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Tree with Black Scarring and Hollow Branches: Hypoxylon Canker

Tree shows black scarring to top, splitting/cracking bark, black moldy rings on dead cut branches, hollow black/ashy interior. Top slightly wilting, leaves unspotted.

Diagnosis: Hypoxylon Canker

Black fungal growth indicates Hypoxylon, a canker disease causing internal decay in hardwoods. Progressive, incurable. Tree will decline structurally over years, eventually becoming hazardous in storms.

Management

No cure exists. Monitor for increasing dead wood. Plan for eventual removal before failure risks property or people. Consult provided UAEX bulletin (FSA-7557) for details. Maintain vigor with water/fertilizer to slow progression.

Plant Diseases: Pecan Tree Black Nuts and Spider Webbing: Phytophthora Root Rot and Harmless Barklice; Tree Black Growth and Sap: Gummosis from Borers or Black Knot Disease; Black Knot Disease on Plum: Pruning and Fungicide Protocol; Black Oak Sudden Oak Death or Slime Flux in California Mountains; Mock Orange Annual Black Bugs and No Blooms: Atomic Grow Sucrose Boost for Defense; Sooty Mold on Large Trees: Systemic Imidacloprid for Aphid Control; Black Bark on Ornamental Pear: Possible Fungal Canker; Cherry Tree Black Canker: Professional Diagnosis Needed; Fir Tree Infestation: Aphids/Scale, Sooty Mold, and Systemic Treatment; Black Mold on Young Tree: Aphids and Sooty Mold Fix

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