Northern Tooth Fungus on Maple: White Polymer Mass from Heartwood Decay

Mature maple extruding white, hard, polymer-like mass with long fibers inside. Not wetwood/slime flux.

ID: Northern Tooth Fungus (Climacodon septentrionalis)

• White, soft, spongy heartwood rot in maples
• Enters via wounds, frost cracks, dead stubs
• Large, fleshy, shelf-like conks (Jul–Aug)
• Slow, irreversible, but tree lives years
• Advanced: crown dieback, wind failure risk
• Remove if annually fruiting + severe decay

Process cannot be reversed. Monitor structure.