Your extension corner: Heal your damaged trees
By Sallie Lee
Urban Regional Extension Agent
Question: What can I do to save storm-damaged trees? Several trees in my yard were victims of strong winds. I’d very much like to save them instead of cutting them down. However, some have their tops blown out or trunks broken about half way down. Any suggestions?
Answer: One of the first questions asked by tree owners after a storm is “Will my tree live?” Aside from damage to structures and vehicles, trees comprise one of the largest categories of post storm concern. If the tree is capable of causing new or additional damage to structures or life if it is not removed, it is generally classified as a “hazard tree,” and the recommendation is to have it taken down. However, there are several conditions for which removal is not necessary, or for which removal can be delayed for weeks or months with no adverse results.
Your first response to storm damage may be to get the mess cleaned up, including your landscape. But decisions made too quickly may result in getting rid of trees that could be saved, causing unnecessary expense for removal and replacement, and in some cases the emotional issues associated with sentimental or “family” trees.
Be aware that trees between the street and sidewalk are usually city-owned and therefore the city’s responsibility; if that tree you want to save isn’t technically yours and it interferes with removal of storm debris, it may not be salvageable regardless of your affection for it.
Storms result in different kinds of tree damage, and each one has its own particular impact on long-term tree health. The first and most severe damage results from a split or break in the central trunk. This usually occurs more often with older and larger trees, in which strength of the remaining trunk is immediately reduced. The second kind of damage is associated with bending, which is seen on younger trees i.e. sapling size. When the main stem or trunk is bent, the tree “sets” in that position; recovery to upright depends on how far the trunk bends and the length of time the tree remains in that position. The third and usually least damaging response is broken branches. Unless they involve over 75% of the crown, the tree’s future looks pretty good. If the breaks are left jagged and not pruned properly, it is possible that decay will develop in the broken stubs, but that process usually takes several years and doesn’t threaten trunk strength.
How can you help trees “heal?”
Resist the urge to over prune, or let anyone else do it for you. The “after” tree may not look the same as “before” the storm, but let the tree’s ability to heal itself take control – trees are amazingly resilient.
If possible and without injury to yourself, remove broken branches still attached to the tree. Done correctly, the risk of decaying agents entering the break will be minimized.
Repair torn bark by very carefully using a sharp chisel or knife to smooth ragged edges of wounds where bark was torn, trying not to expose any more of the cambium (greenish inner bark) than necessary.
And avoid topping your trees, or having them topped. Professional arborists (“tree people”) suggest that this practice of cutting main branches back to stubs is one of the least helpful practices inflicted on a tree. The stubs usually grow back as many weakly attached branches even more likely to break when the next storm hits. In addition, the tree will need all possible resources to recover from storm damage stress. Topping trees reduces the amount of foliage (those green leaves) the tree needs to provide it with food and nourishment. A topped tree, already stressed by storm damage, is more likely to decline and die than one that has not been topped.
For more information regarding storm-damaged trees, or to find out which trees have the highest level of wind resistance, please contact Sallie Lee, Urban Regional Extension Agent at the St. Clair County Extension office by calling (205) 338-9416 or email leesall@aces.edu.