Borers – Caterpillars

Order/Family: Lepidoptera/Aegeriiddae

Description:

  • Banded ash clearwing: Adults are 3/4-inch long clearwing moths. The abdomen and wings are metallic dark brown to black and their legs have yellow bands. Males have a yellow band around their abdomen.
  • Dogwood borer: Adults are clearwing moths, which are 3/8-inch long. The abdomen is bluish -black with two yellow bands. The cream colored larvae have dark heads and when mature are 1/2-inch long. They have five pairs of prolegs with two parallel rows of hooks on each.
  • Rhododendron borer: Adults are clearwing moths, which have a black abdomen with three yellow bands. They are 1/4-inch long. The larvae are 1/2-inch long, white with brown heads.
  • Leopard moth: Adults are large, reaching 1-1/2-inches long. They are white with black spots on the wings and thorax. The larvae are 2-inches long and are pale yellow with black spots on the body.

 

Biology and Habits:

  • Banded ash clearwing larvae overwinter in their galleries and continue development through out the summer. There is one generation per year.
  • Dogwood borers overwinter as larvae under the bark of trees.
  • The larvae bore and feed under the bark. Typically, trees that are attacked have been damaged by mowing or other mechanical injury. There is one generation per year.
  • Rhododendron borers tunnel through the branches where they mature and overwinter. There is one generation per year.
  • Leopard moth larvae bore in the trunks of trees and development requires two years. Larvae overwinter in the wood.

 

Turf Attacked:

  • Banded ash clearwing: ash.
  • Dogwood borer: dogwoods, apple, oak, hickory, cherry, ash, and hazel.
  • Rhododendron borer: rhododendron, azalea, and mountain laurel.
  • Leopard moth: apple, ash, beech, elm, maple, oak, poplar, plum, and willow.

 

Damage:

  • Banded ash clearwing: infested branches on mature trees typically die. Young trees may be killed by the infestation.
  • Dogwood borer: excessive tunneling causes the bark to crack. Mature trees may suffer dieback, whereas younger trees may die.
  • Rhododendron borer: tunneling may cause branches to split, exposing frass. Heavy infestations may girdle the branches causing wilting and dieback.
  • Leopard moth: typically dieback occurs when these larvae bore in branches and small caliper trees.