We in the nursery industry know that “trees are the answer.” Here is another piece of evidence. Researchers with the U.S. Forest Service did a study in Portland, Ore. and found that homes with large street trees out front have a lower incidence of crime. From the abstract of the study:

The authors estimate the relationship between trees and three crime aggregates (all crime, violent crime, and property crime) and two individual crimes (burglary and vandalism) in Portland, Oregon. During the study period (2005-2007), 431 crimes were reported at the 2,813 single-family homes in our sample. In general, the authors find that trees in the public right of way are associated with lower crime rates. The relationship between crime and trees on a house’s lot is mixed. Smaller, view-obstructing trees are associated with increased crime, whereas larger trees are associated with reduced crime. The authors speculate that trees may reduce crime by signaling to potential criminals that a house is better cared for and, therefore, subject to more effective authority than a comparable house with fewer trees.

The study’s conclusion was announced by the journal Science Daily and will be published in the scientific journal Environment & Behavior. It’s also received widespread mainstream publicity, from CNN, the Washington Post, the San Francisco Chronicle, and others. The full study can be downloaded here.