How to Prune Maple Trees
Most common in the northeastern United States, maple trees are lovely and attractive specimens—at least if they're well maintained. To keep maple trees looking their best and producing new growth, trim and prune them. With a little work and effort, your maple trees will perform at their very best.
Pick the best time of year for pruning. Maple trees produce sap—lots of sap—which seeps out when the branches are cut. This sap makes it difficult to work on pruning the tree, so it's best to pick times of year when the sap supply will be at its lowest point. Generally, this is either going to be mid-summer or late fall.
Wear clothing you can throw away, because if you get the sap on your clothes, it won't come out. Always wear gloves and protective eye gear too.
Get rid of dead branches littered throughout the tree, which will give you a better idea of how the live branches look and where you need to trim and cut to maximize the aesthetic value of your maple.
Choose suitable branches for cutting. Specifically, you should look for branches that grow up or down along the same angle as the tree trunk or branches that grow into or against other branches. Removing these will help with the canopy spread of the tree.
Cut back the branches. Done in two stages, first make an upward cut from the underside of the branch. Cut roughly a foot out from the trunk of the tree and about halfway through the branch. Make the second cut from the top and go deep enough to meet the initial cut, thus making sure your hands are out of the way when the branch finally falls.
Remove the branch stub. Make a single cut going downward and slightly away from the tree trunk. This cut will also help prevent the bark from peeling back from the maple tree around the exposed stump.
Thin out the interior. Once you cut the branches that need to be removed, thin out the interior portion of the tree by trimming back the smaller branches and twigs. The objective here is to make sure that plenty of light gets to the interior of the tree.