"People have an intuitive sense that trees are good things," Geoffrey Donovan said. "Being a soulless economist, I like to quantify things. 'Trees are nice' isn't a very useful statement. You need to know how nice and in what sorts of circumstances."
Donovan, who works for the U.S. Forest Service in Portland, Ore., is trying to measure how urban trees affect the quality of life. He has looked for correlations between tree-canopy cover and the risk of premature births, and is studying the role of trees in managing storm-water runoff. The article that has received the most attention, though, deals with the effect of trees on crime in Portland. Co-authored with Forest Service colleague Jeffrey Prestemon, it was published last fall in the journal Environment and Behavior.
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