The blossom clusters and twigs which become infected in spring will then provide a secondary source of spores for fruit infection later in the growing season. There fore, it is important to control these early infections. The disease is most damaging in years when wet weather prevails during bloom and from 3 weeks prior to harvest until harvest. Control Brown rot cannot be effectively prevented by one or two sprays or dusts applied in the spring. A combination of both cultural and chemical control measures as outlined below is required for control of brown rot.
Orchard sanitation is of major importance in controlling brown rot.
Trees should be pruned to eliminate weak and dead wood, including small twigs that may have been killed by brown rot the year before, and to open them so good spray penetration can be obtained. Mummied fruit left on the tree after harvest and those on the ground should be removed in early spring and either burned or deeply buried. Rotten fruit that appear in the trees early in the summer should be removed immediately since they are a source of infection for fruit at harvest time. Chemical Control Sprays must be applied at the proper time for good control of brown rot. Equally important as the timing of sprays is the spray material itself.