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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Lettuce and Endive > Spots or blotches on leaves

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Lettuce and Endive > Leaves > Spots or blotches on leaves

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  • Image: Codling moth 1
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Septoria Leaf Spot
Septoria lactucae

  • Leaves have small, irregular-shaped yellow to brown spots
  • Tiny black dots can be seen in center of spots with a hand lens
  • Lower leaves are often infected first
  • More information on Septoria Leaf Spot
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  • Image: Plum Curculio 1
  • Image: Plum Curculio 2
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Flea Beetles
Disonycha xanthomelas, Systena blanda, and Phyllotreta spp.

  • Adult feeding on leaves creates shallow pits and small, irregular holes giving it a "shot hole" appearance
  • Heavy feeding may cause wilting
  • Adults are small (1/16 to 1/8 inch long), and vary in color from black, bronze, bluish, or brown to metallic gray, while some species have stripes
  • Present throughout the growing season
  • More information on Flea Beetles
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  • Image: Forest Tent Caterpillar 1
  • Image: Forest Tent Caterpillar 2
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Downy mildew
Bremia lactucae

  • Yellow to brown sunken angular leaf spots which are often restricted by leaf veins
  • Leaf tissue around the spots turns yellow
  • Fuzzy white growth can be seen on the underside of the leaves
  • Infected leaves often rot from secondary fungi and bacteria
  • Older outer leaves most commonly affected
  • Common in cool wet weather
  • More information on Downy mildew
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  • Image: White Rot 1
  • Image: White Rot 2
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Bacterial Leaf Spot
Xanthomonas campestris pv. Vitians

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  • Image: Yellownecked Caterpillar 1

Microdochium panattonianum

  • Somewhat circular dry brown leaf spots
  • Sunken oval dark lesions form on midrib and larger leaf veins
  • Center of leaf spot turns white and falls out, leaves appear 'shot hole'
  • In severe cases outer leaves wilt
  • More information on Anthracnose

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