JoJo36 wrote: ↑20 May 2021, 18:40
Hi Adam
Do you double brood to avoid swarming or just generally to get the colony to expand more?
I know some say they hardly get swarms with double brood??!!
There are two reasons for going double brood:-
1) In order to get the largest number of foragers the idea is to not restrict the laying space available to the queen. If, for example, you see an arc of un-filled comb in the first super above the brood and excluder, that's laying space that the bees have created for the queen to lay in which she can't get to which says to me that we could have had more bees if we had allowed it. Without enough room you will be more likely to see comb being drawn below the brood frames and down towards the hive floor. (Or in a WBC, I have seen comb and brood between the brood box and lifts - not my colony that one!).
2)Lack of space is one of the reasons for colonies to swarm, so giving bees enough room means that you knock that problem out of play - unless the queen is really going to push a lot of eggs out.
In normal years my queens usually lay 14 - 16 frames of brood. Occasionally I have had as many as 20. As I don't want to encourage swarming, I give them room. I could use 14 x 12 frames which are around 40% bigger than DN4's, however I have tried them and don't like them too much. Brother Adam's view was that large frames are better than (more) small ones although if the bee space is OK, I see no issues with double brood as the queen is happy to lay in both storeys. If I put an empty brood box under a full one, the queen can be reluctant to move down to the lower box which is why I split the brood vertically as soon as I get to two boxes.
The downside of giving too much room if the queen isn't fecund enough, is that the brood box is packed with stores and there is less in the supers. Managing double brood boxes with a full inspection of 22 or 24 frames does take time of course. I have to admit that I do cheat on occasions and tip up the top brood box and look for queencells on the underside of the brood frames which is a likely place for swarm cells. It's not infallable but with clipped queens and ones that are not too swarmy, it's a chance I sometimes have to take and usually get away with it. [I would hope that most of my queens don't swarm in their first year].