Oak, Live
Symptom Cause  
Swollen; sunken lesions on trunk
Bacterial Canker
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Lesions develop on twigs; leaves wilt/die
Blight (bacterial)
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Many holes in branches; limbs girdled sawdust at holes
Borers
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Holes in leaves
Caterpillars
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Young portions of foliage disappear, or young tips disappear, bark peeled off
Deer
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Foliage turns pale or mottled
Lacebugs
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Leaves consumed; tawny egg masses present
Larvae of Gypsy Moth
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Leaves blistered and curled up
Leaf Blister (fungus)
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Tip of leaves brown, internal larvae trails visible. Leaves skeletonized and rolled up
Leaf Miners
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Holes chewed in leaves
Loopers
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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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Leaves turn bronze; wilt; drop
Oak Wilt
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Tree underdeveloped
Planted too far north of its planting zone
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Leaves covered with white powder
Powdery Mildew
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Bark of trunk and roots gnawed
Rodent Injury
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Leaves and branches encrusted with small bumps
Scale Insects
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Mushrooms sprout at base of tree; roots covered with string-like growths
Shoestring Root Rot (fungus)
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Small twigs drop; or hang with dried leaves
Twig Pruner
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