They may be so numerous as to run together and make the fruit crack. Lesions on twigs occur on current-season growth. They are purple to black, with indefinite margins. The lesions may run together and form a superficial canker. Early defoliation leads to small fruit, weak bud formation, and fall blossoming.
Infected fruit has no sale value and often is cracked and misshapen.
The sexual sport stage develop on fallen, overwintered leaves. Conidia, asexual spores, may also develop in the spots on overwintered leaves, or they may be produced in the previous season's shoot infections. Often the first infections do not occur until mid-June to the first of July. Secondary infections begin about 1 month later and reoccur throughout the season during periods of rain. Disease management Routine fungicide sprays normally control this disease in Pennsylvania.