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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Birch > Unusual growth on trunk

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Birch > Trunk/Branches > Unusual growth on trunk

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  • Image: Canker rot 1
  • Image: Canker rot 2
  • Image: Canker rot 3

Canker rot
(aka. sterile conk or cinder conk)
Inonotus obliquus

  • Rough, cracked black, knob or cone like fungal growths protrudes from trunk, often near an old wound or branch stub
  • Internally fungal growth is spongy, colored yellow-brown to
  • Infected trees often break at the point of the fungal growth
  • Mottled white and reddish brown wood decay can be seen within infected trunks
  • More information on Canker rot
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  • Image: Perennial nectria canker 1
  • Image: Perennial nectria canker 2
  • Image: Perennial nectria canker 3

Perennial nectria canker
Neonectria galligena

  • Sunken target shaped cankers on main trunk or branches
  • Cankers do not have bark and raised ridges of wood occur in target-like rings within the canker
  • Red to reddish orange raised cushion like bumps can occasionally be seen on the edge of the canker
  • Dead branches and twigs killed by girdling cankers
  • More information on Perennial nectria canker

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