Apple
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off, sooty mold can form.
Aphids
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Cream colored worms in fruit.
Apple Maggots
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Skin of fruit pierced or partially eaten.
Birds
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Many holes in trunk and branches: small limbs girdled, sawdust at holes
Borers
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Skeletonized leaves
Cankerworms
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Orange or brown pustules on leaves.
Cedar Apple Rust
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The ends of twigs die and fall off.
Cicadas
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Holes in fruit; sawdust around hole; interior of fruit dark, rotted.
Codling Moths
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Foliage and fruit disappears below ten feet.
Deer
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Leaves and twigs webbed together.
Fall Webworms
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Blossoms turn brown and die. Young twig tips brown, wilt, curl and die.
Fireblight
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Small misshapen fruits.
Flies, Fruit
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Trees defoliated, brown egg cases appear on trunk.
Gypsy Moths
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Beetle with a green head and copper colored back, holes eaten in flowers and or leaves.
Japanese Beetles
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Tip of leaves brown, internal larvae trails visible. Leaves skeletonized/ rolled up.
Leaf Miners
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Whitish to yellowish stippling of the leaves.
Leafhoppers
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Leaves rolled, and tied with webbing.
Leafrollers
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Cottony white masses on roots, stems, branches, leaves; reduced plant vigor.
Mealybugs
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Bark chewed near soil surface
Mice
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Crescent shaped cuts in the skin of the fruit. Fruit falls prematuraly.
Plum Curculio
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White dusty film on the leaves.
Powdery Mildew
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Leaves yellowed and may drop.
Psyllids
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Bark on young trees and shrubs may be stripped, girdling the plants.
Rabbits
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Stunted growth with fewer blooms and fruit, overall weakened plant.
Sawflies
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Olive-green spots or blotches appear first, then look velvety and finally turn to dark, scabby marks on fruit and leaves.
Scab, Apple
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Leaves/canes encrusted with small bumps, shiny and sticky leaves due to honeydew
Scale Insects
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Aphids, scale or other sucking insects secretes honeydew on which black powdery sooty mold forms.
Sooty Mold
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Leaves stippled, and yellow with webbing on interior stems
Spider Mites
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Fruit missing and bites taken out of fruit.
Squirrels
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Sunken brown spots, or dimples on fruit.
Stinkbugs
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Deformed flowers and dimples on fruit.
Tarnish Plant Bugs
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Hairy caterpillars weave large silken nests and skeltonize the leaves.
Tent Caterpillars
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Much foliage is eaten starting from top of tree down
Tussock Moths
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Bark chewed near soil surface
Voles
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