A lightning strike to a tree in your landscaping can be terrifying to witness, but it isn't always fatal to the tree. A tree may survive if there is no extensive burning and the tree remains upright. If you hope to save the tree, keep in mind that it can take a full growing season to determine whether a tree will survive or require removal.
Lightning strike damage isn't always immediately obvious. Sometimes a tree will alight from the strike, while in other cases the only visible damage may be a slash in the bark. The full extent of the wound may not be visible, but there may be extensive scorching and other damage on the interior of the trunk. If the visible wound is only on one side of the trunk, then the tree may survive.
A tree is less likely to survive if there are wounds on both sides of the trunk, as this means the lightning went through the heart wood and there is likely extensive internal damage. The tree is also less likely to make it if a major proportion of the crown is destroyed. Removal as soon as possible is usually the best option in these cases.
For those trees with a chance for survival, proper care is a must in order to provide a fighting chance. Begin with damage and hazard mitigation. Your tree service can remove any badly damaged branches so they don't pose a fall hazard. They will also tend to any wounds left behind by the lightning strike so that they can heal cleanly.
Water the tree regularly, particularly in dry weather, even if you usually don't provide extra water for your trees. A tree healing from a lightning strike won't be able to handle drought well. A fertilizer treatment is also a good idea.
It can take a year for the extent of the damage to become fully apparent, as some symptoms of severe decline may not appear until the first spring following the lightning strike. Winter dieback among the branches and poor budding and leafing out are symptoms of internal damage to the tree that it may not recover from.
In some cases, only half the tree will die back due to lightning damage. This is a danger as the uneven growth, even after pruning out the deadwood, can make a tree more prone to leaning and eventually blowing down. Minor dieback can be pruned out, but it's usually best to remove the tree if the dieback is extensive.
Contact a tree removal service for more information.