Cabbage
Symptom Cause  
Leaves turn yellow and are cupped downward
Aphids
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Leaves, stems and buds eaten
Armyworms
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Ash gray spots speckled with tiny black spots on leaves and stems. Stems become girdled, wilt and die. Moist conditions favor this disease.
Black Leg
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Holes in leaves
Cabbage Loopers
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Young plant wilts, turn yellow die; maggots feeding on roots
Cabbage Maggots
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Small holes in leaves
Caterpillars
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Seedlings cut off at base
Cutworms
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Plants disappear all or in part
Deer
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Small holes on older leaves; growing tip chewed out on young plants causing stunting; small caterpillars wiggle frantically when disturbed. Body wide in middle tapered at both ends.
Diamondback Moth Caterpillar
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Gray patches on lower leaves spread upward
Downy Mildew
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Little tiny holes in leaves
Flea Beetles
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White butterflies; ragged holes in leaves, bit of green excrement on leaves
Imported Cabbageworms
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Tip of leaves brown, larvae trails visible
Leaf Miners
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Leaves mottled yellow and green, raised dark areas; plant stunted
Mosaic Viruses
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Plants stunted, yellow
Nematodes
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Leaves coated with white powdery substance
Powdery Mildew
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Plants disappear all or in part
Rabbits
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Leaves notched; roots chewed
Root Weevils
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Ragged holes in leaves, often in middle
Slugs
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Water-soaked area on stem near soil; extends upward;
Watery Soft Rot
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Plants disappear all or in part
Woodchucks
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