At this time of year this is the question that I am most frequently asked by beginners and by more experienced beekeepers. If you follow these topical tips that I try and send out regularly, you will realise that there is often no one straightforward answer. It all depends on how you manage your bees.
Leaving a super of honey or taking the supers away from the bees all depends on how you wish to manage your charges. And I would argue it all depends on what the level of varroa is in your colonies and how many bees you have got in those colonies. If you have done as the BBKA recommends you will already have extracted your honey, and you will have left an inspection board in for one full week in order to calculate the natural mite drop in your colony. If your colony is a medium-size one or a small one, then you will have taken back the super/s after one day once the bees have licked out the honey left over from your extraction. This is an easy scenario because if you need to treat for varroa then there will be no supers on the hive and you can use a thymol product like Apiguard together with an eke and that will clean up the bees ready to go into winter.
If you have a super full of honey and your varroa drop is still high then you can always take that super away from the bees, treat, and then put the super back on them. This will have the added advantage of encouraging them to put any nectar they collected this time of the year into the brood box, which is where you want it. However, be careful how that is stored because wasps and local honeybees can move into your garage or bee shed if they find that honey! The difficult situation comes when you have an extremely large colony with three or four supers on them. Removing all those supers and crowding the bees into the brood box may not be a very intelligent idea. Crowding bees at any time of the year can encourage swarming!
A large populous colony will no doubt have varroa and that can be building up at this time of year. They may still be collecting nectar and making honey and some people will still be able to do an extraction in early September. The catch 22 is that a lot of the treatments against varroa mite only properly work when the temperatures are high enough. And so, this treatment should be carried out now in August. And those treatments cannot be used if there are supers on the hive.
It is because I often experience the above scenario that I do not often treat in August but sublimate with oxalic acid in December. I know our French counter parts would argue that that is not good because it is the winter bees being made at the moment that are the ones that are going to carry the colony through the winter. However, I make one proviso. That is that if I find a huge mite drop at this time of year and distressingly see that there are a lot of deformed wings, then I will make sure that I treat. That is a good tip for you all – look now for DWV on your bees. If you see it, alarm bells should be ringing. And if alarm bells are ringing, do something.
Malcolm Wilkie 17th August 2019