Lightning-Strike Damage: Sawdust, Carpenter Ants, and Tree Safety

A large soft maple struck by lightning 4 years ago now shows sawdust-like material in the trunk center. Carpenter ants are present, but no termites. The tree is 10–12 ft from the house.

Assessment

• Sawdust (frass) indicates wood-boring insects (borers or carpenter ants) in dead heartwood.
• Heartwood is non-living—insects there don't kill the tree but can weaken structural integrity.
• Risk: A compromised trunk may fail in high winds, threatening the nearby house.

Action Plan

1. Have an arborist inspect for structural soundness—especially if the trunk is hollow or cracked.
2. Treat exposed wood with a borer-specific insecticide (ask your exterminator or nursery).
3. Monitor annually for worsening decay, lean, or canopy dieback.
4. Consider removal if the tree is a hazard target (house, drive, play area).

Lightning damage often shows up years later. Proactive assessment prevents surprises.