Maple Tree Black Ooze: Slime Flux (Wetwood)—A Mixed Blessing

Bitter, black ooze from a maple in Alabama is slime flux—fermented sap from bacterial wetwood. Bacteria enter a wound, create conditions that inhibit decay fungi, then produce gas that forces liquid out.

What It Means

• Not a primary killer. Tree may live years.
• Sign of past injury (mower, trimmer, construction).
• Flux may discolor bark, kill grass/moss at base.

Management

• Avoid further stress. Water, mulch, fertilize if needed.
• Flush ooze with water or dilute bleach to reduce smell/insects.
• Call Alabama Forestry Commission for free forester visit: forestry.state.al.us

Silver Lining

Wetwood bacteria protect against worse decay organisms. It’s a natural defense gone visible.