Re: Is the middle of October too late to treat for mites in Upstate NY
A brood break doesn't reduce mite population much. I agree that there will some less mites as seen by daily drop however not a huge lowered mite population. Mites can live 6 months and more.
The brood break slows the mite population build up. However, also slows bee population build up as well.
I don't put much faith in brook breaks by themselves. A brook break along with an OAV when minimal capped brood or installing Apivar during the brood break is much more effective.
Zone 3b. If you always do what you always did, you'll always get what you always got!