Each year, more than one million trees in the United States are struck by lightning. A lightning strike can immediately kill trees or weaken them so severely that they are then attacked and killed by boring insects or other secondary invaders. In some cases, lightning struck trees must be removed due to structural degradation caused by the heat and mechanical forces generated by the electrical charge. 

 

What many people don’t realize is that lightning not only poses a risk to trees, but to adjacent structures as well. Damage to structures can occur when lightning strikes a tree and then side-flashes (“jumps”) to more conductive materials such as downspouts and other metal objects. Houses with trees within ten feet of the structure and taller than the roof are most at risk to damage from side-flashes.

 

 

In fact, lightning rarely damages trees outfitted with a system that has been installed in accordance with ANSI-A300 Standards. While lightning strikes are unpredictable and protection cannot be guaranteed, systems are effective and affordable under these standards.

 

Tall trees are obviously most susceptible to lightning strikes and certain species including tulip tree, oak, pine, and maple are damaged more often than others. Historic trees, those in feature locations in the landscape, and those close to structures are also candidates for lightning protection.

 

Lightning protection systems should be inspected annually to ensure they are intact. Systems will require servicing to extend conductors and replace fasteners to accommodate growth of the trees in which they are installed.