This is true for two reasons.
Wood borer treatment in trees.
Adding mulch around your tree and providing it with supplemental water and fertilizer will help it fight off borers and heal from previous damage.
These trees must be removed for safety s sake.
Chemical control of borers.
Borer beetle treatment options the control of tree borer beetles is really not a control as much as it is a preventive treatment.
The damage from the tunnels alone can girdle and eventually kill the tree and the holes represent the perfect opening for opportunistic infections.
Borers are the immature stage of certain moths and beetles that dig their way through the living wood of a tree destroying tissues the tree needs to store water and transport sap.
Trees which have activity are difficult to save.
First once a tree is infested the adults and larva are active behind the bark which serves as protection from conventional sprays.
Use as directed for black vine weevil larvae bronze birch borer cottonwood longhorned borer flatheaded borers including alder and birch borer pine tip moth larvae and other listed pests.
Injection into trees more than 2 inches in diameter that will not produce food within a year after treatment.
Borers are beetle or moth larvae that develop under the bark of trees damaging the wood and eventually killing the tree.