Trevor, >>From my own experience, I keep about 5 of the best producers from one year for use in my breeding program. How many drone colonies do you maintain and what criteria do you use for your drone colonies? >>I know this because I have a record of the number of supers that come off hives because of my barrier system. I'd interested in learning more about your barrier system - please elaborate. I've seen row operations where the row end colonies had mediocare queens but still produced the most because the workforce numbers where greatly augmented by drifting bees. Waldemar Long Island, NY -- Visit www.honeybeeworld.com/bee-l for rules, FAQ and other info ---