Regarding timing of Varroa, it was noted that a successful commercial beekeeper
in the Northeastern United States treats with Apistan for Varroa in February.
 
Here in Central Texas, an experienced beekeeper recommends putting strips in
the hives the last week of December, when there is no brood.  Egg laying
here begins about the first of January.  The thought is that if you treat when
there is a break in brood production that you will (hopefully) kill all the
Varroa mites more easily and quickly because none of them are hiding in capped
brood cells.  Makes sense to me and I intend to do it.
 
Layne Westover
College Station, Texas