[Rader Sidetrack]

I think there are possibilities other than that hive swarmed. One possibility is that the queen died sometime during the winter and the the drone cells are from laying workers.


More info on laying workers here: http://www.bushfarms.com/beeslayingworkers.htm

 

[Rader Sidetrack]

> How and why in the world does a queen lay drones only?

An unmated queen can lay drones. Drone eggs do not require any semen, so eggs laid by a queen exhausted of stored semen will be drones.