Lion's Mane Fungus on Willow: Decay Fungus in Hollow Trunk

Identification

Large, white, cauliflower-like then slimy growth emitting brown powder = Hericium erinaceus (Lion’s Mane, Bearded Tooth). A wood-decay fungus fruiting on a wound/hollow.

Implications

• Fungus decays heartwood; tree becomes hollow over years.
• Cement filling does not stop decay; may loosen as tree grows.
• No treatment to remove internal decay.

Management

• Fertilize with 10-10-10 (1 lb per inch trunk diameter) to boost vigor.
• Monitor for limb breakage as decay progresses.
• Some consider the fungus edible (caution: expert ID required).

30-year-old willow is nearing end of lifespan; enjoy while safe.