Haloes on Milkweed

Haloes on milkweed

This leaf is tough to assess. The scattered black dots look like classic ozone stipple. Do you see the large black lesions with purple haloes? Can you find smaller lesions with light purple haloes too? This leaf might have ozone injury and a mimicking injury with purple haloes. Perhaps there are areas injured by ozone that are also susceptible to infection by a disease causing the haloes. Probably the best way to rate this leaf is to call it possible ozone injury.

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