Is this a disease on my plants?

Asked September 15, 2015, 1:42 PM EDT

Can you tell me if this is a disease, and how to treat it? I have more than 25 plants. What is the prognosis? It looks pretty bad up close in the photo.

Hennepin County Minnesota leaf galls

1 Response

The leaf spots are not a disease. They are galls probably caused by Aculops rhois, the poison ivy leaf gall mite. Although the condition looks serious, the galls have little long-term effect on the plant's health. No control is needed.

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