Deep in the woods, the whine of chain saws pierced the fall air, and Steve Garcia shouted a warning to fellow loggers as a 40-foot pitch pine crashed to the ground. He was chopping down trees to save the forest as part of New Jersey’s effort to beat back an invasion of southern pine beetles.

In an infestation that scientists say is almost certainly a consequence of global warming, the southern pine beetle is spreading through New Jersey’s famous Pinelands.

It tried to do so many times in the past, but bitterly cold winters would always kill it off. Now, scientists say, the winters are no longer cold enough. The tiny insect, firmly entrenched, has already killed tens of thousands of acres of pines, and it is marching northward.

Scientists say it is a striking example of the way seemingly small climatic changes are disturbing the balance of nature. They see these changes as a warning of the costly impact that is likely to come with continued high emissions of greenhouse gases.

The disturbances are also raising profound questions about how to respond. Old battles about whether to leave nature alone or to manage it are being rejoined as landscapes come under stress.

From The New York Times: https://www.nytimes.com/2013/12/02/science/earth/in-new-jersey-pines-trouble-arrives-on-six-legs.html?pagewanted=1&_r=3&src=un&feedurl=https://json8.nytimes.com/pages/national/index.jsonp&