This willow tree is over 20 years old. The trunk is riddled with round holes and the leaves are curled and spotted. It appears to be under severe distress. Can this tree be saved? If not, can another tree be planted in the same location? We do not know exactly what kind of borers these are, but it would be impossible to address every hole with a pest eradication product. We need to know if the borers come from the soil or are air borne. Thank you for any help you can give us.