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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Maple > Distorted or malformed leaves

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Maple > Leaves > Distorted or malformed leaves

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  • Image: Anthracnose 1
  • Image: Anthracnose 2
  • Image: Anthracnose 3

Discula campestris, D. umbrinella, Aureobasidium
apocryptum, Colletotrichum gloeosporioides

  • Young leaves turn brown to black, shriveled or curled
  • Mature leaves have irregularly shaped tan, brown or black leaf spots found along leaf veins; may be curled if severely infected
  • Lower, interior branches are most affected
  • Damage occurs in wet weather in early spring as leaves are expanding
  • More information on Anthracnose
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  • Image: Woolly alder aphid 1
  • Image: Woolly alder aphid 2

Woolly alder aphid
Paraprociphilus tessellatus

  • Insect feeding causes the leaf to fold in on itself
  • White woolly masses that look like threads are produced on leaves and twigs of its host
  • Excrete honeydew, a sticky, shiny material, on leaves and branches; sooty mold may also occur on honeydew
  • 1/8 inch, pear shaped insect inside white woolly mass
  • Silver maples are preferred hosts
  • More information on Woolly alder aphid

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