Trees: Storms and Urban Trees
Strong storms, including hurricanes, tornadoes, and thunderstorms, are a common and recurring part of life in the Tampa Bay region. These storms influence the way we organize our personal lives, and how we design our homes, and manage risk. Trees and forests have been the predominant form of vegetation in the region for as long as people can remember. They have adapted, and survived the extremes of draught and soil saturation, very high lightning frequency, and strong winds. While trees declined and died, and eventually fell they did not threaten human life or property.
What is new in Florida are our homes, businesses, and public utilities. Today the loss of large limbs, or the failure of an entire tree may pose a risk to our well-being. How to recognize trees that may pose a risk to life and property, and how to prevent trees from becoming hazardous, is important for all of us to understand.
Resources and strategies to help prevent damage are listed near the bottom of the page.
Also important is to have an understanding of how to deal with your trees following a strong storm. Are they damaged? Which ones can be saved? Which ones need to be removed? How to have the work done, and by whom? Deciding which species of trees to use to replace the lost trees, how and where they should be planted?
What we learned from recent hurricanes and tropical storms
(from Edward F. Gilman, associate professor, Environmental Horticulture Department, UF/IFAS)
These are some of the lessons we learned from the recent hurricanes that struck the southeastern US. All photos were taken in Florida following hurricanes Charley and Frances.
- Trees that are preventively pruned are less likely to fail than neglected trees.
- Apparently healthy trees can blow down because supportive roots have decayed or soil becomes soft from saturation.
- Trees with one dominant trunk fair better than trees with codominant stems.
- Trees with bark inclusions are prone to falling apart.
- Large trees blow over; recently planted trees blow over; well established young trees are less likely to blow over.
- Construction activities within about 20 feet of the trunk of existing trees can cause the tree to blow over more than a decade later.
- Trees in shallow soils are more prone to blow over than trees rooted more deeply.
- Laurel oaks are prone to failure in hurricanes.
- Large pruning cuts create decay and cracks that can lead to breakage in storms.
- Trees become unstable in soils saturated by lots of rain
- Trees blow down in the prevailing wind direction.
- Root defects such as girdling roots cause trees to blow over.
- Uprooted trees can break underground utility lines such as water and sewer.
- Queen palms are prone to falling over; cabbage and Phoenix palms are able to stand firm in hurricanes.
- Trees in a group blow down less frequently than single trees. More information
- Tree trunks can be hollow without openings in the lower trunk; these are prone to failure in storms.
- Trees growing in confined soil spaces are prone to blowing over.
- Certain species appear more resistant to damage.
- Certain species appear more susceptible to damage.
Please also see our Preventing Tree Hazards page.