This summer we had numerous smaller, but high intensity storms blow through the Milwaukee area, leaving widespread tree damage in their wake. Tree damage can occur in a variety of ways, such as by weakly rooted trees tipping over, trees splitting at weak stem unions, or limb breakage at areas where long limbs have excessive weight.
When pruning trees to reduce likelihood of storm damage, one of the most effective methods is to shorten the length of longer horizontally growing limbs. In our urban landscape trees tend to grow where there is less competition for light and they often spread out with longer horizontal limbs that may ultimately prove to become problematic and weak over time. The biggest long extended limb issues tend to occur with trees such as willows, silver maples, box elders and honey locust trees. The problems with heavily weighted limbs are certainly not exclusive to these selected species, and can develop on other trees as well.
By cutting weight off heavy limbs the stouter remaining portions of the limb and overall more uprightly growing tree is able to cope with punishing winds, snow and ice buildup. Our arborists look for proper places to cut the limbs back. Since every tree is different in size, structure, and biology, there is no right answer. But a good rule of thumb might be to reduce the length of the problematic branch by 25%, cutting back to a strong upright growing lateral branch. This will make the tree sound, give it a proper pruning cut and ensures the tree remains natural looking aesthetically.
Weight reduction is also a tool we use on older trees with structural issues that are showing concern such as decay or cavities. Removing significant weight from outer limbs can help prolong the life of a larger tree and can be a good alternative to outright removal.
When our arborists are reviewing trees for pruning, weight reduction pruning is one of the many considerations that we look at when evaluating whether or not a tree is structurally sound. Our team of certified arborists can provide evaluations on mature trees to help make decisions. If you are interested in a tree risk assessment for your tree, contact us. We will be happy to help.