August and September are the prime hurricane and tropical storm months in the U.S., particularly in the South. Hopefully, most of us won’t need to batten down any hatches this summer, but if we do, we need to pay attention to the trees on our properties. In a hurricane, one of our landscape’s greatest assets can become an inadvertent weapon of destruction.
A tree falling in your yard, on your house, or on power lines is one of the most dangerous consequences of any storm. The higher the wind speed, the greater the chance a tree will come down, but wind speed is only one factor. According to researchers at the University of Florida/Institute of Food and Agricultural Sciences, tree canopy density, the speed of the storm, the amount of rain and flooding or soil saturation, and the age and health of individual trees also influence whether a tree stands or falls.
While there are tips that will help your existing trees weather a storm, real hurricane preparedness happens in the landscape design stage, when choosing trees and deciding where to plant them. Some species resist wind better than others, notes the UF/IFAS study. Not surprisingly, many are natives. The list of wind-resistant trees (appropriate for the Southeastern coast and Florida) is long, and includes:
Baldcypress (Taxodium distichum)
Crape Myrtle (Lagerstroemia indica)
Date Palm (Phoenix dactylifera)
Dogwood (Cornus florida)
Live Oak (Quercus virginiana)
Podocarpus (Podocarpus spp.)
Sand Live Oak (Quercus geminata)
Southern Magnolia (Magnolia grandiflora)
Yaupon Holly (Ilex vomitoria)
A tall specimen tree planted by itself in a lawn is a prime candidate to tumble because it doesn’t have a web of roots from surrounding trees to grow into to stabilize it. Trees planted en masse protect each other, not only by their root systems, but also through their interweaving canopies. Clusters of at least five trees offer the most stability; varying the heights and species of trees offers more protection.
When you know a storm is coming, there are a few things you can do to prepare.
Remove existing dead or damaged limbs. They’ll be the first to go when the wind starts howling. Lightly thinning no more than a third of an overgrown canopy will keep air moving through a tree. The exception is certain palm trees, which become less stable if too much top growth is removed. Large or valuable trees can be braced with 2 x 4s and metal or nylon strapping.
After the storm, once it’s safe, take a look around and survey the damage to the landscape. Unless a tree has snapped in half or is otherwise too far gone, it may be possible to save it. As long as injured trees are not a hazard to people or property, be patient. Trees hit by wind and salt water may be defoliated and look dead at first – palms especially – but time and TLC can bring them back from the brink. Toppled trees can be pulled upright, reset in their holes, and the roots re-covered with soil. If it’s done promptly, they may survive.
And if a tree is a total loss? Plant another one – or more than one – ideally the native species that have evolved to handle the energy big storms can bring.