The Oregonian reports this month:
Researchers used satellite images to compare tree cover around the houses of 5,696 women who gave birth in Portland in 2006 and 2007. Pregnant women living in houses graced by more trees were significantly less likely to deliver undersized babies…
“Maybe it sounds a bit daft at first,” says lead author Geoffrey Donovan, a scientist with the U.S. Forest Service’s Pacific Northwest Research Station in Portland. But he says it’s plausible that having lots of trees nearby counteracts the stress experienced by pregnant women.
Studies in animals and people make clear that maternal stress is harmful to a developing fetus and can increase the probability of underweight birth. In a variety of human clinical trials, exposure to nature and greenery significantly reduced people’s stress levels and helped them withstand high-stress situations.
Boston Globe: “How the city hurts your brain” (1/14/09)
One of the main forces at work is a stark lack of nature, which is surprisingly beneficial for the brain. Studies have demonstrated, for instance, that hospital patients recover more quickly when they can see trees from their windows, and that women living in public housing are better able to focus when their apartment overlooks a grassy courtyard. Even these fleeting glimpses of nature improve brain performance, it seems, because they provide a mental break from the urban roil…
UMass Press: “Natural Land: Preserving and Funding Open Space”
Preserving areas of nature, open space, and trees and other vegetation can have psychological as well as physical health benefits for local residents. There is a growing body of research which points to the power of nature to restore people from the stress of modern life, including mental fatigue (Kaplan, Kaplan, and Ryan 1998; Frumkin 2001).
Downstreet.net: “Despite Tree City USA Honor Northampton Planting Lags”
Each year, the city removes more dead or hazardous trees than it replaces, leaving a net decrease in the population of our mature shade trees…