First off, Merry Christmas and Happy New Year! The colony of Italian bees (although now they are less Italian, having been bred out by their new King Island queen) have been doing very well in their Langstroth hive, but it was well and truly time to move them into their top bar home.
Phil Chandler advocates the “chop’n'crop” method to achieve this, where by one chops the sides off the frames, and then crops the comb to fit the inside of the top bar hive profile. Watching the video of this process, it seems easy enough – in practice, we found that the “chop” requires a saw, and the “crop” is messy and would kill a lot of brood. Obviously this entire process is very disruptive to the hive, and since I was in no hurry to get them out of the Langstroth hive, I decided to let them transfer themselves. The principle I was relying on was the same that underpins Warré beekeeping: bees will move their brood downwards if possible.
The TBH a Langstroth shaped hole in the roof. The follower board is partly under the roof at right
I built a Chandler dimensioned top bar hive, but placed thicker side rails (35 x 90mm) to give sufficient width to sit the Langstroth hive on top without it overhanging, and I also cut some thinner top bars (about 30mm wide) to allow for gaps for bees to pass through and up into the Langstroth box. I placed the follower board (a solid movable end that allows the top bar to be slowly increased as the bees expand) to line up with the edge of the Langstroth box. This gave the bees eight top bars matching their eight existing frames. I made a shorter roof allowing 355mm (the width of the Lang box) to remain exposed. I finished this by stapling a double thickness of black plastic (pond liner) to the plywood top for waterproofing. Rather than messing around with hinges (since it had to mate up with the other hive) I just placed four locating pins into blind holes. Given its shorter length and lighter construction, lifting the roof section off is not an issue.
A few dozen bees left on the baseboard
Once I got the new hive into position next to the old one, it was (amazingly) simple to lift up the Langstroth box and place it onto the top bar hive. Initially, the resident bees didn’t even seem to notice, apart from the few dozen on the baseboard. This made me think that the Warré folks are really onto something when they add new boxes at the bottom of their hives rather than the top as per ‘traditional’ bee keeping methods.
The Langstroth box was attached and sealed with gaffer tape, because I didn’t want bees trying to enter through little gaps in the woodwork. Finally, I placed some gaffer tape where the box met the peaked roof, to direct rain away from the join. The intent is to avoid “actively” inspecting this hive until such time as the bees have moved down into the top bar chamber and I can remove the Langstroth box from the top.
All taped up and nowhere to go
By the time I was taping up the hive, the foraging bees were returning and wondering how to get inside. You could almost hear them thinking “Hang on, there used to be an opening just here” as they walked down the front of the Langstroth hive. There were a good few dozen bees trying to get into the hive via the mesh at the bottom, and a persistent half dozen or so that were convinced they could sneak in where the roof met the hive, which was sitting proud of the side rails by 3mm or so.
After about 30 minutes, the bees seemed to have it all figured out, and were coming and going via the new entrance. I climbed under the hive, and with the help of a very bright torch I had received for Christmas, I took a photo of the bees moving through the gaps between the top bars.
This photo was difficult to take
The next day, I didn’t notice any bees trying to get in where the old entrance was, and there seemed to be more activity generally – I suspect that the bees have renewed vigour now that they have some room to make comb.
Three days later at about 10pm, I did another one of these “underneath” inspections, and saw the bees building comb on the top bars, so I think it’s safe to say that the technique is sound. Hopefully when I do the next check, I’ll see some decent combs being developed and take a photo.