Article notes nascent awareness of the ecological impact of our urban forests

An article in The Guardian observes a nascent awareness of the ecological impact of our urban forests street trees forests.  I'll go with urban forests, which seems to be the au courant term for trees we plant along streets and in parks.  The article has an east coast focus, but the lessons are apropos for any area.

Though it may be too soon to call it an urban wildlife movement, initiatives focused on urban biodiversity seem to be catching on. The U.S. Forest Service, which once laughed off the idea that anything urban could be wild, now supports a growing urban forest program. Urban ecology and urban wildlife programs are also proliferating on university campuses. There’s a "Nature of Cities" blog, launched in 2012. University of Virginia researchers recently announced the beginning of a Biophilic Cities Network devoted to integrating the natural world into urban life... 

...a single pair of Carolina chickadees needs to bring 6,000-9,000 caterpillars to the nest to rear a clutch of a half-dozen nestlings. Black-capped chickadees probably need more. If you want the birds, he says, you need the caterpillars, and to get the caterpillars you need the right trees. "All plants are not created equal," [Tallamy] says. "Natives are more likely to be beneficial than non-natives, but even among natives, there are differences." 

Accommodating wildlife in cities doesn’t necessarily require massive investment.... You can bring in more birds...just by breaking up endless lawns with the right kinds of shrubs, to create structure and variety. Mowing those lawns a little less often — not weekly but every two or three weeks — will increase the population of native bees and other pollinators.