Hi Guys, I'm enjoying this discussion...
>What I am saying is that constant introduction of new genetics or
re-introduction of other genetics not naturally encountered in a area,
stops the ability of the environmental factors pertaining to the
location having a chance to act to bring about stability.

I've been faced with decisions about queen selection ever since 20 year's of 
my work was wiped out when varroa first decimated my operation..
I started over with standard production stock, which worked as long as 
Apistan worked, and there were no ferals.
When Apistan later failed, I selected for survivors, ferals, and SMR--a 
waste of two years (unless you're a breeder selecting for survival genes, as 
John Harbo did).
Finally, I restarted with a diverse mix of strong producing stocks with some 
degree of mite tolerance and hygienicity.
It took two more years to flood the woods around my mating yards with good 
genetics.
Now I'm following Dave's (and Joe's) approach and selecting from a large 
number of my most productive queens, who also demonstrate good mite 
tolerance.
I bring in a small number of queens from other local beeks or other breeders 
each year to keep slow influx of diversity, at a relatively low level.
All my stock is open mated.
I am in no way saying that this is the best approach, just sharing what 
appears to be working well for me.
Randy Oliver

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