>
> Can anyone suggest how I can cure this problem?  Please keep in mind the 
> constraints of my climate:
>
Timothy,

This is very simple idea, and I dont know how many colonies you have, but I 
would certainly try,say, 3 groups of queens from 3 different stocks.
You could see if you saw any major differences in survivability. Keep all 
progeny in separate groups also. I highly recommend that one of the stocks 
be one touted to have shown resistance to both tracheal and varroa.

John Horton 

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