How Large of a Branch Can You Trim off of a Tree?

Tree Branch Size

• If a tree branch is diseased, you should remove it no matter its size to prevent the disease from spreading to the rest of the tree or garden. If the branch is larger than 2 inches in diameter, you'll need to use a pruning saw. However, if the pruning saw isn't enough for a branch several inches or more in diameter, a chain saw is necessary and a professional is recommended to do the job, according to North Carolina State University.

How Much to Remove at Once

• Young trees, which grow rapidly, are able to seal off pruning wounds faster than mature trees. Once a tree is established, it has less energy to close wounds -- meaning that large wounds are vulnerable to insect infestations and decay on mature trees. For this reason, it's safer to avoid pruning mature trees; training young trees is preferable to corrective pruning of mature trees. If you must keep a mature tree from crowding your yard or garden, regular, light trims are safer than cutting off a lot of tree tissue and several large branches at all once.

Reasons to Remove Branches

• As long as large tree branches are healthy and not overgrown in their allocated space, you should leave them alone. The main reasons to remove large branches on a mature tree are death and disease. You should also remove branches if they're dangerous; for instance, large branches near power lines require a professional to remove them before they damage the lines. Crossed tree limbs that are rubbing together can also cause problems, so it's best to remove one of them or make thinning cuts to allow healthy aeration.

How to Prune Large Branches

• The key to removing large branches is reducing tear to speed the recovery process. The first step is making a small notch cut at the bottom of the branch, 2 to 3 feet from the trunk; this cut should only slice through about 1/4 of the branch's diameter. Make the second cut a few inches outside the first cut, starting at the top and working your way down until you either cut through the branch or it breaks under its own weight. With the outer portion of the branch now gone, perform the final cut close to the trunk, just outside the swollen branch collar.