Remedial tree care after the storm often involves restorative pruning. This type of pruning is about restoring and re-establishing the crown structure. Restorative pruning is often a multi-phase process requiring several years of judicious pruning and periodic monitoring.
The crown structure can be dramatically altered when a tree has sustained any canopy loss; even a single branch. Missing portions of a previously balanced and well-structured tree can result in changes in wind behavior as it passes through the crown. The structural integrity of the crown is compromised when previously sheltered inner branches are exposed to wind-loading. By strategically reducing end-weight on newly exposed branches, the negative effects of wind-loading can be mitigated.
Another aspect of restorative pruning is to monitor for response growth and to manage for vigorous re-sprout growth. When there is significant crown loss, the tree responds by producing an over-abundance of epicormic shoots. These shoots, also referred as water shoots or suckers, are fast growing, weakly attached to the tree, and do not have the same physiology as a normal branch. However, these shoots are necessary to restore lost energy reserves. Judicious pruning is vital to properly manage epicormic shoots which will eventually assume part of the crown structure. Over several pruning cycles, competing shoots are selectively thinned and dominant shoots managed.
These are just a few examples of how to manage a tree injured by a storm. Depending on the extent of storm damage, not all trees can be preserved and retained safely. Other factors to consider when deciding whether restorative pruning is a viable option include species, age, location of risk targets, overall health and condition of tree prior to storm damage, and budget constraints.
Before... and after.