Lightning can potentially kill a tree

With the recent heavy thunderstorm activity, the Gwinnett County Extension office has received many calls regarding trees struck by lightning. The callers want to know whether or not the trees will survive the strike. Lightning strikes have the potential to seriously harm and even kill a tree. Sometimes the tree can be saved, but often the injured trees will perish.

Lightning injuries are variable. The amount of damage will depend on the intensity of the lightning, the level of water present in the bark and the growth characteristics of the branches and trunk. The intense heat of the lightning will cause the liquids inside the tree to turn to gas leading to high pressure to build up inside the tree, causing it to sometimes be blown apart, stripped of its bark or set on fire.

Internal tissue could be burned and is not visible on the outside, and even the roots can be killed. Tall trees, especially those growing alone in open spaces or even amongst other, smaller trees, are most likely to be struck. Anyone standing under or near the trees could be killed by the lightning strike.

What happens when a tree on your property has been hit by lightning? The injured tree will be severely stressed as a result of the lightning strike. Some trees die rather quickly while others may take months or years to die, or may recover. The tree should be inspected carefully to ascertain the damage. The best course of action is to have a certified arborist or tree care company evaluate the tree and assess the level of damage as to whether or not the tree can be saved.

For recommendations for arborists, go to the Georgia Arborist Association web site at www.georgiaarborist.org. Immediate repairs are usually limited to cleaning up and cutting off damaged bark, and removing branches that may pose a danger. The tree will require additional amounts of water and nutrients to be applied for it to have a chance to survive.

Lightning can seriously injure or kill trees. Many factors come into play whether or not the tree will survive. Consultation with professionals is very important in assessing the survivability of the tree and whether or not any mitigating actions to improve its chances of surviving are warranted.

Timothy Daly is an Agricultural and Natural Resource Agent with Gwinnett County Extension. He can be contacted at 678-377-4010 or tdaly@uga.edu.