Impotent AMF is a thought. I did make a spray of Entrust (spinosad) in early August on heavy-set varieties to further knock down peak AMF in conjunction with trapping. Honeycrsip is the prime target as AMF seem to go for this cultivar more than all others. I could see holes being made then having time to decay and thus take a more dried up appearance. I could also see a fly with an altered state of consciousness making two or three such holes side by side. It's the volume of the attacks that confuses me, and the fact that the flesh rotted into the harvest window as a result. It's definitely not stink bug as I would see those.
Sourcing GF-120 at a reasonable price has proven difficult. I know Harmony Farm Supply in California has it at a cost of about $200 a gallon. I've long intended to make a homegrown rendition using Entrust on hand, guestimating a half ounce of commercial spinosad concentration would play out about right in this recipe:
Fruit Fly Bait Recipe:0.02% spinosad (active ingredient)
1 ounce live baker's yeast
0.5 pound sugar
0.5 pound dried brewer's yeast
1 gallon water
Spot spray on undersides (to lessen rain loss) of leaves near developing fruitlets
Thanks, Leslie. Now to remember to do this come mid-July and catch those darn whizzbangers!
Lost Nation OrchardZone 4b in New Hampshire