A: Over the years, debris and mites can build up in the nest tubes which could be harmful to the Pollen Bees. As Pollen Bees emerge at different times throughout the season, it can be hard to see which nest tubes are empty and which are in use, making cleaning difficult. The Emergence Chamber solves this problem by covering the nest and providing a small hole in the bottom which allows emerging bees to crawl out, but makes it unlikely they will find their way back in. This means that no new bees will nest in the tubes and they can be cleaned out as soon as all the bees have emerged. If you are using an Emergence Chamber, it is a good idea to have a fresh nest set up nearby so the emerging bees easily find a new home. >More information on Emergence Chambers.