Field library

Early Blight

Brown spots with clear concentric rings, like a target, appear first on the oldest lower leaves and work upward. It hits crops that are short of nitrogen or under water stress hardest, and unlike late blight it spreads slowly in warm dry weather.

How to scout

Look at the bottom third of the plant. Target-like rings inside the spot separate it from late blight, which has no rings and looks water-soaked.