Poplar, Lombardy
Symptom Cause  
Galls on leaf stems; end buds distorted
Aphids
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Swollen; sunken lesions on stems; trunk
Bacterial Canker
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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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Leaf tissue eaten between veins, circular holes; foliage turn brown, dry; twigs die
Imported Willow Leaf Beetle
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Leaves blistered and curled up
Leaf Blister (fungus)
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Brown spots on leaves; leaves fall prematurely
Leaf Spot
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Twigs break off
Poplar Curculio
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Leaves covered with white powder
Powdery Mildew
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Leaves; branches encrusted with bumps
Scale Insects
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Black powdery sooty mold fungus forms on honeydew; branches may die
Sooty Mold
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