Cranberry fruitworm damaged blueberries. When several (3 or more) berries are damaged and large amounts of frass are present, it's likely that the fruitworm larvae have already exited the fruit to pupate. Photo: Bill Cline
Bill Cline, NCSU blueberry and muscadine pathologist, has posted a nice summary of some of the causes of "funny looking" blueberries in the southeast at the NCSU Plant Disease & Insect Clinic blog. Among the pathogens & mechanical injuries described is one type of insect damage, cranberry fruitworm (above). I wanted to add two more funny looking blueberry issues to the list.