Re: treating mites
i hope i'm not repeating myself too much on this, but this is where the brood break may come into play.
waiting until all or at least most of the brood has emerged, removing the bottom board, and then dusting will hopefully dislodge most of the mites and let them fall to the ground.
this means pulling or pinching the queen and letting the brood hatch, or waiting until they stop brooding in the fall (which would probably be way too late to do any good)
here's my plan (subject to modification based on expert advice received on this forum )
if i find a high count in the spring, that colony gets dequeened, brood is allowed to emerge, the frames are dusted and split up for nucs. (sacrificing honey production for bee production)
if i find a high count mid to late summer, the queen gets pinched, the brood is allowed to hatch, they get dusted, and are then combined with a strong nuc.
beekeeping since june 2010, +/- 20 hives, tf