Ask a group of beekeepers about queen excluders and you are likely to encounter passionate feeling for and against using them. Like so many other things in beekeeping, you have to chose what you find works best for you.
Queen excluders are metal or plastic grids that are placed between two hive bodies. The grid openings are 5/32 inch, which is wide enough for a worker to pass but too small for a drone or queen to squeeze through. Handle your queen excluders carefully because if any part of the grid is damaged, the queen will find it and slip through.
Arguments for using queen excluders:
- Keeps the queen from laying in the supers
- Prevents the beekeeper from accidentally removing the queen with the honey supers
- Keeps the wax in the supers lighter since there are no brood cocoons to darken it
Arguments against using queen excluders:
- Nectar loaded bees may be reluctant to pass through the grid
- This leads to bees choosing to backfill the brood nest with nectar
- If the queen’s laying space gets filled with nectar the hive will swarm
- Swarming means less, if any, of a honey crop
- Drones can be trapped above the excluder and will die unless the hive has a top entrance
- If the excluder is not removed before winter, the cluster may move up to the honey above and leave the queen behind to freeze
Queen excluders are handy to have on hand for hives where you can’t locate the queen. By placing a queen excluder between the hive bodies and waiting four days you can determine which box the queen is in. She will be in the box with eggs. Queen excluders are also used to run two queen hives. The excluder keeps the queens separate but allows the workers to mingle.
I haven’t found cause to use one yet, but I do have one on hand in case I need it for help finding a queen.