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

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Willow > Trunk/Branches > Cracks in bark or sunken areas of trunk or branches

1 of 3
  • Sapwood rot 1
  • Sapwood rot 2
  • Sapwood rot 3

Sapwood rot
Schizophyllum commune, Cerenna unicolor, Trametes versicolor

  • Dead branches within the canopy
  • Yellowing to brown leaves may be present
  • Groups or rows of small (
  • Schizophyllum shelf fungi are white and appear fuzzy on top
  • Cerrena fungi are white to greenish grey and have concentric rings on the surface
  • Trametes shelf fungi are tan to brown with darker rings
  • Wood below fungal shelves is yellowish to white, spongy, crumbly and decayed
  • Bark around fungal shelves is killed and often falls off
  • Common on trees stressed by drought, winter injury, wounds, mechanical injury or other factors
  • More information on Sapwood rot...
2 of 3
  • Valsa canker 1
  • Valsa canker 2
  • Valsa canker 3

Valsa canker
Valsa sordida

  • Leaves on random branches wilt, turn yellow then brown
  • Random dead branches seen throughout the canopy
  • Sunken irregulary-elongated cankers with cracked bark at the edges occur on branches or the main trunk
  • On thick barked trees, cankers may not be visible
  • In wet weather curled tendrils of orange spores emerge from pimple-like fungal structures within infected branches
  • Common on trees stressed by drought, winter injury, wounds, insect feeding or other factors
  • More information on Valsa canker...
3 of 3
  • Poplar and willow borer 1
  • Poplar and willow borer 2
  • Poplar and willow borer 3

Poplar and willow borer
Cryptorhynchus lapathi

  • Frass pushed out of openings in wood
  • Sap seeps from openings
  • Trunks become crooked and misshapen
  • Random shoots sprout along deformity
  • Damage most common on willow and poplar (except for quaking aspen), particularly young trees 1"- 4" diameter
  • Larvae are C-shaped, cream-colored and approx. ¼ inch long
  • More information on Poplar and willow borer...

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