Assessing and Pruning Wind-Damaged Trees

Jacob Mares, Arborist and Horticulturist, Gardens on Spring Creek

The Front Range is no stranger to high wind events. Strong, high-pressure weather systems that form along the Rockies can send gales racing down through the foothills and out along the plains. Gusts as high as 100 miles per hour were recorded last month along the I-25 corridor, resulting in tree damage for many homeowners. Assessing this damage and deciding the best course of action can be tricky – keep an eye out for downed power lines or large hanging branches overhead. Always call an arborist if you feel the job could be dangerous!

If you have decided the work can safely be completed, take time to gather what you will need to remove the damaged area. Personal protective equipment such as gloves, a hard hat, and eye protection is key to safely performing the work. Any job performed over your head or from a ladder can quickly become hazardous, so always have another person on-site to assist. A sharp set of pruners or saw will ensure that the pruning cut heals properly and that you are not further damaging the tree. 

Large, broken branches that require the entire branch to be removed should be cut in sections, from the tip back, to prevent tearing of the bark on the trunk. This alleviates pressure at the attachment point and provides room to make a proper pruning cut (see illustration). This cut should reflect the angle of the branch bark collar or 45 degrees away from the trunk starting at the top, near the collar. Never cut the branch “flush” to the trunk. This takes away the tree’s natural ability to compartmentalize the wound and can lead to further problems. Branches that have been damaged further away from the trunk can be pruned back to the next branch union, or the closest bud. 

If a damaged branch has torn the bark at the point of the attachment (see illustration) it is important to remove the branch and any jagged bark. Using a sharp knife, carefully cut around the damaged area leaving a smooth cut. Take care not to expose any more of the soft, green layer (cambium) below the bark. These wounds are more detrimental to the tree so take great care when repairing the damage. 

As you work to remove broken and damaged limbs, take care not to over prune the tree. Loss of more than a third of the tree’s canopy can result in reduced vigor and even death.