This disease is usually present every year, but its severity varies tremendously from year to year. Cool, rainy weather in May favors infection by the fungus. The pathogen, Monilinia vaccinii-corymbosi , has two phases of infection. Overwintering ascospores infect the emerging buds and cause leaf and shoot blight. Conidia produced on this infected tissue will subsequently infect blossoms and young berries.
Infected berries are tan or pink in color and the hardened berries shrivel and fall to the ground.
Management of Mummy berry. Management of the disease includes several strategies, the most important being sanitation. Mummies should be raked up and discarded in smaller plantings. In larger plantings, the mummies should be buried by cultivating between the rows or by adding two inches of mulch. The susceptible cultivars Bluehaven, Bluegold, Coville, Northblue and Sierra should be avoided.