Leaf infection shows reddish spots with dark borders and, if numerous, leaves yellow and fall. Stem cankers are produced as discolored more or less extended darkened areas which may crack open.

Close-up of a spot with a ring of raised, spore-producing bodies ("acervuli") within spot.

Spore-producing bodies ("acervuli") and spores under dark-field observation.

Spores of the anamorph fungus Phloeosporella.