Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Some city trees may discourage 'shady' behavior

New study explores relationship between urban trees and crime

Along with energy conservation and storm-water reduction, scientists may soon be adding crime-fighting to the list of benefits that urban trees provide.

Researchers with the U.S. Forest Service's Pacific Northwest (PNW) and Southern Research Stations have published a new study that suggests that certain types of city trees may help lower property and violent crime rates.

Their study—which is posted online in advance of its appearance in a forthcoming printed issue of the journal Environment and Behavior—is the first to examine the effects of trees and other factors on crime occurrence in Portland, Ore.

"We wanted to find out whether trees, which provide a range of other benefits, could improve quality of life in Portland by reducing crime, and it was exciting to see that they did," said Geoffrey Donovan, research forester with the PNW Research Station who led the study. "Although a burglar alarm may deter criminals, it won't provide shade on a hot summer day, and it certainly isn't as nice to look at as a tree."

Donovan and his colleague Jeffrey Prestemon, with the Southern Research Station, obtained crime data from the Portland Police Bureau from 2005 to 2007 and grouped the incidents into seven categories. They examined only crimes for which a physical address was given and paired this information with additional data obtained from aerial photographs, onsite visits, and the Multnomah County Tax Assessor's Office. Their sample of 2,813 single-family homes experienced 394 property and 37 violent crimes.

The researchers then conducted statistical analyses to explore the relationships among crime and more than two dozen variables they compiled, including the number and size of trees on a lot and the size of trees on surrounding areas. Of the tree variables analyzed, canopy size of both street and yard trees and the number of trees growing on a lot had the most effect on crime occurrence—large trees were associated with a reduction in crime, while numerous small trees were associated with an increase.

"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 said. "Large yard trees also were associated with lower crime rates, most likely because they are less view-obstructing than smaller trees."

In contrast, their analysis suggested that small yard trees might actually increase crime by blocking views and providing cover for criminals—an effect that homeowners can mitigate by keeping trees pruned and carefully choosing the location of new trees.

Donovan and Prestemon plan to continue this line of research and may conduct similar studies in other cities.

To view the study's abstract online, visit

The PNW Research Station is headquartered in Portland, Oregon. It has 11 laboratories and centers located in Alaska, Oregon, and Washington and about 425 employees.

Yasmeen Sands | EurekAlert!
Further information:

Further reports about: Urban Trees energy conservation storm-water reduction

More articles from Agricultural and Forestry Science:

nachricht Forest Management Yields Higher Productivity through Biodiversity
14.10.2016 | Technische Universität München

nachricht Farming with forests
23.09.2016 | University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Prototype device for measuring graphene-based electromagnetic radiation created

28.10.2016 | Power and Electrical Engineering

Gamma ray camera offers new view on ultra-high energy electrons in plasma

28.10.2016 | Physics and Astronomy

When fat cells change their colour

28.10.2016 | Life Sciences

More VideoLinks >>>