Trees are one of a homeowner’s most important assets.
They provide beauty to our neighborhoods, enhance property values, shade and cool our homes and reduce our energy bills. They also supply the oxygen we need to breathe. Trees mitigate climate change by trapping greenhouse gases and provide critical habitat for birds and wildlife. To keep them healthy and safe, trees need periodic maintenance—especially pruning. Pruning trees is much more than just clearance. Medium- and large-maturing trees need pruning to correct structural defects which can improve their ability to tolerate high winds. Now is always the time to prepare them for hurricane season.
Here are some tips for preparing your trees:
1. Remove severely damaged and potentially hazardous trees from your property.
If you have trees that are in poor condition or are leaning towards buildings or other targets needing protection, consider having them removed. An ISA-certified arborist can assist you in making removal/remediation decisions. Some warning signs to look for include large dead or dying branches, damaged or decaying roots, and cracks or rot in the trunk (see photo)
Watch out for tree abuse
Trees that were seriously abused in the past by being topped or hat-racked or severely over lifted (see photos below) should be evaluated because they may be prone to breakage during high winds. Sometimes such trees can be remedially pruned; others may need to be removed.
Following topping or hat racking, sprouts that form on decaying branch stubs may develop into weakly attached limbs. Once they become long and weighty, such branches may break off during high wind events.
Poor pruning results in weak trees!
Over lifted trees with too much lower and interior canopy removed are commonplace. Note the barren branches have little taper and their ends may be tip weighted, increasing the likelihood that they may break. Don’t let a tree service do this to your trees!
2. Practice proper pruning and hire a professional tree service.
Just as with electrical, construction, plumbing and other work done on our homes, there are established industry guidelines and municipal codes for tree trimming that must be followed to ensure quality work and a safe outcome. Be sure that your tree service is fully licensed and insured. In Broward County, all businesses and sole proprietors doing such work must be operating with a current, valid Broward County Tree Trimming License. Ask to see their credentials, just as you would any other professional. Improper tree pruning can become a liability for you and your family.
3. Correcting structural defects in the canopy is key to improving wind tolerance.
We have learned that the most common cause of tree failure in storms is poor structure—multiple trunks (co-dominant leaders) that are weakly attached and have bark pinched inside their crotches (see photos below).
Codominant leaders (multiple trunks) are a structural defect that makes medium to large-maturing trees prone to splitting apart. This could have been prevented had the tree been structurally pruned earlier in its life.
Unfortunately, too many property owners only think about clearing low hanging limbs when hiring a tree service. If you are going to have your trees trimmed, be sure to work on resolving structural defects. Codominant leaders can usually be corrected with several rounds of structural pruning on young and middle-aged trees. Larger trees and older trees will take more time and more work.
Following several years of reduction pruning, the codominant leader on the right was completely removed.
Which tree do you think will survive the next storm? The tree on the left with numerous weakly attached codominant leaders, OR the tree on the right pruned to a single dominant trunk with well-spaced scaffold branches?
4. Don’t over prune your palms
Many people think that trimming most of the fronds off of a palm tree is the best way to prepare for a storm. Actually, the truth is quite the opposite! An abundance of palm fronds protects the bud or growing point of the tree which is located at the base of the palm tree’s canopy. Over pruning exposes the bud to storm-force winds which can fracture it or break it completely, killing the tree. The best practice is not to remove green fronds that originate above the horizontal, similar to the 9:00/3:00 position on an clock. Flowers, seed pods or fruit can be removed anywhere at any time.
Over pruned Sabal palms. Removing too many live green fronds can expose the bud causing damage or death during high wind events.
No guarantees, but….
Following these guidelines is no guarantee that your trees will come through future storms without any damage. However, best management practices will likely improve their chances for survival, reduce potential liability and decrease overall maintenance and replacement costs.
Co-authored by: Dr. Michael Orfanedes and Donna Corbelli Castro