Globalization puts US forests as risk from pests

Scientists say they already are driving some tree species toward extinction and are causing billions of dollars a year in damage — and the situation is expected to worsen.

“They are one of the few things that can actually eliminate a forest tree species in pretty short order — within years,” said Harvard University ecologist David Orwig as he walked past dead hemlocks scattered across the university’s 5.8-square-mile research forest in Petersham.

[...] destruction would do away with a critical sponge to capture greenhouse gas emissions, shelter for birds and insects and food sources for bears and other animals.

Today’s connected world enables foreign invaders to cross oceans in packing materials or on garden plants, and then reach American forests.

Genetic engineering could also be applied to fight insects, said William Powell, a State University of New York College of Environmental Science and Forestry professor.