We live in a coastal town in the Pacific Northwest. In our garden, we have two Hollywood Junipers, separated by about 50 feet. In one only, there's evidence that the trunk is being bored into, causing dying off of the lower branches and gradually working its way upward. Have sprayed with Orthenex and also soaked the ground immediately surrounding the base. Have lost almost two layers of lower branches and am unsure if I'm using the right treatment. Can someone offer help?