Cotoneaster, Willow Leaf
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphid
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Leaves are spotted
Canker (fungus)
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Webbing holds leaves and twigs together
Cotoneaster Webworm
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Lower foliage looks burned
Dog Urine
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Spots on leaves; twig dieback and blackening
Fireblight
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Foliage turns pale or mottled
Hawthone Lacebug
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Bark of stems and roots gnawed
Mice
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Red to brown blister underside leaves
Pear Leaf Blister Mites
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Bark of stems and roots gnawed
Rabbits
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Leaves yellow, drop; bumps on leaves and stems; sometimes sticky leaves
Scale
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Black powdery sooty mold fungus forms on honeydew;
Sooty Mold
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Leaves stippled, yellow, dirty; webbing on interior stems of plant
Spider Mites
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Bark of stems and roots gnawed
Voles
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