Colchicum
Symptom Cause  
Corms gnawed, unearthed or eaten
Chipmunk
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Foliage may blacken by the first frost of autumn. Stems usually collapse
Frost Damage
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Foliage is distorted and corms are decaying
Mite
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Plants stunted, yellowed and may have root lesions
Nematodes
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Ragged holes in middle of leaves
Slugs and Snails
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Corms gnawed, unearthed or eaten
Voles
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