Not fruit-related, but I suspect this group might be able to help...
I received some large logs of what I believe is Elm over the winter.
Yesterday while walking the yard, I found them teeming with what I
believe to be adult borers of some kind, but I've been unable to
positiviely identify them. They're black with yellow markings, and
range in size from about 1/4" to maybe 3/4" long. Here's a photo of
one: