Borer Infestation in a Mature Pine: Treatment and Wound Management

A golf-ball-sized hole with recurring sawdust at the base of a large pine near Atlantic City indicates wood-boring insect activity, likely a borer species.

Why Household Sprays Fail

Common insecticides don't penetrate woody tissue where borers feed. The sawdust (frass) reappears because larvae remain protected inside.

Effective Treatment

• Use systemic insecticides: Merit (imidacloprid) or Onyx (bifenthrin)
• Apply around and into the hole
• These translocate in vascular tissue, killing feeding larvae

Don't Seal the Hole

Expanding foam or sealants trap moisture and slow the tree's natural compartmentalization. Pines produce resin that naturally seals wounds and inhibits decay fungi. Let the tree heal itself.

Long-Term Outlook

Borers rarely kill healthy pines outright. The greater risk is secondary decay fungi entering over many years, potentially creating hollows. However, pine resin production strongly inhibits this. Monitor for increased dieback or structural weakness, but immediate tree death is unlikely.