Turnip
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
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Young plant yellows, browns, dies; lower leaves wilt, die
Black Rot
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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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Young plant severed at soil
Cutworms
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White powder on leaf undersides; foliage wilts
Downy Mildew
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Tiny, black hopping insect, holes in foliage
Flea Beetles
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Tan, bleached spots, distortion on plants; flowers, fruit, drop
Harlequin Bugs
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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, internal larvae trails visible. Leaves skeletonized and rolled up
Leaf Miners
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Leaves stippled, yellowing or bronze; dry out and drop may be webbing visible; sometimes galls form on leaves
Mite
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