Here in Caledon Ontario( 80W44N), I have had Varroa for three
years.  The slicers found a small sample of HBTM last fall.  I missed your
discussion on mineral oil.   Please discuss the timing and methods used as
well as the type of oil.  Our Provincial Apiculture people recommend
Apistan in the fall and Formic Acid in the spring.  So far my hives are
strong but would like to know more about alternatives.  Today's weather was
fair, with the day-time temperature at +2C (36F), and plenty of bees flying.
                        Thanks