Willow, Pussy
Symptom Cause  
Leaves curl/discolor; honeydew on undersides of leaves, sooty mold forms
Aphids
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Foliage looks bad, small cocoon-like silken bags hang from twigs
Bagworms
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Leaves wilted; discolored; die back
Blight (bacterial)
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Branches swollen and distorted; holes; sawdust and sap stains at base of trunk
Borers
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Leaves spotted; stems develop lesions
Canker (fungus)
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Holes in leaves
Caterpillars
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Tumor-like swellings on trunk or branches
Crown Gall
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Leaves consumed; conspicuous tawny egg masses present
Gypsy Moths
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Leaf undersides damaged
Imported Willow Leaf Beetle
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Foliage turns pale or mottled
Lacebugs
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Leaves wilt and turn brown
Midges
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Leaves covered with white powder
Powdery Mildew
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Leaves become distorted and cupped
Psyllids
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Yellowish spots/dark pustules on leaves
Rust (on plants)
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Leaves are skeletonized
Sawflies
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Leaves yellow, drop; bumps on leaves and stems; sometimes sticky leaves
Scale Insects
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Black powdery sooty mold fungus forms on honeydew;
Sooty Mold
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Leaves discolored and distorted.
Thrips
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Break in storms
Weak Wood
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Holes chewed from outside to middle of leaves; leaves look notched
Weevils
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