A plastic device which allows bees to pass through only one way, and one at a time, by pushing between two flat springs held in a funnel shape.
When inserted into the correct sized holes, in a crown board, it turns the crown board into a clearer board. Drones may get stuck in the device and block it.
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I am a beekeeper and an allotment grower and this site features articles on those subjects including recipes made from the produce from my allotment and from my bee hives. I have an interest in a great many things (too many actually) and some of those experiences, and the joy and learning I acquire from them, may also randomly appear here.