Any dead or damaged limbs or branches should be removed as soon as possible. If you are trying to promote growth, it’s best to avoid hot and dry seasons as well as extreme winter cold. Optimal time for pruning is late winter or early spring, just before the tree starts to bud. Pruning while the tree is dormant will result in a burst of new growth in the spring. Some trees, such as maple, walnuts, or birches, may “bleed” sap but this is not harmful and will stop when the leaves start producing.
If you want to prune for corrective reasons, such as a defective or deformed branches, trimming after the growth season, during the summer, is optimal.
Removing dead or damaged limbs and branches helps prevent pests and insects from entering the tree. It also helps increase air and sunlight, preventing diseases. Branches that cross over can cause tree damage by rubbing against each other and the smaller of the rubbing branches should be removed.
Low growing branches near sidewalks and driveways can cause safety hazards during storms and should be maintained at a proper height.
Careful thought and consideration should be taken before you begin pruning. Make a plan of exactly what limbs you are going to cut and how you’re going to do it. Each cut compromises the tree and opens it up to potential diseases and insect infestations. Prune only as much as is necessary and never more than 25% of a tree’s branches. Do not heavily prune trees or shrubs more than once a year. The tree needs time to recover after each pruning.
Most pruning can be done with tools such as hand pruners, loppers, and a pruning saw. Avoid cutting any of the main structural branches of the tree or shrub. Cut branches as close to the source as possible. Leaving a stub sticking out provides a place for insects and bacteria to hang out. Below is a picture from the Arbor Day Foundation to help you know where to cut branches so that the tree or shrub can recover without risk of insect infestation or disease.