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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Maple > Holes in leaves or parts of leaves missing

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Maple > Leaves > Holes in leaves or parts of leaves missing

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  • Image: Cankerworms 1
  • Image: Cankerworms 2
  • Image: Cankerworms 3

Cankerworms
Alsophila pometaria (fall) and Paleacrita vernata (spring)

  • Larvae chew between the major veins at first, eventually chewing everything except midveins
  • Defoliation typically light to moderate, although it can be severe
  • Smooth-bodied, light green to brown, 2 inches long when fully grown; moves in characteristic looping motion
  • Damage occurs late April/early May until June
  • More information on Cankerworms
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  • Image: Linden looper 1
  • Image: Linden looper 2
  • Image: Linden looper 3

Linden looper
Erannis tiliaria

  • Chews portions of leaves; defoliation typically is minor
  • Smooth-bodied with reddish brown head, it is patterned black, gray, yellow, with a light colored underside; moves in characteristic looping motion; 1 ½ inch long
  • Occurs May and June
  • More information on Linden looper
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  • Image: Whitemarked tussock moth 1
  • Image: Whitemarked tussock moth 2
  • Image: Whitemarked tussock moth 3

Whitemarked tussock moth
Orygia leucostigma

  • Young larvae windowpane feed (i.e. feed on one layer of leaf tissue between veins) giving them a lacelike appearance
  • Older larvae consume entire leaves except the midrib and large veins
  • Caterpillars have a red-orange head with two sets of black tufts near the head; yellowish hairy body with distinct tufts of hair resembling a toothbrush on top of the body
  • Full grown larvae are 1 ¼ inches long
  • Damage by 2 generations- first from May to June and a second one from August to September
  • More information on Whitemarked tussock moth
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  • Image: Greenstriped mapleworm 1
  • Image: Greenstriped mapleworm 2
  • Image: Greenstriped mapleworm 3

Greenstriped mapleworm
Dryocampa rubicunda

  • Defoliate trees by eating entire leaves, except the central vein
  • Mature larvae with red head, 7 lines running longitudinal down body that are light to dark green; 2 “horns” just behind the head
  • At maturity, 1.5 inches long
  • Feeding common late July and early August
  • More information on Greenstriped mapleworm

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