Answer: There are several types of fungus problems that affect raspberries, some not apparent until the fruit grows although infection occurs at the flower stage. They are spread by spores (carried by wind and weather) and infection can carry over from year to year on plant debris or blow in from infected plants. It can also be spread while picking. Careful attention to fall clean up can definitely help, but the weather is also a strong contributing factor so that some years are worse than others. To verify which one has affected your plants you might wish to take a sample to your County Extension (454-0900); they should also be able to suggest control measures and timing most appropriate for your area.
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