Brussels Sprout
Symptom Cause  
Small, yellow spots, old leaves; spots enlarge, black growth
Alternaria Leaf Spot
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Leaves turn yellow and are cupped downward
Aphids
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Holes in leaves; edges chewed
Cabbage Loopers
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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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Tiny, black hopping insect, numerous 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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Plants disappear all or in part
Rabbits
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Plants disappear all or in part
Woodchucks
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