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Cellsize Differentiation Test

There were bugs in the original test, which consisted of alternate strips of 4.9 mm and 5.45 mm foundation with bee space gaps between. I hope this revised version will help in assessing the cellsize which a strain of bee is currently adapted to.

Whilst its results may be contentious, I urge you to keep an open mind.

There are many that think the current cellsize is OK for their bees. There are some that deny the incremental increases during the last century or more. My personal view is that our bees would be more productive, and maybe more resistant to disease, if we returned to the status quo.

I think it is worthwhile trying this test, even if you have no part in the cellsize debate, as your results will generate useful information for further analysis by others.

This test stems from research that I had been conducting during years 2000 and 2001 into the cellsize of honeycomb (much of the early work has been done by Dee Lusby). The more that I look into this cellsize issue the more that I realise that we have led ourselves astray and that we need to re-appraise all the work that has ever been undertaken in this field.

My original motivation in starting to look was to be able to use the size of the worker cell as a method of discriminating against Italian strains of bee in my own breeding program... But I have had further thoughts that it may also help to isolate Amm strains.

The test is simple...

Freshly made brood frames... (so that there is no possible repellant or attractive force at work) a strip of special foundation is firmly fitted, without wires, so that the weight of drawing bees does not pull it out or make it sag. (I personally intend to use a clamping strip fitted using small wood screws.)

This is what the foundation looks like.

Cell Size Test Foundation

Place one frame in each of your colonies in such a position that the bees will need to draw it (just inside the fringe of the nest).
Look at these test frames after 6hrs, 12hrs, 24hrs, 48hrs to establish which patch (or patches) of cells is being drawn more favourably by the bees. (The differences in cellsize are exaggerated in the illustration.)

The special foundation is only 72 mm deep and so a group of bees clustering for wax drawing will easily cover a patch on both sides, with contact and communication between such groups afforded by extension of the cluster below the bottom edge of the foundation.

The principles behind this test are as follows:-
There are six sizes of cell involved (but see revision below)

7.2 mm... Drone foundation (originally Thornes manufacture)
6.3 mm... Drone foundation to suit 4.9 mm workers (my own manufacture)(project not yet complete)(This section may be changed to 5.9 mm in the light of some other work on 640 Cellsize
5.7 mm... Thornes foundation
5.45 mm... From my Leaf Products foundation press
5.2 mm... not yet resolved (Either an impression will be taken from 5.2 mm pierco plastic foundation or I will make a sample sheet from John Groocock's Brazilian roller mill).
4.9 mm... several possible sources (I am currently looking for a sample with raised cell walls to match the other sizes) (this is now resolved due to the production by Dadant of 'proper' 4.9 mm foundation.

The oblique groups of cell (30°) are due to the desire to avoid transition or part cells. Also to spread the influence of any particular cellsize over as broad an area as possible.

The gutters between strips of cells are of 3 mm thick solid wax, and are raised to form a smooth convex rib, so that the bees initial efforts are concentrated on the actual cell patches. (This avoids any influence from part cells at the edge of a patch that might give rise to transition cells.)

The pattern of six patches is repeated so that no matter where a cluster forms it has reasonable access to all cell sizes This can never be 'perfect'. Each patch is four cells wide apart from the triangular extremities which contain a few extra cells as some would be masked by the groove in the frame sidebar. I think the outermost parts of this foundation have little influence in any case as we are looking into the bees short term reactions to the material that they are being presented with and the outer margins would not receive any attention, by the bees, initially.

I started to make the master for moulding these test sheets on 15th Feb 2002. The dimensions that I have now finalised are:-

4.8,   5.0,   5.2,   5.4,   5.7,   6.0   There is still a good deal of work to do to finish this 'master' and then make the matrices to mould the final 'production' sheets.

The most meaningful results will be those that are obtained during the first few hours after insertion (this eliminates any possible 'learning').

How do we interpret the results?

My feelings are that the cellsize that is tackled most readily will indicate the cellsize to which that strain of bee being tested is currently conditioned to.

If more than one cellsize is drawn at equal rates... that would indicate a high degree of variability within the colony and may provide extra information in deciding on the race of a sample.

The test takes little time to perform, but the frames need preparing in advance. Some drawn patches may be kept for reference, but unused portions of wax can be recycled.

I hope this test will prove helpful to some of you.

Further Thoughts

If a shallow frame were prepared similarly, it could be placed in the 'top story' of an observation hive and progress monitored directly.

The width quoted is for use with B.S. Frames. The principle could be simply adapted to Langstroth frame types perhaps by making the cell groups five cells wide rather than four.

Supplies of Test Sheets

At this time (originally November 2000) no material is available as no one yet makes it. Over the winter I will be making a master sheet to make a press from, when this is finished I will make some sheets from it for my own testing. At December 2001... Little progress has been made on this project, but I still intend to carry it through, providing that I retain the degree of fitness that I currently have. The sheets will be available to other interested experimenters when I have made the master mould. (In progress 18 Feb 2002). (still not completed as of January 2005)

As these sheets contain much wax (I expect them to weigh as much as a sheet of brood foundation) I will have to make a minor charge for this... My motive is not profit, but my own rendered beeswax is a valuable resource to me. In any case it is not my intention to become a supplier of such sheets, but to provide samples for others to make their own presses.

The sheet is two repetitions of a pattern, so by cutting in half it will fit into half width frames that can be placed in mating nucs. (I will try this later)

I apologise for the disjointed text, but I thought I would leave some of the original material... In order to show the progression of the ideas.


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