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Ash Tree Basal Decay: Irreversible Heartwood Rot on West Side

Ash tree shows orange-brown stain creeping up west side; bark now peeling, revealing soft dead wood. Other ash unaffected.

Diagnosis

Bark loss + soft wood = internal decay fungus (likely Perenniporia or Ganoderma). One-sided suggests a past wound (mower, lightning, root injury) on that side.

Prognosis

Decay is progressive and irreversible. Canopy will thin; structural failure risk rises. No fungicide penetrates heartwood.

Palliative Care

Fertilize and water to maximize vigor (compartmentalization).
Monitor for canopy dieback and fruiting conks.
Arborist risk assessment if near targets.

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