Trees on the frontline, fighting crime to make our neighborhoods safer

As if our trees don’t do enough for us already—like conserve energy, clean our water and air, and improve home values—a new study shows they also fight crime.

Geoffrey Donovan and Jeffrey Prestemon of the U.S. Forest Service’s Pacific Northwest (PNW) and Southern Research Stations used data from the Portland Police Bureau to analyze crimes at 2,813 single-family homes in Portland between 2005 and 2007.

Eliminating factors such as the size or age of the home, whether or not there were barriers around the home, or whether the home had a burglar alarm, they were able to study the correlation between trees and crime rates. They considered dozens of variables such as the size, span and location of the trees.

Their conclusion? Large street and yard trees reduce crime.

“We believe that large street trees can reduce crime by signaling to a potential criminal that a neighborhood is better cared for and, therefore, a criminal is more likely to be caught,” Donovan explained.

The study concluded that every 1,000 homes will have 4.5 fewer crimes per 100 square feet of canopy cover. For example, with a 35-foot tree along the street in front of every house, you’ll have 45 fewer crimes per 1,000 homes. With a 50-foot tree along the street in front of every house, you’ll have 90 fewer crimes per 1,000 homes.

You can read more about the study in Molly Hottle’s story on OregonLive, in which Friends of Trees’ Brighton West points out that in addition to the crime-reduction benefits that trees provide themselves, meeting your neighbors at a planting event also makes a neighborhood safer, since neighbors who know each other tend to look out for each other.

Geoffrey Donovan’s previous study, also conducted in Portland, showed that trees can increase a home’s value by more than $7,000.

So if you haven’t signed up to buy a street or yard tree yet, don’t wait. Find out for yourself all the benefits that your tree can bring to you and your neighborhood.

–TR