Snapdragon
Symptom Cause  
Flowers yellow-green; deformed; shoots spindly
Aster Yellows
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Plant stems rot at soil line
Damping-Off
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Plant actually disappears
Deer
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Green plant colors, wilts, tans; pink mass on roots; plant dies
Fusarium Wilt
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Brown spots on leaves, grayish mold forms on tissue, gray mold on flowers, leaves, stems soft, rotted
Gray Mold (Botrytis Blight)
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Leaves and flower buds deformed
Mite
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White powder coats top of leaves
Powdery Mildew
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Leaves yellow, wilt, die
Root Rot (fungus)
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Pale yellow spots on leaves; reddish brown pustules underside of spots
Rust (on plants)
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Leaves stippled, yellowing or bronze; dry out and drop may be webbing visible; sometimes galls form on leaves
Spider Mites
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Dark lesions on stems; roots rot
Stem Rot
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