>>Insofar as I can find a practical way to do it, should I try to isolate my colonies with heavy mite loads?

You may be able to isolate your other hives from the heavy mite ones with distance but consider that there may be other beekeepers near where you decide to place your heavy mite hives...  I am sure they are not keen to pick up anybody's mites...

Why not treat with OA dribble when they go broodless?  You'll get 90-98% kill if done correctly and it will take you 2 minutes per hive for the application.

I have found it to be the only treatment I need to have a mite-worry-free year.

Waldemar

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