Baltimore Ecosystem Study Cary Institute of Ecosystem Studies

2012 BES Annual Meeting Presentation and Poster Abstracts

The relationship between crime and vegetation across an urbanization gradient
Troy, Austin
Co-Authors: Austin Troy, Morgan Grove and Jarlath O'Neil-Dunne

Abstract: The extent to which trees and other urban vegetation influence crime is in debate in the literature. This project used geocoded crime point data and high resolution tree canopy data to address this question in Baltimore City and County, MD. Using spatially adjusted regression and controlling for numerous potential confounders, we found that there is a strong inverse relationship between tree canopy and an index we created of robbery, burglary, theft and shooting. We found that a 10% increase in tree canopy was associated with a roughly 12% decrease in crime. When we broke down tree cover by public and private ownership for the spatial model, we found that the inverse relationship continued in both contexts, but the magnitude was 40% greater for public than for private lands. Using geographically weighted regression we also found some spatial variation in the relationship between trees and crime. Geographic plots of pseudo-t statistics indicated that while there was a negative relationship between crime and trees in the vast majority of block groups of the study area, there were a few patches where the opposite relationship was true, particularly in a part of Baltimore City where there is an extensive interface between industrial and residential properties. It is possible that in this area a significant proportion of trees is growing in abandoned lands between these two land uses. We also conducted preliminary analysis to look at the relationship between indicators of yard maintenance and crime.