Made for Each Other

Some trees and birds are made for each other. Take, for example, the whitebark pine, a timberline tree that graces the moraines and ridgetops of the northern Rockies and the Sierra Nevada-Cascades system. This lovely five-needled pine, long-lived and rugged though it is, cannot reproduce without the help of Clark''s nutcracker. And the nutcracker, though it captures insects in the summer and steal...