All too often a tree is planted in the landscape and then pretty much left alone. In order for these young trees to grow into strong, healthy, safer trees. There should be some structural training done early on. Starting in the first 15 years of a trees life is the best time to structurally prune your trees. In these early years the young trees are vigorous and can tolerate some harder pruning and larger pruning cuts can heal more rapidly.
A few things that should be done is to remove any dead or broken branches. A strong leader should be selected and any competing leaders should be subordinated (proper pruning techniques should be observed) and/or eventually removed. What we are looking to do is to encourage strong vertical growth and good trunk taper. Poor attachments should also be removed in these early years. If they are left on until maturity, they have a high risk of failure. Also if the are to be removed in later stages, you end up with large pruning cuts that will not heal as rapidly. If branch failure occurs you cannot control the extent of the damage done by a torn limb which can result in a weakened tree. One last thing about removing poor attachments, it can reduce the likely hood of installing tree support systems later on.
This Manitoba Maple was not planted there by people, nor was it really cared for. The only attention this tree really had was getting side pruned to avoid conflict with utility lines. This tree should have probably been removed before it failed. It was full of defects and ended up failing under a surprise snowfall in the Spring. If this tree had been planted in an appropriate spot and had been cared for properly in the beginning, the chances of it surviving a surprise snowfall would have been much greater.
If you have young trees and you are not sure what to do, get in touch with us. Our ISA Certified Arborists would be happy to get your trees going in the right direction.