Stephen F. Arno

Westerners familiar with their forests may think they know the Douglas fir–but how well do they? Douglas firs are found in the continental northwest from British Columbia to as far south as Oaxaca, Mexico. They flourish in the Cascades, Rocky Mountains, Sierra, and other mountain ranges, as well as in desert valleys.<br><br> Incredibly hardy, this tree adopts various strategies to occupy more kinds of habitats than any other native tree, even becoming an uncontrollable invader in...