Can you have too many dummy boards? Well, obviously you can, but having made half a dozen last winter and another three last night I’ve yet to suffer from an excess of them. In fact, I’m going to have to make some more this weekend.
Dummy boards …
I’ve run out of dummy boards this year for three reasons. Firstly, I’m using the Demaree method for swarm control much more and so have two brood boxes to control free space in (and I usually remove frames of stores in the top box). Secondly, I’ve been using three frame nucs for queen mating, some of which are in five frame nuc boxes. Finally, with several swarms captured in bait hives, my colony count has increased.
Dummy boards are brood-frame-sized (length and height, but not thickness) pieces of something, with a simple top bar. The something is probably ideally a nice piece of red cedar about a centimetre thick. However, all mine are 9mm plywood from the offcuts bin in my local timber merchant, or stuff I’ve recovered by dumpster diving during refurbishments at work (I have no shame). I cut a piece 355 mm x 205 mm and simply glue and nail a top bar from 9mm stripwood along the longest, straightest edge.
Eleven frames plus dummy board …
I’ve seen all sorts of designs on the web. Some made from a Correx-lined standard brood frame, some with side spacers and some with insulation. Although there is a case to fill a large amount of excess space with something like an insulated fat dummy (e.g. when housing a nuc-sized colony in a full brood box) most of the time a dummy board will simply be occupying a small strip of space that would otherwise be filled with brace comb. Typically this is when you have eleven brood frames in a National-sized box. When new, you can squeeze a dozen frames in. However, as soon as there’s some propolis it gets nearly impossible to add or remove the last frame without rolling bees. In this case it’s better to use eleven frames and a dummy board.
Spacers and any other embellishments seem totally superfluous to me. If there’s space for a full frame I’ll use a full frame, so why purchase a full frame dummy board lined with Correx? If I want the dummy board to be a certain distance from the adjacent frame I’ll put it there … and in a couple of hours the bees will have propolised it into place. Finally, if you use poly nucs, or have roofing felt on the roofs of adjacent hives in the apiary, a dummy board makes a great place to stand the smoker when not in use during inspections (from experience I can confirm that neither poly nor roofing felt appreciates exposure to a hot smoker 🙁 ).
Note: After writing this I checked the price of dummy boards with major beekeeping equipment suppliers (I’m thinking of writing about beekeeping economics in the winter) and was horrified to see that they varied between £5.75 and £6.12. Dummy boards are the perfect example of something that is well worth making … even more so because the most expensive one is plastic, so would melt under my smoker 😉
The oil seed reap (OSR) and hawthorn have finished here and there’s very little forage available for colonies. To make matters worse the weather has been changeable, restricting the time available for colonies to forage. Small colonies, such as casts that have been attracted to bait hives, have lacked sufficient numbers of foragers to store any nectar and have needed feeding. Small, weak, nucleus colonies have starved unless supplemented with syrup. In contrast, large swarms have fared much better – it’s almost as if there’s some sort of size threshold below which the colony isn’t able to cope with adverse conditions.
This poor weather has caused significant problems for queen rearing.
Virgin queens are taking ages to get mated, far longer than happens in settled weather. Many of the days have had warm, clear mornings, but with thunderclouds building up around lunchtime leading to a deluge in the afternoon – the peak time for queen mating. Many mating hives have gone queenless over the last fortnight.
Without a significant flow, getting cells started – at least in the queenright queen rearing system I use (the Ben Harden method) – means the colony must be fed syrup for the few days between adding the grafted larvae to the cell raising colony and the 9th day (after egg laying) when the cells are sealed.
There’s not much that can be done about improving the chances of getting queens mated, other than ensuring a supply of freshly emerged virgin queens ready to take advantage of any suitable breaks in the weather. After more than three weeks in a 2-3 frame nucleus I’m usually pessimistic about the chances of getting the queen successfully mated.
In contrast, with relatively little effort you can feed syrup to the cell raising colony, thereby ensuring the larvae are given the best chance of success. If the cell raising colony has supers on I temporarily remove them to another hive to prevent the bees simply storing syrup in with nectar.
Remove the supers …
In practice the easiest way to achieve this is to set up the queenright cell raiser the day before grafting (as described in detail previously) with a clearer board on top of the upper brood box, beneath the supers. When you come to add the grafted larvae, first remove the supers which are now cleared of bees and put them aside, gently slide the cell bar frame between the frame of unsealed larvae and pollen, add 150-200ml or 1:1 w/v (thin) syrup to either a fat dummy feeder or frame feeder in the upper brood box, then put the crownboard and roof back. Add the removed supers to other strong colonies in the apiary.
3 day old QCs …
Unless the weather dramatically improves I then check the colony daily, adding a further 150-200ml of thin syrup to the feeder. This just takes a few minutes and results in minimum disruption … a quick waft of smoke at the entrance, the same amount through a slight gap beneath the raised corner of the crownboard and then gently remove the crownboard. The day after grafting I check the larvae to see how many have been accepted. There’s no need to check the cells on the next 3 days (despite the picture shown here), simply add a bit more syrup to the feeder. On the fifth day after grafting the cells should be sealed and there is no longer any need to continue feeding. In addition to preventing tainting the honey supers with syrup, removing the supers also concentrates bees into the brood boxes.
With any queen rearing it is critical to be aware of the timetable. Eggs are laid, hatch on day three, grafted on day 4, queen cells are sealed on day 9 and the virgin queens emerge on day 16. There’s not much variation around these timings; if you graft a larva that is too old it will still be sealed into the cell on day 9 (after the egg was laid), but will have had less opportunity to feed well and so may generate a sub-standard (‘scrub’) queen. If you thought the larva was 18-24 hours old, but it was actually 48-60 hours old, it will emerge up to a day and a half before you expect it to.
Oops … too late
This is “not a good thing” as the newly emerged virgin will run amok through the colony destroying all the other queen cells which will then be partly or completely torn down. Alternatively, if all of the larvae are a little older than you thought they’ll all emerge and have a melee in the upper brood box of your colony setup for Ben Harden queen rearing. If you’re really unlucky an undersized virgin will squeeze through the queen excluder and slaughter your mated, laying, queen in the bottom box. All of this can be avoided by understanding the timing of events involved in queen development and keeping good records.
Tom’s Tables …
BIBBA provide a copy of Tom Robinson’s table, essentially a queen rearing diary in Excel format. It’s designed for using Jenter or Cupkit systems, rather than grafting, but the underlying development timetable – the dates when the cells are sealed and when the queen emerges – are of course identical. I’ve modified a copy to suit my own queen rearing programme, using grafting and mini-nucs. By simply entering the grafting date, the remainder of the timetable is automagically completed, so there should be no reason to miss one of the critical dates. In the same way that good records are required to select stock to graft from, you should keep a record of both the queen rearing activity and the performance of the resulting queens.
Getting the timing right
How can you avoid early-emerging queens? Pretty easily in practice, as long as you do the following:
Check them finally 24-48 hours before expected emergence. By this time the sealed cell may show signs of being crowned – a sort of thin darkened ring around the tip of the cell which is a good indication that emergence is going to happen shortly.
Cage the cells in a hair roller to trap any virgin queens that emerge earlier than expected (you can do this anytime after they’re sealed).
Use the cells before the queen emerges.
Keep good records and remember that queen development is unaffected by the vagaries of the weather or your social diary … graft young larvae and use the resulting queen cells 10 days later.
Looking after grafted larvae
With a little practice a success rate of at least 80% should be achievable when grafting. As described previously, you can easy tell whether the grafting has worked by examining the cell cups about 24 hours later. You’re looking for a 3-4mm relatively smooth, slightly curved wax rim added to the cell. It’s very thin and fragile at this stage. Accepted grafts will also be covered with workers building the cells and feeding the larvae – you may not be able to see the spigot or cell cup at all. Gently move these bees aside if necessary (don’t shake or brush them off) with your finger. It’s actually possible to determine whether the larvae are accepted as little as a couple of hours after grafting but I usually prefer not to disturb the colony again (and often graft late afternoon, so it’s usually getting too late in the day).
Ben Harden cell raiser …
Assuming the cell raising colony is wells stocked with bees I rearrange the boxes at this first inspection so that the Ben Harden brood box is on the top of the stack. The main reason to do this is to save your back. Only do it if there are ample bees in the colony; you do not want the cells to get chilled by placing them over a couple of near-empty supers. In a strong colony, I’ve had three or four supers separating the queenright bottom brood box and the cell raising brood box. In the picture (right) the hive nearest the camera is a Ben Harden cell raising colony. There are three near-full supers between the lower and upper (BH setup) brood box. In addition, since the OSR is nearly over and the stores are capped, I’ve moved one full super over a clearer board above the upper brood box, emptying it ready for extraction.
Fat dummy …
The next few days are critical. The larvae need to be well fed and the cells need to be drawn out fully. If there’s no flow the cells may be ignored. To prevent this feed a small amount of thin syrup (1:1 w/v) in a frame feeder in the upper box. This is where a fat dummy with an integrated feeder is useful. Arrange this so that the feeder is next to one of the two pollen frames and add about 100-150ml of syrup daily until the cells are sealed. You barely need to disturb the colony to do this … a waft of smoke, lift or slide aside the crown board, add the syrup and close up again. There’s no need to check the cells, the frame of unsealed brood or the bottom box (we’ll come back to these two shortly).
If there is a good flow it is not necessary to feed the colony. Since this is essentially a standard production colony (with an additional upper brood box) the bees should continue to store nectar in the supers.
Are they sealed?
Brace comb and sealed cells
Five days after grafting the cells should be sealed or about to be sealed. The cells will by now be reasonably well sculpted, with a characteristic pitted appearance. The exception is the cell tip which will be pale smooth wax. When checking the cells don’t shake or jolt the cell bar frame and don’t keep the cells out of the colony longer than necessary. Once sealed the colony no longer needs feeding. In a good flow the bees are likely to build brace comb in spaces on the cell bar frame and to fill this with nectar.
Knock ’em off …
Queens emerge on day 16 (counting from the day the eggs were laid), about twelve days after grafting. This is sufficient time for the colony to swarm, so you must continue with your standard weekly inspections. Simply lift off the upper brood box, gently put it down on an adjacent hive roof, or the upturned roof of the queen rearing colony. Remove the supers if present. Remove the queen excluder, check the bottom box for queen cells in the normal way, then reassemble. Do not forget to put the queen excluder back (or the newly sealed cells will all be torn down). You must also check the frame of unsealed brood in the upper box as they may be making queen cells on it. If so knock them all off. You only need to do this once as there should be no young larvae left once your grafted larvae are in sealed cells.
Two frame nuc box
If there are queen cells in the bottom box (but they haven’t swarmed) I make up a small nuc with the queen, a small amount of brood and a frame of stores in a two frame nucleus box. I then knock all of the queen cells back. If they generate more they’ll be well behind your own grafted larvae. That being the case, use one of the sealed grafted cells to requeen the colony. If the bottom box swarm it’s not a major problem as long as there are enough bees left to keep the grafted cells warm and well fed. If you want to use other swarm control measures remember that the cell raiser has done its job now … you can remove the sealed cells and place them in a suitable incubator until you use them for requeening (just before or after emergence).
Caging the cells
The advantage of the Nicot Cupkit system is that push-fit “hair roller” cages are available to protect the cells and to prevent an early emerging queen from destroying the rest of your hard work. These can be added soon after the cell is sealed, but I usually leave them a few extra days during which time the workers provide all the care the cells need. During this period they will usually sculpt the cell extensively. The only problem is if they build lots of brace comb between cells before you get a chance to fit the cage. If they do, a little gentle surgery with a sharp knife should be sufficient to trim them down to fit into the cage. Don’t force things. You don’t want to squeeze or crush the developing queen.
Using the cells
You should use the cells about 10 days after grafting, which gives you sufficient leeway should a queen emerge a little early. They can be added to mini-nucs, 2-5 frame nuc colonies or full colonies … all of which will be covered in the future.
The ‘Ben Harden’ method is an approach used to raise queen cells in a queenright colony. It offers a number of advantages that make it particularly suitable for relatively small-scale beekeepers, for beekeepers who want only a limited number of queens (10’s rather than 100’s, though the latter is possible if well organised) or for beekeepers who are taking their first steps in queen rearing. Consequently, it is also suitable for using within an association during queen rearing courses.
The advantages include:
it requires only a limited amount of additional equipment, including a spare brood box and two overwidth “fat dummies“
it uses honey production colonies in a way that has little or no impact on foraging, and hence nectar collection
it uses a queenright colony which does not need to be “boiling with bees” and which is both easier and more pleasant to handle
it requires only limited manipulations of the colony
The general principles of this approach are straightforward and are reasonably well described by the late Dave Cushman modified from an article by Ben Harden in Bee Improvement (the BIBBA magazine). Further information is available in A simple method of raising queen cells written by Ben Harden (#59 in the Beekeeping in a Nutshell series available from Northern Bee Books).
This is the first in a short series of posts covering the basics of queen rearing using the Ben Harden queenright method. Each post covers one of the key stages in the method, which are:
It is possible to use this method to raise queens if you start with a single colony, using it as a source of larvae, the cell raising colony and the colony used to harvest nurse bees for populating the mini-nucs from which the virgin queens will be mated. This is not really recommended … at the very least you need a range of colonies to judge and choose the best as the donor for the larvae.
It is a also very good method to use in associations running queen rearing courses. Individuals taking part prepare a colony for cell raising, grafting is done communally using good stock and cells are distributed 24 hours after grafting.
The ‘Ben Harden’ queenright queen rearing method uses a double brood box in which much of the space in the top box (above the queen excluder) is filled with oversize dummy frames. These have the effect of forcing bees in the top box to be concentrated on the frames containing young larvae and, critically, the grafted larvae in the cell bar frame.
Correx and tape
Normally the frame containing the grafts is accompanied by a frame of unsealed brood and two frames containing ample levels of pollen. The fat dummies that flank these occupy the remainder of the box and therefore each need to be the thickness of three and a half frames (i.e. 133 mm). They can be built from pretty much anything convenient – thin plywood around a softwood frame or Correx held together with duct tape work equally well.
To make them slightly more useful they can be filled with expanded polystyrene chips. They can then be used to ‘dummy down’ a weak colony in a standard brood box for the winter, effectively converting it to a four-frame nuc (assuming two are used) without having too much dead space for the bees to keep warm. If there is no flow grafted larvae will usually be ignored. To avoid this it is necessary to simulate a flow by feeding with thin syrup. It is therefore useful to build at least one fat dummy with an integrated frame feeder. Dave Cushman describes construction of fat dummies with a very narrow feeder, negating a requirement for a wooden float. Mine are wider, about 20mm, because that was the size wood I had at the time … I’ve not had problems with them being a bee graveyard.