Injury from the contact herbicide paraquat (Gramoxone Extra®) typically appears as rusty-orange spots or irregular-shaped blotches on leaves (see photo). At times this injury may look similar to black rot infections on leaves, but paraquat injury lacks the dark pycnidia (fruiting bodies) and the cream-colored center that occurs with black rot. This injury typically results from spray drift, so the damage is most severe on leaves near the ground.

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