Royal Fern
Symptom Cause  
Leaves wrinkle/curl/discolor/stunted/ die
Aphids
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Rotten spots on fronds; odor present
Bacterial Soft Rot
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Young ferns rot at base and collapse
Damping-Off
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Smooth holes in fronds
Japanese Beetles
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Gray spots on leaves
Leaf Blight (fungus)
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Reddish brown or blackish spots on fronds
Nematodes
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Failure to thrive
Overcrowding
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Deformed fronds
Overfeeding
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Fronds yellowed; small bumps on fronds
Scale
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Ragged holes in fern fronds
Slugs and Snails
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Rows of black dots under leaves
Spores For Reproduction
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Fronds flecked; whitened; then wilt and turn brown
Thrips
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Fern roots damaged; holes in fronds; plants wilted
Weevils
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