A tray for positioning in an exit path of a bee hive comprises a base, a bee entrance end, and a bee exit end. Spaced apart side walls extend upwardly from the base. The sidewalls extend generally lengthwise between the bee entrance end and bee exit end. A plurality of posts extend upwardly from the base and are positioned between the bee entrance end and the bee exit end. The posts are generally circular in cross-section. The posts act as obstacles around which the bees must walk to reach the bee exit end from the bee entrance end.