Freezing capped drone brood is reported to be very effective in Varroa
control.  For this purpose, it would seem to be best to use foundation made
specifically in drone size.  This foundation is now sold by most or all US
dealers.

I freeze it for at least 24 hours, and probably an average of 3-4 days.
Then I use the frozen frames to replace drone frames that I take from
another hive.

As to how effective it is in controlling Varroa, do the math.  Assume 80% of
foundress mites (females reproducing) choose drone brood and those that do
produce 3 daughters.  Assume the other 20% are in worker brood and produce
1.5 daughters.  Work out the numbers (separately) over 120 days.

Astounding?

Note that an article by Tom Seeley in the June Bee Culture says that if you
increase the amount of drone brood produced, you will decrease honey
production.  However, this is a big "if", as the comparison is with the
amount of drone brood that would be produced with your present frames.  Tom
has documented that feral bees dedicate approximately 20% of their cells to
drone production.  Do your frames contain less than 20% drone cells?

Lloyd
Lloyd Spear, Owner of Ross Rounds, manufacturer of comb honey equipment
for beekeepers and Sundance pollen traps.
http://www.rossrounds.com
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