The dogwood borer prefers flowering dogwood as its hosts. Infestations in young trees usually occur in the main trunk, often around lawn mower injuries.
Infestations in order trees are likely to be higher up in limb crotches or main limbs and associated with pruning scars, cankers, or cracked bark. Dogwood trees planted in the sun are more susceptible than trees in the shade. Symptoms include dieback of branches and coarse, sawdust-like frass expelled from cracks in the bark. This insect species is widely distributed wherever dogwoods are cultivated. Optimal spray timing based on calendar date is about the first week of June. Shade tree and landscape insecticides containing bifenthrin or permethrins as the active ingredient can be used for preventive control.
Avoid planting native understory species such as dogwoods and rhododendrons in full sun.
Plant hardy, well-adapted cultivars for your region. Maintain tree vigor through proper planting, balanced fertilization, and adequate irrigation during drought periods. Transplanted trees need extra water until they become established.
