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Reddish-Purple Powder on Multiple Plants: Sooty Mold from Insects

Neighbors' Plants Covered in Washable Colored Dust

Spider lily, crepe myrtle, hydrangea affected. Material washes off, no spraying done.

Expert Identification

Since on unrelated plants and washes off, it's a residue, not fungus. Expert sends bulletin on Sooty Mold (PDF link). Sooty mold grows on insect honeydew.

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