Lightning Injury

Overview

Each year lightning strikes North America an estimated 25-100 million times. Occasionally, trees are struck, but of these twenty percent may not show any visible injury and damage may be minor. In other cases, trees can be destroyed as the electricity from the lightning vaporizes water in the tree trunk which then expands and splits the tree open. In other cases, damage may be slight to moderate with only a strip of bark being "blasted off" one side of the tree, usually from top to bottom.

Assessing overall damage to a tree and its prognosis for recovery can be difficult. In some cases, severe damage is evident and removal of the tree is obviously required, but in other cases, the full extent of the damage may not become apparent until weeks, months, or even years later.

Integrated Pest Management Strategies

1. Tree removal. If damage is extensive it may be obvious that the whole tree needs to be removed. In other cases, if there is still some hope to save the tree, removal of only any dangerous branches or parts of the tree may be required now to ensure the safety of people and property.

2. Wait and see. Since the full extent of the damage may not be apparent for some weeks or months, the homeowner may want to wait and see how the tree responds after any dangerous parts have been removed. In cases where just a narrow strip of bark has been blown off on one side of the tree healing can still occur and the recovery of the tree may be good. Any loose bark should be removed cleanly to facilitate healing and limit locations for disease and insects to take hold. In other cases, visual damage may initially appear slight but over time extensive damage becomes evident necessitating removal of the tree.

Organic Strategies

Both of the recommended IPM strategies are strictly organic approaches.