Cold-Resistant Trees

The Appalachians are an old, worn-down mountain chain that runs down the eastern side of North America. The ecology of the Appalachians is fascinating. For example:

Ecologists have tested many species of Appalachian trees to see how much cold they can survive. As you’d expect, for many trees the killing temperature is just a bit colder than the lowest temperatures at the northern end of their range. That makes sense: presumably they’ve spread as far north—and as far up the mountains—as th...