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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Hickory > Cracks or sunken areas of trunk or branches

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Hickory > Trunk/Branches > Cracks or sunken areas of trunk or branches

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  • Hickory decline 1
  • Hickory decline 2
  • Hickory decline 3

Hickory decline
Ceratocystis smalleyi and Scolytus quadrispinosus

  • Leaves are wilted or undersized, thin canopy with dead branches
  • When bark is peeled back, numerous reddish brown oval cankers up to 1 ft. long can be seen
  • Bark surface often shows no symptoms, occasionally cracking or dark sunken area can be seen
  • Dark bleeding spots that appear in May or June indicate cankers below the bark
  • Groups of young green shoots (sprouts) often form along the trunk; these wilt and die within a year
  • Round 1/8th inch exit holes of hickory bark beetles on upper trunk
  • Larval galleries often visible in discolored sapwood
  • Trees can decline and die in as little as two years when beetle populations are high
  • More information on Hickory decline
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  • Flatheaded appletree borer 1
  • Flatheaded appletree borer 2
  • Flatheaded appletree borer 3

Flatheaded appletree borer
Chrysobothris femorata

  • White froth usually oozes from cracks in bark
  • Dead branches in crown of older trees
  • Bark becomes sunken at site of injury; bark may crack later
  • Injured areas become larger and deform with annual attacks
  • Young and stressed trees are most at risk
  • Larvae are cream-colored, flattened bodies, about 1 inch long
  • Long tunnels under the bark girdle trees and cause structural weakness
  • More information on Flatheaded appletree borer
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  • Coral spot canker 1
  • Coral spot canker 2
  • Coral spot canker 3

Coral spot canker
Nectria cinnabarina

  • Sunken dark brown area on branch that is often cracked or has a ridge at the edge
  • Raised cushion-like bumps on affected branches, may be cream to orange or red, turn black with age
  • Dead branches and twigs, often first observed in early spring
  • Common on trees stressed by drought, recent transplant or other factors
  • More information on Coral spot canker
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  • Perennial nectria canker 1
  • Perennial nectria canker 2
  • Perennial nectria canker 3

Perennial nectria canker
Neonectria ditissima

  • Early canker symptoms are small and difficult to see, usually a darkened, depressed area forms on smooth, young bark
  • Sunken round to oval cankers with target shaped ridges of barkless wood on large branches or main trunk
  • Small dark sunken areas on twigs that can girdle or 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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