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Oak Trunk Sunken Area: Old Injury Compartmentalization, Not Active Disease

The 10"x10" sunken, blackened area at the oak's base is compartmentalized decay from an old injury (mower, vehicle, hammer—years ago). The tree walled it off chemically.

Do Not Treat

Poultices, sealants, or fillers trap moisture and invite pests. The tree is managing this internally.

Supportive Care

Occasional borer spray on the dark area
Deep weekly summer watering
Arborist evaluation if structural concern exists

The tree will slowly grow callus over the wound. Patience and basic care are the best medicine.

About Gardening: Oak Tree Weeping Sap: Borer Infestation and Treatment; Assessing Oak Trunk Decay: When to Worry About Heart Rot; Oak Trunk Rot: After Removing Soft Wood, Now What?; Large Basal Rot in Oak: Structural Risk and Next Steps; Sapsucker Damage on Ornamental Pear: Identification and Response; Oak Tree Cavity Assessment: When Holes Indicate Hazard; Decay Fungus on Shumard Oak: What the Mushroom Means; Mushrooms on Oak Trunk: Sign of Irreversible Internal Decay Requiring Removal; Large Oak Trunk Gall (Crown Gall) May Not Kill Tree for Years; Best Vine for a Dead Oak Trunk: Crossvine Over English Ivy

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