My largest colony is on two 14 x 12 brood boxes and at the week-end showed signs of swarming with a number of charged queen cells and 2 additional ones with eggs in. The colony has plenty of space but as it is very big , 13 frames of brood, it seems to have decided to make preparations for swarming. Not being prepared I went back 2 days later to perform a split with a modified Snelgrove board. The technique was described by Ken Basterfield in Beecraft (April 2012).
It’s similar to the technique I normally use to raise 2 nucs above a brood box in a single stack system, but looks simpler and involves less manipulations. My usual split board is a solid floor with 2 entrances on opposite sides of the same face. So I made up a new Snelgrove type split board by cutting 2 entrances on opposite edges of a crownboard with one on the upper side and the other on the lower side. I then covered the porter escape slots with wire mesh on both faces.
Modified Split Board
At the last inspection I used a queen excluder to confine the queen to the bottom box. Fist step was to take off the super and the top brood box and set to one side. I found the queen and put her in a clip cage whilst I went through the bottom box. The bottom box and floor were turned through 180 degrees and the entrance block closed off. I shook the bees off the frames to make sure I didn’t miss any queen cells knocking down the queen cells the bees had started in the last 48 hours since my last inspection – 3 charged ones and 2 with eggs in. I took a frames with mainly eggs from the bottom box and swapped this with a frame of stores from the top brood box. The modified split board came next with the upper entrance open for the top brood box in the same orientation as the original lower entrance. The entrance at the rear was opened up for the lower brood box.
The theory being the flying bees from the lower box will return to the front of the hive where the old entrance was and crawl up to the new entrance boosting the bees in the top box. This is different from most other methods using a split board as they normally ensure that the flying bees return to the parent colony, i.e. bottom box. But as the 2 brood boxes have a similar amount of brood combs it means that they should both be strong enough to rear the brood and the foragers can still access the super above the top box.
The frames with the open queen cells could have been moved into the top box, but as I had shaken them I decided to let the bees draw their own queen cells from one of the existing brood frames or even from the transferred frames of eggs and larvae.
I will inspect in 5 days to select just one queen cell for the top brood box and if there are any spare ones transfer them to Apideas. It will also give me a chance to inspect the lower box and check that it has no queen cells and enough bees. If there aren’t enough bees in the bottom box I can reverse the split board and boost it with the flying bees from the top box. The bees had started to draw the comb on the Apidea frames that I mounted on a top bar and put into the super at the week-end.
It will be interesting to see how the technique works.