At first these galls are small but continue to enlarge each year, becoming very rough, and, each spring, become covered with dark, olive-green, felty growth. Branches may be girdled and die. Apiosporina morbosa Prune and destroy galls, cutting several inches below the gall whenever they are found but especially during dormancy. Remove unwanted Prunus species from the area. Brown rot Flowers collapse and brown quickly.
Small cankers form on twigs and gum oozes out.
Ripening fruits brown and shrivel as they become covered with tan to gray masses of spores. While many fruits fall, some shrivelled mummies are left on the tree. Spots may fall away leaving a shot hole appearance. Infected leaves yellow and fall prematurely. Necrotic ringspot Leafing out is delayed in the spring on individual branches or the entire tree.