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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Hickory > Fungi growing on trunk or branches

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Hickory > Trunk/Branches > Fungi growing on trunk or branches

1 of 3
  • Ganoderma root and butt rot 1
  • Ganoderma root and butt rot 2
  • Ganoderma root and butt rot 3

Ganoderma root and butt rot
Ganoderma spp.

  • Leaves are small and may yellow and drop
  • Canopy appears thin with few leaves and multiple dead branches
  • Fungal conks, semicircle shelf fungi, can be found from the base of the tree up to 3 feet high on the trunk
  • Conks are reddish brown and shiny on top, white and porous underneath, a rim of white may be visible on the edge of the growing conks
  • Infected wood at the base of the tree is white, soft, stringy or spongy
  • Infected trees frequently break or fall over in storms
  • More information on Ganoderma root and butt rot
2 of 3
  • Armillaria root rot 1
  • Armillaria root rot 2
  • Armillaria root rot 3

Armillaria root rot
Armillaria spp.

  • Infected trees have poor growth, dead branches in the upper canopy, undersized and/or yellow leaves
  • Flat white sheets of fungal growth (mycelial fans) between the bark and sapwood at the base of infected trees
  • Thick black, shoestring-like fungus can sometimes be seen under the bark, around roots and in the soil around the base of the tree
  • Wood is decayed, white, soft and spongy; this may extend from the base of the tree well up into the trunk
  • Trees frequently break or fall over in storms
  • Clusters of honey-colored mushrooms may grow at the base of the tree in fall
  • More information on Armillaria root rot
3 of 3
  • Heart rot 1
  • Heart rot 2
  • Heart rot 3

Heart rot
Fomes fomentarius

  • Canopy may show no symptoms, or may have small, yellowing leaves or dead branches depending on the extent of decay
  • In cross section, the wood at the center of the trunk is white, mottled, soft and crumbly
  • Hoof-shaped, silvery-grey to brown, fungal fruiting bodies up to 8 inches across arise along the stem; often near a pruning wound, crack or other wound
  • More information on heart rot

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