Trees can be a sizeable investment of hard earned dollars. One of the surest ways to protect and increase the value of your property is to prune the trees you plant every other year the first ten years after planting. These early years in the life of a tree are the years when fairly aggressive pruning yields the best results, and are the years when pruning is easiest.
The day you plant a tree, make up your mind that you will prune that tree every other year without fail during its first ten years. By doing so, pruning wounds will be small and heal quickly and you will be shaping a tree that will be much stronger during storms.
Try to avoid delaying the pruning of your tree. If you wait loo long it may become exceedingly difficult or impossible to achieve good structure and great beauty.
After the first ten years, pruning every 3 to 5 years by a skilled arborist should be sufficient to maintain sound structure. A tutorial on pruning by the University of Minnesota extension site is a good reference.