Hawthorn
Symptom Cause  
Leaves wrinkled; stunted; leaves fall off
Aphids
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Many holes in branches; limbs girdled sawdust at holes
Borers
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White, cottony, cushion-like mass on leaves, stems or branches
Cottony Cushion Scales
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Young portions of foliage disappear, or young tips disappear, bark peeled off
Deer
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Blossoms, leaves wilt, turn black, bark is water soaked
Fire Blight (bacterial)
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Leaves mottled yellow and green; hard, shiny droplets on underside of leaves
Hawthone Lacebug
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Trees defoliated, brown egg cases appear on trunk
Larvae of Gypsy Moth
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Leaves covered with white powder
Powdery Mildew
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Leaves have red, orange, yellow or brown spots
Rust (on plants)
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Black powdery sooty mold fungus forms on honeydew; branches may die
Sooty Mold
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White or gray waxy thread coverings
Wooly Aphids
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