<blockquote>One school of thought has it that inner-city trees and shrubs make convenient hiding places and covered escape routes for criminals. Another, supported by an increasing body of evidence, argues that urban foliage may actually reduce crime.</blockquote>
via <a href="http://arstechnica.com/science/2013/04/urban-planners-may-cry-bring-us-a-shrubbery-to-deter-crime/">Urban planners may cry “bring us a shrubbery” to deter crime | Ars Technica</a>.