Changes

This is the time when you should begin to remove the sealed drone brood that have an increased harbor a proportionally higher number of Varroa mitesthan worker brood. You can diminish the mite population considerably by continuously growing having the bees rear drone brood and then removing them regularly. The drones are usually reared until mid-July, after which the drone removal can be stopped.

You can continue removing drone brood for as long as the colony is willing to grow rear them. The swarms and nucleus can be treated for Varroa with treatments like evaporating thymol or trickling oxalic acid in as early as midsummer if no honey is harvested from these colonies during the same season.