In the Canadian oiltown of Calgary, some residents are vociferously protesting city efforts to plant more trees because they're worried these trees will increase crime. Officials had planned to put 15 saplings in a small park, but had to stop after only eight were planted after meeting fierce resistance from a handful of locals, according to the CBC. "If you give people more places to hide, more naughty things will be done," said resident Ellen Burgess, who went door-to-door to get others to back her anti-tree campaign.
"They're using our park as a toilet," said one resident to CTV, while Burgess claimed to have found "a makeshift crackpipe" as well as other undesirable items in the park's shady grove.
Protesting trees, for fear of burglars and other criminals using them as cover, admittedly sounds silly (and has already sparked a lot of joking on social media). But the truth is that these residents' concerns aren't coming out of nowhere. For years now, and in places across North America, people have worried that more trees equals more crime.
"There's a long history of thinking trees and crime go hand-in-hand," said David Wachsmuth, assistant professor of urban planning at McGill University in Montreal. People have worried that urban greenery could potentially give criminals a place to hide.
"It's not just literally creeping in the bushes," Wachsmuth told me over the phone. "It obstructs sightlines. For that reason, tree or plant removal has been a crime mitigation strategy, in inner cities in particular."
Read More: How British Columbia Is Moving its Trees
He added that the other major concern lines up with the "broken windows" theory of crime: that, in places where vegetation is growing wild and out-of-control, a general lack of care will contribute to greater lawlessness. (Still, this probably isn't the sentiment of Calgary residents complaining about some saplings, Wachsmuth acknowledged.)
Regardless, this fear of trees is unfounded. Urban green spaces don't just help clean the air and cool the city—they could actually fight crime.
One study, published in 2013 in Landscape and Urban Planning, found that urban areas with well-maintained greenery also had lower rates of assault, robbery, and burglary (but not theft). Another, published in the same journal, looked at the relationship between having a well-tended front yard and crime in Baltimore. The presence of yard trees, garden hoses or sprinklers, and lawns, were all found to be negatively associated with crime.
If anything, Calgary's troubles highlight the importance of public consultation, Wachsmuth said (officials there have said they did consult residents before planting). After this hiatus, the city plans to finish planting trees in the area, a spokesperson confirmed to Motherboard.
And actually, if Calgarians are worried about burglars in the bushes, they should welcome more trees: creating a nice green space will draw more people to the park. "Public spaces that have more greenery tend to be used more," Wachsmuth said. "If you think about the factors that create a safe environment, one is that there's a lot of people out and about."
And that, in turn, can contribute to less crime.
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