Each year, more than 350,000 to 400,000 lightning strikes are recorded in the UK. 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 felled due to structural degradation caused by the heat and mechanical forces generated by the electrical charge. What many people don’t realise 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 close to the structure and taller than the roof are most at risk to damage from side-flashes.
Bartlett Tree Experts offers lightning protection systems that can minimise the risk of damage from a strike. These systems use copper conductors connected to a ground rod to reduce tree damage and conduct the electrical charge to the earth where the energy is dispersed. They have an excellent record of protecting trees and they reduce the risk of a side-flash to adjacent structures. While lightning strikes are unpredictable and protection cannot be guaranteed, systems are effective and affordable when installed in accordance to industry standards.
Tall trees are obviously most susceptible to lightning strikes and certain species including Sequoiadendron, sequoia, poplar, cedar, and Douglas fir 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.