Here is an interesting article from Scientific American titled Forests Transition as New England Warms:
"...In Canada and the Pacific Northwest, vast stretches of pine are being denuded by mountain pine beetles marching eastward.
In the upper Midwest, deer and earthworms are flourishing in the warmth, stripping the forest groundfloor and pushing out natural conifers.
In New England, the majestic hemlocks that were grist for Longfellow and Frost are doomed by the steady advance of a pest in warmer winters.
"To see hundreds of acres of dead forest like this in New England is remarkable," said Foster.
He moved with long strides through a thick underbrush of huckleberry and cat brier recently to a crest of the island, crowned with ashen-colored trunks of dead oak. The view of dead trees, he said, was "startling." ...(Cont.)...