Willow, Weeping
Symptom Cause  
Leaves curled and distorted; honeydew present on leaf
Aphid
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Leaves spotted; twigs and stems develop lesions
Bacterial Canker
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Leaves defoliated; foliage looks bad, small cocoon-like silken bags hang from twigs; twigs girdled
Bagworms
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Branches swollen and distorted; holes; sawdust and sap stains at base of trunk
Borers
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Edges of leaves eaten; 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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Foliage turns pale or mottled
Lacebugs
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Leaves consumed; conspicuous tawny egg masses present
Larvae of Gypsy Moth
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Leaves become distorted and cupped
Psyllids
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Leaves are skeletonized
Sawflies
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Leaves and branches encrusted with bumps
Scale Insects
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Leaves discolored in spots between veins
Thrips
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