Why do Beekeepers Use Queen Excluders – When to place them and take them off
For many beekeepers a queen excluder is of their most important beekeeping supplies which assists the beekeeper manage the hive better. A queen excluder allows the queen to stay on the brood frames, on the lower part of the hive. The queen excluder confines the queen so she does not meander to lay eggs on the honey comb, which is higher, in the hive.
Another reason beekeepers use queen excluders is that it eliminates multiple supers the beekeeper will have to inspect during a hive inspection. Normally a beekeeper will have a deep super and a medium super which will be utilized as “brood boxes”. These brood boxes is where the queen in confined. Then the queen excluder is placed in the hive. By confining the queen, with a queen excluder, it keeps the queen focused on laying brood the same day after new brood has emerged from the cell.
Please note that the queen excluder will keep the queen and all drones from going into the honey part of the hive.
There are 3 types of queen excluders:
Wood Bound stainless steel grid. A wood bound excluder makes a seamless joint on the exterior of the hive. This type of queen excluder is built to last a good 10 years with proper maintenance.
Stainless steel excluder is also a good long-term investment. The excluder when maintenance will last 10 years. The stainless steel excluder will have some of the metal edge somewhat creased from the outside of the hive.
Plastic Queen Excluders are the newest trend in beekeeping. A beekeeper should look at these excluders as a throw-away item at the end of the season. With proper care, plastic queen excluders may last 2 years. This excluder will leave a small gap on the outside of the hive. 
The only real maintenance would need to do is when wax and propolis begins to cover and eliminate access to the hive and must be scraped off the queen excluder.
Queen excluders should be put on at the beginning of Spring before the nectar flow and colony build-up but with temperatures not going below 50 degrees at night. Once the low temperatures get above 50 degrees it is time to insert the queen excluder.
Please note that if you put the excluder on too early, the queen could be trapped in the lower part of the hive and be killed by the low temps at night. Always remember, heat rises, and your colony needs to conserve the heat within the hive during the cold months.
At the end of summer, when we harvest our honey, we will want to take off the queen excluder. That way, the queen can begin her migration to the top of the hive. During the summer the queen goes low in the hive due to it being cooler. During the winter the queen will live at the top of the hive where the warm can be found.
Harvesting honey and taking off the queen excluder, normally happens by late July to mid-August.