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White Oak Sudden Browning: Herbicide, Lightning, or Drought?

200-year-old white oak in Northern VA turned 85% brown in 8 weeks. Dry weather. Nearby oak healthy. No regrading. Owner asks if lightning or lawn herbicide could cause such rapid decline.

Possible Causes

Lawn herbicide (weed-and-feed): Root uptake causes foliar dieback.
Lightning: Usually leaves trunk scar; ground strike may show strike point.
Drought: Alone rarely this fast on a mature oak.

Action

Call VA Department of Forestry for a free forester visit to diagnose on-site.

County contacts: dof.virginia.gov

Do not guess—professional evaluation needed for a tree this valuable.

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