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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Maple > Bark chewed or removed

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Maple > Trunk/Branches > Bark chewed or removed

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  • Image: Rabbit feeding 1
  • Image: Rabbit feeding 2

Rabbit feeding

  • Bark from young trees only is completely removed from the main trunk
  • Regular scraping the size of a spoon tip can be seen in the wood
  • Small twigs are cleanly cut off with a sharp edge, at a 45 degree angle
  • Damage can occur from ground level to several feet up the trunk depending on the depth of winter snow
  • Majority of damage occurs in winter and early spring
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  • Image: Vole feeding 1
  • Image: Vole feeding 2
  • Image: Vole feeding 3

Vole feeding

  • On young trees, bark is completely removed from the main trunk in irregular patches
  • Scraping the size of a fork tine can be seen in exposed wood
  • Damage occurs during winter from the ground level up to winter snow depth
  • Trees and shrubs appear to “die suddenly” during the growing season, especially if they experience any drought stress
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  • Image: Deer rubbing on young trees 1
  • Image: Deer rubbing on young trees 2
  • Image: Deer rubbing on young trees 3

Deer rubbing on young trees

  • Long lines of shredded or peeled off bark along main trunk up to 3 feet off the ground from antler rubbing.
  • Wood may appear shiny or "polished"
  • Leaves and small branches (>1 inch in diameter) cut off with a rough or ragged edge (Not a clean cut!)
  • Feeding occurs from the ground up to 6 feet or slightly higher. Ragged edges, same as above, also if the bark is removed by a deer there will be no sign of teeth marks
  • Damage is common only on young trees, old trees have thick bark and wide stem so are not used by deer for antler rubbing
  • More information on Problems with deer
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  • Image: Eutypella canker 1
  • Image: Eutypella canker 2
  • Image: Eutypella canker 3

Eutypella canker
Eutypella parasitica

  • As cankers age, the flattened surface turns black and bark begins to fall off revealing decaying wood in a target shape pattern below
  • Young cankers appear as round flattened, bark covered areas on main trunk or larger branch
  • Branch stub or other wound is often visible at center of the canker
  • White to buff-colored fungal growth may be seen around outer portions of expanding canker if bark is removed
  • Old cankers may develop a thick ring of wound wood surrounding the canker, making that area wider than the trunk above or below
  • Occurs on all maples but common on sugar maples in forest settings and Norway maples in urban settings
  • More information on Eutypella canker
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  • Image: Perennial nectria canker 1
  • Image: Perennial nectria canker 2

Perennial nectria canker
Neonectria ditissima

  • Sunken round to oval cankers with target shaped ridges of barkless wood on large branches or the main trunk
  • Small dark sunken area on twigs that can girdle and kill the branch
  • Red to reddish orange raised cushion like bumps can occasionally be seen on the edge of the canker
  • More information on Perennial nectria canker
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  • Image: Sapwood rot 1
  • Image: Sapwood rot 2
  • Image: Sapwood rot 3

Sapwood rot
Schizophyllum commune and Cerrena unicolor

  • Wood below fungal shelves is yellowish to white, crumbly and decayed; bark around fungal shelves is killed and often falls off
  • Dead branches within the canopy
  • Groups or rows of small (<2 inches wide) semi-circle self fungi along killed branches or on the main trunk
  • Schizophyllum shelf fungi are white and appear fuzzy on top
  • Cerrena shelf fungi are white to greenish grey and have concentric rings on the surface
  • Occurs on trees with an open wound or crack

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