I have been ask how I check for mites and what can be done about them this time of the season. The what can be done now answer is as usual, “it depends on the hive.” If the hive has honey supers on that are going to be harvested, my answer is simple – don’t use mite treatment. The formic acid treatment is legal but has a temperature restriction. I don’t know of any other proven treatment that can be used when honey supers are on on the hive.
If there is no honey super, I treat to correct the problem. I have moved the honey super(s) off the hive so I can treat. It depends on several factors before this is a viable process. The hive can also be split with a new queen added to the queen-less split. I try to get the mite load under control before honey flow so that I don’t have this issue.
The two methods I use to check for mite levels are the 24 hour mite drop board and the drone brood examination method. The mite drop board requires a 2nd trip to the beeyard so I prefer the drone brood method.
To check for mite level at this time of the season, I simply open 10 drone brood cells, pull out the larva, lay them out on a flat surface and look for the brown mite on the white larva. Simple, fast and easy.
If I find more than one or two, I re-sample the hive and plan accordingly.