Rhubarb
Symptom Cause  
Plant stunted, declining; leaves wilt, turn yellow or brown; young trees wilt and die
Crown Rot
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Small black spots on oozing stalk
Rhubarb Curculio
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Tree stunted, declining; leaves wilt, turn yellow or brown; young trees wilt and die
Root Rot (fungus)
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Plant weak/stunted/disfigured; small spots, lesions start on leaves/move to entire plant
Stem Rot
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Yellowing of foliage and gradual defoliation; plants may become stunted
Verticillium Wilt
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