I hate to disagree with someone as knowledgeable as Andy Nachbaur but I
would have thought that the majority of the queens movement would have been
within the central region of the hive, the reason why I have witnessed in
France (or it could have been Germany) squares of thick clear polythene
sheeting used as queen excluders. These were cut to the hive dimensions less
about two inches on each of the four sides. According to the commercial
beekeeper they worked well and he rarely had a queen pass them.
 
Ken Hoare
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