Queen cell size

[fatshark]

I've not seen this discussed before and wonder what others think …

We ran a queen rearing practical course on Saturday, with about 8 people doing grafting for the first time. The lighting wasn't great and some were struggling to see suitable sized larvae. In parallel an experienced colleague grafted from a 'sister' frame from the same colony.

My expectation would be that the experienced grafter would choose smaller larvae, whereas the beginners were more likely to choose ones that were a bit too big. The two cell bars went into different "Ben Harden" cell raisers.

I checked the cells again this evening. Take was better by the experienced grafter (~80+% of 18). However, the beginners did reassuring well (~50% of 18). However, all the drawn out cells by the experienced grafter were appreciably shorter. All the cells I looked at were pretty well charged with Royal Jelly, but (again) the lighting wasn't good enough to check the larvae size.

After all that … is cell size an indication of the age of grafted larvae? Could you use this an an indication to choose the youngest larvae which should end up the best fed?

I don't think it's anything to do with too few bees in the box with the higher take. Both are pretty busy.

[mbc]

struggling to see suitable sized larvae.

I always think I've picked larvae that are too old if I can see them clearly.
The differing cell sizes could be down to the cell raisers rather than age of larvae. If you have a bar of queen cells its fairly self evident which ones, if any, should be culled- they will differ from the norm. I usually cull if cells are smaller than their neighbours or look malformed in any way, some breeders "candle" their cells but I've not learnt the trick.

[Jon]

I would agree with MBC. The difference is probably something to do with the cell raiser colony rather than the size of the larva selected.

[fatshark]

OK, I'll check them every day and see if there's a difference in when they're sealed.

Although it's not 'candling' a commercial friend of mine always uses JzBz cups. By holding near to emerging cells against the light he can tell - through the semi-translucent base of the cup - which have ample jelly left. Those that don't he discards, reasoning that they haven't been well fed.

[prakel]

Joe Latshaw makes some worthwhile observations on larvae size in his pdf 'Queen Rearing Basics' I reckon that this is one of those should-read documents for anyone starting raising queens of their own.

[prakel]

Although it's not 'candling' a commercial friend of mine always uses JzBz cups. By holding near to emerging cells against the light he can tell - through the semi-translucent base of the cup - which have ample jelly left. Those that don't he discards, reasoning that they haven't been well fed.

There's a theory which I've come across somewhere in the past that not removing the cell after emergence helps to stabilise the colony while the virgin is waiting to mate by allowing the remains of the jelly to be fed back into the colony. No, I don't have any references to research on the subject, it's just 'stuff' that I've heard mentioned but I suppose that if there is anything in the idea then the more jelly left in the vacated cell the better.

[fatshark]

Thanks prakel … I see that Latshaw makes a similar case as my bee farmer friend re. amount of jelly left.

Re. stabilising the colony … not heard that one. When using mini-nucs I always remove the vacated cell the day after emergence (just so it doesn't get all jammed up) - they've usually been cleaned out by then though.

[prakel]

It's not something I'd give a great deal of credence to but I am a bit of an anorak when it comes to these off the wall ideas -you never know when they'll start tying in with other things. Personally I tend to leave the cell initially but that's simply because it's just a bit of wax mounted on a small stick, hardly a priority.

[fatshark]

Thought I should close this thread off by reporting the final size of the sealed cells. mbc was spot on … the cell raiser that started making smaller cells carried on the same way. The final cell size was extremely small, maybe 1cm beyond the end of the JzBz cup. The take was great, actually 16/18, but they all look like scrub cells. In comparison, the other cell raiser generated 'standard' sized sealed cells.

[Jon]

You can often get a decent sized queen out of an average looking cell.
I have just bought an incubator and I guess you can let the virgins emerge and then make the judgement whether to discard a small queen as opposed to judging just on cell size alone.