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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Maple > Small holes in trunk

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Maple > Trunk/Branches > Small holes in trunk

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  • Image: Maple callus borer 1
  • Image: Maple callus borer 2
  • Image: Maple callus borer 3

Maple callus borer
Synanthedon acerni

  • 1/8 to 3/16 inch holes in stem near damaged bark or other wounds that may become disfigured and unattractive with high infestations
  • Pupae stick out of exit hole, empty pupal cases are commonly observed after moths have emerged
  • An adult moth, appearing wasp-like, has translucent wings with black markings; bluish-black antennae on a reddish-orange head and mid-section
  • Silver maple is preferred host
  • More information on Maple callus borer
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  • Image: Pigeon tremex 1
  • Image: Pigeon tremex 2
  • Image: Pigeon tremex 3

Pigeon tremex
Tremex columba

  • 5/16 inch round exit hole, clustered on trunk
  • Sometimes dead female insects remain stuck in stem
  • Adults are up to 2 inches long with a reddish brown, oblong body; females have a conspicuous ovipositor on the tip of their abdomen
  • More information on Pigeon tremex

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