What happened to the trees on I-70 through Western Pennsylvania?
I was on the turnpike (I-76 (I think) and I-70) through Western Pennsylvania and noticed that a large number of trees appeared to be dead on both sides of the interstate far up the hill/mountainside. Is there a specific reason for that?
A-Best: http://www.pittsburghlive.com/x/pittsburghtrib/news/cityregion/s_457551.html
For three years, Tom Langen, a biologist at Clarkson University in Potsdam, N.Y., and other researchers have studied the birch trees for the New York Department of Transportation, looking for a cause of their declining health. Langen is preparing to publish results pinpointing road salt as the cause.
