Hello Ed
                A third method is to insert a super frame (i.e. a frame
shorter than your brood frame) fitted with normal worker foundation in the
brood nest. Your bees will build normal cells within the frame and drone
cells below the bottom bar to the remaining depth. When capped, and with the
mites safely sealed in, you can cut off the drone cells and replace the
frame for another cycle.

This works well for the single brood chamber setup usual in the UK. I'm not
sure about double brood chambers, but it should be ok.

John Burgess, Editor Gwenynwyr Cymru/The Welsh Beekeeper
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