Definition: Pruning off the terminal or “head” growth of a plant, especially a tree. Heading back is a general term, whose subcategories include "topping" and "pollarding." Topping is performed on large old trees as an inexpensive alternative to their full removal. Pollarding, in contrast, is performed for aesthetic reasons. Pollarding begins when a tree is young, and continues throughout the life of the tree.
Also Known As: pollarding, topping (note that "topping" has acquired a rather negative connotation)
Examples:
"Heading back the terminal shoot of a young tree will cause the leader (main trunk) to branch - but note that you may get more new leaders than you want, so be ready to thin out the extras." -- Floridata.com
