Although apple trees are generally quite carefree, they benefit from yearly pruning to keep them healthy and ensure their largest potential fruit harvest. Large apple trees can present some challenges when it comes time to prune them, however. If they haven't received proper care over the years, the pruning job facing you can be a big one. Broken branches, disease and improper pruning methods in the past can challenge even the most avid gardener. If your tree is large, overgrown and has signs of disease, you might consider hiring a professional arborist for the job.
Pruning Large Apple Trees
Prune apple trees during winter, after all leaves have fallen. Assess the pruning job before you begin to determine the number of dead or broken branches, to envision the shape you want for your tree and to plan for the tools you will need.
Cut broken and dead branches first by cutting them cleanly on the branch side of the collar--a raised area where the branch attaches to the trunk.
Trim off all branches that are 4 feet from the ground and lower.
Prune branches in the center of the tree to allow more light to enter and to provide better air circulation, which will help to prevent some diseases.
Cut suckers that grow from the tree's base all the way back to the trunk. Also cut shoots that point upward and downward from large branches you intend to keep. The goal is to create a globe-shaped tree with a strong trunk and leave only the best branches.