I'm not sure if I am recalling the correct device, but -- The board is a piece of wood sloping to the ground, which is set up in front of the hive. It is positioned to leave a few inches-gap between it and the hive entrance. The bees are then shaken off the combs at the base of the board. When they run up its surface, the older bees go straight across the gap into the hive, but the younger bees (and queen?) end up clustering at the edge of the board, like a swarm. Then they can be taken away and hived elsewhere. Or that is the jist of it, I think. Can anyone elaborate? Thanks muchly, Joel Govostes Freeville, NY