In this video, Ask This Old House landscape contractor Roger Cook shows the proper way to prune a branch without damaging the tree.
1. Trim tree branches with a sharp pruning saw using the three-cut method.
2. First, make an undercut into the bottom of the branch. Start cutting about 12 inches away from the tree trunk, and saw one-third of the way into the branch.
3. Then saw into the top of the branch about 2 inches farther out and beyond the undercut.
4. Continue cutting until the branch breaks free and drops to the ground.
5. Now make the third and final cut to trim away the remaining branch. However, be careful not to saw into the branch collar.
6. Carry away the severed pieces of the branch.