Fruits thinned at or after pit hardening also provide a good medium for the fungus and are an important source of inoculum for mature fruit infection. The fungus overwinters primarily in dried fruit called mummies. Primary spores are produced from mummies on the ground or on those still attached to the tree and are dispersed by wind. The presence of free water on the petal or fruit surface is necessary for infection. Secondary spore production on blighted blossom serves as inoculum for infection of maturing fruits later in the season.
Sanitation is very important in the overall management of brown rot.
Fruit thinned after pit hardening should be removed from the orchard during thinning operations. After harvest, remove all rotted fruit and mummies from the trees and ground. Prune out twig cankers during the summer months. Avoid pruning in fall because this can increase the incidence of Cytospora canker. Wild plum thickets are an important source of primary and secondary spores and should be eradicated adjacent to peach orchards.