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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Crab Apple > Yellowing leaves

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Crab Apple > Leaves > Yellowing leaves

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  • Image: Iron Chlorosis

Iron Chlorosis

  • Newest leaves towards ends of branches are generally yellowed, while leaf veins remain green (interveinal chlorosis)
  • More common in western Minnesota
  • More information on Iron Chlorosis
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  • Image: Honeycrisp Leaf Mottle Disorder 1
  • Image: Honeycrisp Leaf Mottle Disorder 2

Honeycrisp Leaf Mottle Disorder
(Also known as Honeycrisp Chlorosis)

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  • Image: Powdery Mildew 1
  • Image: Powdery Mildew 2

Powdery Mildew
Podosphaera leucotricha

  • Part or all of infected leaves are covered in white-gray, felt-like patches
  • Infected leaves will curl, twist, or fold upward
  • Infected blossoms are distorted, discolored, and covered in white powdery fungal growth
  • Infected fruit have bronze, corky streaks, that are skin deep
  • More information on Powdery Mildew
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  • Image: Dogwood Borer 1
  • Image: Dogwood Borer 2
  • Image: Dogwood Borer 3

Dogwood Borer
Synanthedon scitula

  • Larvae feed in young trees often around lawn mower injuries, and in pruning scars of older trees
  • Feeding causes girdling and reduced sap flow
  • Brownish-red frass (excrement) is usually present at the feeding site
  • Adult is a black and yellow clear-wing moth, larvae are ½" long when mature, and white with a red-brown head
  • Adult emergence begins in mid-June, peaks in early July, and continues until August
  • More information on Dogwood Borer

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