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Maple Tree Cauliflower Fungus: Conk Indicates Internal Decay

Maple Tree

Maple has cauliflower-like growth; owner asks ID.

ID: Fungal Conk (Sporophore)

The structure is a fruiting body of a wood-decay fungus (likely Ganoderma, Fomes, or Laetiporus). It signals heartwood rot inside the trunk.

Implications

Decay is irreversible; cannot be cured.
Tree may stand years if vigorous (compartmentalization).
Watch for canopy deadwood increase.
If tree threatens people/property, removal is safest.

Plant Diseases: Managing Internal Decay in Mature Fruitless Mulberry Trees; Poplar Tree Decay: Irreversible Heart Rot and Structural Risk; Old Tree Trunk Damage with Decay: Not Deer, Likely Past Wound Leading to Structural Hazard; Maple Storm Damage: Internal Decay, Carpenter Ants, and Structural Risk; Bark Separation on Whitespire Birch: Internal Decay, Not Just Borers; Lion's Mane Fungus on Willow: Decay Fungus in Hollow Trunk; Tree Hole Repair: Don't Plug, Don't Seal, Let Nature Heal; Tree Stumps: Let Nature Decompose Them; Shagbark Hickory with Base Rot: Should You Remove It?; Detecting Hollow Trees: Resistograph and Increment Borer

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