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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Tomato > Hollowed out stems

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Tomato > Stem > Hollowed out stems

1 of 2
  • Image: Stalk Borers 1
  • Image: Stalk Borers 2

Stalk Borers

  • Damage occurs June to early August
  • Leaves wilt
  • Entrance hole where the caterpillar bores into the stem near ground level
  • Caterpillar can sometimes be found in stem
  • 3/4 to 2 inches long
  • Reddish brown head, brownish purple body with whitish stripes
  • More information on Stalkborers
2 of 2
  • Image: White Mold 1
  • Image: White Mold 2
  • Image: White Mold 3

White Mold
Sclerotinia sclerotiorum

  • Dark, firm water-soaked lesion on stem
  • Girdled stems die and turn bone white
  • Inside dead stems are black mouse poop shaped sclerotia
  • Fruit are soft and rotted
  • Cottony white mycelia inside and outside infected stems when humidity is high
  • Favored by cool humid conditions
  • More information on White Mold

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