was analyzed.

The Findings

LowMediumHigh # of property crimes Quantity of vegetation Buildings with more vegetation had fewer property crimes

LowMediumHigh Quantity of vegetation Canopy and Crime Buildings with more vegetation had fewer violent crimes # of violent crimes

LowMediumHigh Quantity of vegetation Buildings with more vegetation had fewer crimes overall # of crimes overall

So What?

The more vegetation a building had, the fewer crimes – fewer property crimes, fewer violent crimes, and fewer crimes overall.

Common areas with high-canopy trees and grass: are gathering spaces for neighbors are gathering spaces for neighbors

Common areas with high-canopy trees and grass: are gathering spaces for neighbors are gathering spaces for neighbors can foster states of mind that are less prone to can foster states of mind that are less prone to violence violence

Not only does vegetation make neighborhoods more attractive, it may make them safer!

To improve the quality of life for the many people who live in poor urban neighborhoods…

We must work together–planting, protecting, and maintaining urban vegetation.

Suggestions for urban property owners, planners, policy makers, and developers: think twice before removing trees or think twice before removing trees or vegetation for security reasons vegetation for security reasons

Suggestions for urban property owners, planners, policy makers, and developers: think twice before removing trees or think twice before removing trees or vegetation for security reasons vegetation for security reasons landscape buildings with vegetation that does landscape buildings with vegetation that does not block views not block views

Suggestions for urban property owners, planners, policy makers, and developers: think twice before removing trees or think twice before removing trees or vegetation for security reasons vegetation for security reasons landscape buildings with vegetation that does landscape buildings with vegetation that does not block views not block views maintain vegetation to preserve visibility maintain vegetation to preserve visibility

Support tree planting and tree care efforts in the inner city.

In harsh environments, a little green can go a long way.

Caring for trees means caring for people!

To share this information with others: Copies of this presentation and other, written materials for nonscientific audiences may be obtained at Copies of this presentation and other, written materials for nonscientific audiences may be obtained at To quote this information in print, please consult the original scientific journal article: To quote this information in print, please consult the original scientific journal article: Kuo, F.E., & Sullivan, W.C. (2001). Environment and crime in the inner city: Does vegetation reduce crime? Environment & Behavior, 33, Available at

To learn more: On details of the original study Kuo, F.E., Sullivan, W.C. (2001). Environment and crime in the inner city: Does vegetation reduce crime? Environment & Behavior, 33, On problems with dense vegetation Fisher, B.S., Nasar, J.L. (1992). Fear of crime in relation to three exterior site features: Prospect, refuge, and escape. Environment & Behavior, 24, Michael, S.N., Hull, R.B. (1994). Effects of vegetation on crime in urban parks. Blacksburg: Virginia Polytechnic Institute, Department of Forestry. Schroeder, H.W., Anderson, L.M. (1984). Perception of personal safety in urban recreation sites. Journal of Leisure Research, 16, Talbot, J., Kaplan, R. (1984). Needs and fears: the response to trees and nature in the inner city. Journal of Arboriculture, 10,

On tree removal policies to decrease crime Pluncknett, T.F.T. (1960). Edward I and criminal law. Cambridge University Press. Weisel, D.L., Gouvis, C., Harrell, A.V. (1994). Addressing community decay and crime: Alternative approaches and explanations. Washington, DC: The Urban Institute. On vegetation and decreased incivilities Brunson, L.B., Kuo, F.E., Sullivan, W.C. (2001). Resident appropriation of defensible space in public housing: Implications for safety and community. Environment & Behavior, 33, Stamen, T. (1993). Graffiti deterrent proposed by horticulturalist [press release]. Riverside: University of California, Riverside. To learn more:

On vegetation and increased surveillance Coley, R.L., Kuo, F.E., Sullivan, W.C. (1997). Where does community grow? The social context created by nature in urban public housing. Environment & Behavior, 29, 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, On mental fatigue and violence Kaplan, S. (1987). Mental fatigue and the designed environment. In J. Harvey & D. Henning (Eds.), Public environments (pp ). Washington, DC: Environmental Design Research Association. Kuo, F.E., & Sullivan, W.C. (2001). Aggression and violence in the inner city: Impacts of environment via mental fatigue. Environment & Behavior, 33, To learn more:

On vegetation and mental fatigue Cimprich, B. (1993). Development of an intervention to restore attention in cancer patients. Cancer Nursing, 16, Hartig, T., Mang, M., Evans, G.W. (1991). Restorative effects of natural environment experiences. Environment & Behavior, 23, Kaplan, R. (1984). Wilderness perception and psychological benefits: An analysis of a continuing program. Leisure Sciences, 6, Lohr, V.I., Pearson-Mimms, C.H., Goodwin, G.K. (1996). Interior plants may improve worker productivity and reduce stress in a windowless environment. Journal of Environmental Horticulture, 14, Miles, I., Sullivan, W.C., Kuo, F.E. (1998). Prairie restoration volunteers: The benefits of participation. Urban Ecosystems, 2, Tennessen, C., Cimprich, B. (1995). Views to nature: Effects on attention: Journal of Environmental Psychology, 15, To learn more:

Other questions? Contact Frances E. Kuo, Ph.D. The University of Illinois at Urbana-Champaign Landscape and Human Health Laboratory 1103 S. Dorner Drive, MC-636 Urbana IL 61801