Stockton has a lot of crime; this is no secret. Stockton also benefits from a tremendous tree canopy and was once named “Best Tree City.” Is there a correlation between crime and trees? Yes, but maybe not the kind you were thinking of. While Stockton suffers from soaring crime rates, evidence shows the presence of trees can have a positive effect on public safety. Obviously, planting trees won’t magically stop crime, but it’s important to understand that there is a relationship between public safety and good tree coverage.
In the past there have been conflicting theories on the relationship between crime and greenery. Some studies have suggested more vegetation provides criminals more places to hide, increasing crime rates. On the other hand, some have suggested that the presence of trees and landscaping has something of a “broken windows” effect, deterring crime by showing criminals that people care about the neighborhood. Turns out, both of these theories may hold some weight, according to a new study of the relationship between trees and crime.
In a recent report in Landscape and Urban Planning, researchers studying Baltimore, Maryland found a clear inverse relationship between tree coverage and crime. Specifically, the study concluded that overall, a 10% increase in tree coverage was associated with a roughly 12% decrease in robberies, burglaries, thefts, and shootings. Baltimore, setting for the best TV show in history, The Wire, suffers from a bad crime reputation just like Stockton, so these results are somewhat telling for our community, especially since our city’s trees are suffering from a lack of maintenance.
But not all types of vegetation are associated with lower crime rates. Within the study area, the researchers found that areas with more unkempt and overgrown vegetation experienced an increase in crime rates, showing that not all crime fighting flora are created equal. Clearly, healthy trees are better at deterring criminal activity than overgrown bushes and shrubs.These findings are consistent with other studies done on trees and crime, as noted by the Atlantic Cities.
Just to be clear, the argument here is not that places with trees are simply safer than those without trees. Many will read this and argue that older neighborhoods with mature trees are not nearly as safe as newer suburbs with no tree coverage. This argument may be true, but misses the point of this kind of study. The research controls for other factors affecting crime rates such as income level and race by using regression analysis, meaning that the researchers are able to isolate the effects of trees on crime when all other factors are equal. It is best to interpret the study’s findings in the following way: a neighborhood that has 10% more tree coverage than another neighborhood with the same socioeconomic demographics will experience 12% less crime than the comparable neighborhood. I have written before about the positive correlation between property values and trees, and we now have proof that trees can also fight crime.
While Stockton is not Baltimore, the information provided by this study is still relevant, especially since the city’s trees face dwindling maintenance budgets. The big takeaway here is not that we need to plant more trees to help stop crime. Instead, the study shows that we cannot afford to let our existing trees fall into a further state of disrepair. On top of policing shortages and stagnant economic conditions, allowing our tree canopy to decrease could compound our already difficult crime problem.