Expert Problem Solver

Fly Speck

Fly Speck
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Bonide Solutions:
Fly speck is a disease caused by the fungus, Zygophiala jamaicensis. Fly speck looks like true “fly specks” characterized by sharply defined, small, black, shiny dots in groups of six to 50 or more that appear on the surface of the fruit. The individual “fly specks” are clearly separated. Fly Speck requires water on the fruit surface to infect the wax surface of the fruit. Disease outbreaks are favored by extended periods of above-normal summer temperatures combined with frequent rainfall and high humidity.
The disease overwinters on twigs of various wild woody plants, especially wild blackberry and raspberry canes. Growing raspberries or blackberries near apple trees increases the risk of fly speck. Try to keep apples and brambles as far apart as possible.
Fly speck is most common in the damp, low, shaded areas of the orchard. Any practice that promotes faster drying of the fruit greatly aids in control. For example, prune trees annually to an open center for maximum air circulation. Thin fruit a few weeks after petal fall so there is only one developing fruit every six inches.
Remember that the disease is superficial and generally does not impact the quality of the fruit. Remove by washing, rubbing, or peeling the fruit as this results in fruit that is suitable for eating or cooking.