Freezing will kill wax moths, all stages (eggs, larvae, pupae and
adults).  The question of how long to freeze depends on how cold is your
freezer.  From _Honey_Bee_Pests,_Predators,_and_Diseases_ (Morse and
Nowogrodzki): "... minimum treatments are required to kill all stages of
the greater wax moth: -7 dC (20 dF) for 4.5 hours, -12 dC (10 dF) for 3
hours, or -15 dC (5 dF) for 2 hours ... (Bulky materials - containers of
bee-collected pollen, combs containing honey, and so on - may require
considerably longer exposure times to reach killing temperatures.)"
 
Regarding the strain of BT, it is correct that there are many different
strains of BT and you must use the strain that specifically targets the
pest in question.  BT for Colorado Potato Beetle is not the same as BT
for asparagus or BT for cabbage.  I was surprised that ..._Pests,_
Predators,_and_Diseases_ did not list a specific strain of BT.  It is
my understanding (which may be flawed, we all know that by now) that
the product Certan (which contains the proper strain of BT to kill
wax moth larvae) is no longer offered in the states.  I do not know
the reason why Certan is no longer marketed, perhaps Andy can provide
the reason.
 
Aaron Morris - thinking there are times when you can't beat a good book!