Bough: the shoulder that divides a body into a trunk and arms, applicable to men, trees and ships. A bough of insufficient strength to branch (or limb) is a bulge, or a bunch (as in bunched-up muscles), or a burgeoning effort. It is only a bough when it extends itself and stretches out into finer and finer twigs, then into fingers, then holds fruit into the air or cups the rain. We say that branches bow down with fruit. We mean that they bough down. When trees are spoken of in this way, it is to acknowledge that they are men — well, men and women together in one form.
MacIntosh Apple Tree, Vernon, Canada