Diagnosing Slime Flux and Borer Damage in Red Oak

A young red oak oozes white, foamy liquid from a trunk wound with heavy sap flow. The owner's older red oak died after similar symptoms. Drought conditions prevail in Texas.

Combined Diagnosis

Photos reveal both slime flux (bacterial wetwood) and borer activity. Drought stress weakened the tree, inviting borers to tunnel under bark. Their entry points allow slime flux—fermented sap pushed out by bacterial gas pressure—to escape.

Treatment Plan

• Borer control: Spray trunk with Merit or Onyx insecticide to kill larvae under bark.
• Drought relief: Water deeply—1 inch every 3 days for several weeks, then weekly.
• Slime flux management: No cure exists. Fertilize with 10-10-10 at 1 lb per inch trunk diameter to boost vigor. Wash trunk with bleach solution (1 pint chlorine per gallon water) to deter insects.

Monitor the older oak's fate—similar stress factors likely contributed to its decline. Prioritize tree health to resist future attacks.