Termites can be a headache to treat when they infest your home. But when termites invade a beloved old tree, they can be a nightmare. One of the standard treatments for termites in lumber is to poison them. But treating termites in live wood precludes the use of many poisons. Fortunately, some organizations are developing alternative methods to treat termites, such as Louisiana State University (LSU) in its attempt to save trees in the French Quarter from Formosan subterranean termites.
Examine a tree for signs that it is infested with termites. Termites do not prefer to travel in the open. Instead they will construct mud tubes to shelter them as they move. You will find these shelter tubes on the ground surrounding a tree and along the bark of infested trees.
Dig around the roots of trees with a hand trowel to uncover termites. If a tree is infested with termites, you will find them in the soil among the roots of trees.
Look for mud nest entrances, called swarm castles, among root pruning scars. Termites use swarm castles as launching points during their swarming season.
Dig a trench that is 6 inches deep and 6 inches wide around the base of the tree. Pour a termite control barrier chemical formulated for penetrating the soil, such as Termidor, into the trench and allow it to seep into the soil.
Pour Termidor into a chemical spray applicator such as the kind used for applying pesticide to fruit trees. Spray the Termidor over the trunk of the tree where you see mud tubes.
Drill injection holes into an infested tree so that termite galleries are exposed. Inject a termite-killing foam such as Premise into the termite galleries using an injector designed for this purpose. The foam will kill bugs and push them out of the tree.