Spirea
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
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Lower foliage looks burned
Dog Urine
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Leaves and twigs die back
Fireblight
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Holes in flowers; leaves rolled up
Leafrollers
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Leaves coated with white powder
Powdery Mildew
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Plant stunted, leaves yellowed, lesions on roots
Root Knot Nematodes
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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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