|Two adult flea beetles on strawberry foliage. The "lacy" feeding damage is characteristic of many foliar feeding beetles. Photo: John McIntyre, Duplin County NCCE.|
|Adult flea beetle with John's figure for size reference. Photo: John McIntyre, Duplin County NCCE.|
So, now that I believe we're dealing with a flea beetle, what should the affected growers do? I do not think that the foliar injury in the images above will result in yield loss, and I suggested that the growers not treat if only foliar feeding was present. However, one larva John found had tunneled into a strawberry. If lots of larvae are present and potentially feeding on fruit, this is of much greater concern. Unfortunately, most of the pesticides effective against flea beetles are broad spectrum and may flare spider mites in strawberries, which have already become problematic in strawberries this spring throughout the southeast. There is one narrower spectrum material that might work can be organic as well, and I suggested to John that if larvae were present, this might be the best choice. See a note about pesticide recommendations.
Update, 10 April 2012
I took the adult beetle and larval samples to Dave Stephan, insect identification expert at the NC State University Plant Disease and Insect Clinic this afternoon. Dave agreed that it does indeed look like it is from the genus Altica, but he suspected that they were too small to be grape flea beetle. He is going to run them through a key to determine if they are strawberry flea beetles or something else entirely!