Forsythia
Symptom Cause  
Tumor-like swellings on trunk or stems
Crown Gall
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Sunken spots; brown spots on leaves
Fungal Diseases
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Base of stems; roots gnawed
Mice
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Leaves stippled, yellow, dirty; webbing on interior stems of plant
Mite
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Shrub branches root in soil
Natural Habit
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Tumor-like swellings on trunk or stems
Phomopsis Gall
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Base of stems; roots gnawed
Rabbits
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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 material on leaves
Scale
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Flowers and twigs shrivel
Twig Blight
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Base of stems; roots gnawed
Voles
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Holes chewed from outside to middle of leaves; leaves look notched
Weevils
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