Crown reduction pruning is most often used when a tree has grown too large for its permitted space. Crown reduction is not the same as 'topping' a tree. Topping a tree means cutting off the top at a certain level. The tree looks unsightly and butchered because the main stem or stems terminate suddenly where the cut is made. More importantly the large cuts associated with topping allow diseases and insects to quickly enter the tree and cause decay. In contrast, crown reduction involves cuts spread out throughout the crown so major stems are not cut off. Instead, small parts of branches are cut where the branch divides, leaving the tree a way to close off decay-causing organisms and heal strongly. The branches that are removed are usually the farthest ones out. This is because the weight of these branches has the greatest amount of leverage on the branch and in turn, on the whole tree. In this way, weight is removed so as to allow the tree to heal, remain attractive, and keep relatively compact so that it does not become too top-heavy or lose large branches. Crown reduction is a perfect solution for those who wish to keep trees that are especially close to their house or business and do not feel that 'trimming up' will suffice to ensure the tree's health and safety. Crown reduction focuses on encouraging growth lower in the canopy, thus keeping the center of gravity low over the long-term. Crown reduction differs from the standard 'limbing up' style of trimming in that the lower branches are retained as weight is removed above.
Lifting is the process of clearing out the lowest branches up to a certain level. Commonly used on Pines or evergreen trees to raise the lowest of the branches, or the skirt, to a higher level allowing access under the tree and a more distinct appearance.