When Lightning Strikes
Lightning strikes thousands of trees each year. There are several signs of possible lightning damage. Sometimes there is peeling bark or cracking. The ground around the tree may show signs of cracking, which follows the roots of the tree. The leaves may show signs of wilting or scorch. In severe cases, the entire tree may split down the middle or look as if it exploded.
If you suspect lightning damage, some common practices can be done to help save your trees. Remove any loose bark from the trunk and trim all jagged or loose edges. Unfortunately, little can be done for bark damage, but it is important to scout for potential insects on open wounds. It is not necessary to use pruning paints to cover wounds. Research proves that pruning paints do not benefit the healing process. During dry periods, make sure that the tree has adequate moisture. Water with a hose set at a slow flow for several hours. Check the soil every week and a half for moisture. For historic, rare, or specimen trees, a lightning protection system can be installed to prevent lightning damage. Contact an arborist for more information on lightning protection systems. Certified arborists can be found in your local telephone directory under “tree services.” When in doubt, call a professional to evaluate damage done to trees.
Certain types of trees are more likely to sustain lightning damage than others. Evergreens such as pines, spruce, hemlock and fir have high resin content. They conduct more electricity than trees with low resin and are more susceptible to explosion and internal heating. Trees with high starch content are also more susceptible to damage. Oak, maple, ash, poplar, and tulip trees are good conductors of electricity. Trees such as beech and birch are high in oil content. Oil is a poor conductor of electricity, making birch and beech less affected by lightning.
Related Information: All About Pruning, www.oznet.ksu.edu