I'm an old retired actuary who took up beekeeping three years ago. I
have also spent a number of years on the Westchester County (NY) pest
management committee and know that it is a violation of federal law to
use a pesticide in a manner other than as directed by the label.

While not a chemist nor a biologist it seems to me that the mites that
survive in a hive that is over wintered with Apistan will be the mites
that are resistant (or most resistant) to fluvalinate. As the survivors
breed they will pass on their resistant genes. Is this overly simplistic?

But here is something to consider. My daughter keeps bees in an area
of New York State where the mites are resistant to fluvalinate. In my
area (lower Hudson Valley) fluvalinate still works. While I would not
do what I'm proposing, why not transport my mites to her area and let
them interbreed? If we have bred resistance into the mites in some
areas why not breed susceptibility to fluvalinate into resistant
mite populations?

Jim Grefig
Crugers, NY