What do beekeepers use to calm the bees?

Answer 1

Beekeepers use smoke to calm the bees down. They do this by making a small fire in the smoker and squeezing the bellows to make the smoke come out. When bees are frightened they send out a special scent to alarm the other bees to attack. When a beekeeper uses smoke on a beehive, the bees are no longer able to smell the alarm scent so they keep on working in the hive.

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There is a second explanation for the use of smoke. In the distant past bees were woodland creatures, living in hollow trees. They learned that if they smelled smoke there must be fire nearby and it was possible they would have to leave their tree in a hurry and start a new colony elsewhere. To prepare for this they would go to the honey stores and swallow as much as they could ready to take it to the new nest.

That instinct is still there, so smoked bees fill themselves with honey which results in two things: like you after a big meal they tend to be more calm and not be rushing around; and, with their stomachs full, they find it difficult to bend their abdomen down in order to sting. Both of these make it easier to work on the hive.