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The Classroom

The Classroom – December 2023

- December 1, 2023 - Jamie Ellis - (excerpt)

The Classroom - ABJ - Jamie Ellis
Q  Queen cell and forced supersedure

 A few weeks ago, I grafted some queen cells. I wanted to get new queens mated before winter. A couple of days before the queens hatched, I put their cells into my hives. Have you had experience doing this? Do you know if this would be a good way to replace queens? I checked a week later, and it looked like they hatched successfully.

On another note, have you ever placed a protected queen cell in a drone-laying hive? Have you had success with a queen getting mated or does the drone-laying colony kill the virgin queen? I did not notice the hive was a drone layer when I added the queen cell and now it is torn down even though I wrapped it in aluminum foil.

Jeremy Patterson


For your first question: Are you asking if I have put queen cells into hives that had free-running queens? I have not tried this, but it is something that commercial beekeepers commonly do, with some success. Did your queens end up mating? Are they laying for you?

For your second question: Is this “drone-laying hive” a laying worker colony? If so, giving them queen cells likely will result in the cells being destroyed. Colonies that have laying workers “think” they are queenright; thus, they will stop most attempts at requeening them.

Jeremy’s reply:

First question: Yes. I did not find the queens. The hives are all doing well right now but since I did not mark the old queen ahead of time, I will [not] be able to tell [if the queen is the old queen or one that emerged from a cell I placed in the hive]. I guess if I do this again, I will mark the old queens.

Second question: I need to go check the hive again. I only saw that it was drone laying because it was majority drones and a lot of them were small. I found this out a week after I added the cell. If I had known it was mostly drones, I would have just put the cell in a different hive. I asked on Facebook and someone sent me a link for a study:


My follow-up answers:

First question: Thanks for the response. As mentioned, commercial beekeepers requeen this way frequently. It is cheaper for them to purchase/use queen cells to requeen their colonies than to purchase/use mated queens. They put cells into their colonies, sometimes thousands of colonies, and let the best queen win. They do this under the assumption that the newly emerged queen will be the one to win “most” of the time. I have never seen any data on the frequency of success this way. Next time you try this, it would be great if you marked your old queens before the introduction of queen cells. We might even try this method at the lab as you have piqued my interest. Either way, I know this is something some commercial beekeepers do frequently, so they seem to believe in it.

Second question: The paper you shared is quite interesting. I am surprised to see that requeening laying worker colonies with queen cells worked for colonies 60% of the time. I still prefer to requeen laying worker colonies with nucs (see this document: However, knowing about the queen cell success rate is useful/interesting.


Oxalic acid

 When doing an oxalic acid (OA) vaporization, how long does it take for the vaporized OA to do all it is going to do? I would think in 5 min after vaporizing, it has pretty much done its thing.

Stan Gore


Thanks for the question. You have probably seen me write that Dr. Cameron Jack is the resident OA expert at the University of Florida. Thus, I forwarded your question to him and here is his reply:

Are you asking about the amount of time it takes for the OA to vaporize? If so, that really depends on the device that you are using. If you mean for how long it takes for the OA to have an effect in the hive, then the answer is a little more complicated. Dr. Ellis is correct, that the label states to keep the hive shut for 10 minutes after vaporizing to keep the bees inside.

The OA vapor does two different things. 1) The OA settles on all the surfaces, ensuring that the mites will contact it, and 2) it causes the bees to groom themselves like crazy, knocking down a lot of mites in the process. We have measured elevated mite drop 72 hours after treatment, but I have not looked at mite drop incrementally after application, like measuring within hours after treatment how many mites continue to fall. Maybe the mite drop is all within the first 5 minutes or maybe it is spread out over 72 hours. I do not know, but that would be an interesting question to answer.


Milky spore and small hive beetles

 After reading Dr. Mangum’s June Past & Present article [“A Hive Cleanup in the Aftermath of Small Hive Beetles, Part 1″], I was wondering, would milky spore help control hive beetle larvae in the ground around beehives?

Tony Kissinger
October, Indiana



The short answer is that I could not find any research on this topic. However, I do want to offer a healthy dose of speculation here. First, milky spore is a disease of immature Japanese beetles caused by the bacterium Paenibacillus popilliae (same genus, different species, as the bacterium that causes American foulbrood). The products available using various milky spore formulations are all for the control of Japanese beetles. There is no reason to believe it would work against larval small hive beetles. Furthermore, the larvae would need to consume the spores, rather than crawl through them, as this is how the Japanese beetles are exposed to the treatment. This, then, would require application methods inside the hive, rather than simply on the soil around the hive. Ultimately, I suspect its known efficacy limited to Japanese beetles is what keeps scientists from looking at its possible impacts on small hive beetles.

Larger eggs laid in queen cells

The question about “Bee vs. breeder-reared queens” in the August 2023 “The Classroom” and again in the September 2023 and October 2023 columns raised some issues in my mind beyond your responses. The referenced study, “A Maternal Effect on Queen Production in Honeybees,” certainly suggests that there is more research needed into what you labeled “royal eggs”!

The questions I have are:

1. If the eggs laid into queen cells are larger because “queens may pause oviposition prior to laying in queen cells, since delaying oviposition causes bigger eggs with more yolk protein” (Zhi Jiang Zeng), then does the queen also pause before oviposition to lay a drone egg, since a larger egg with more yolk protein would also pass along more of her genetics to her son drones? That seems like a good way to better continue her genetics to future generations.

2. Could the same be true with the eggs she is laying in the fall to produce the winter bees? She has slowed down her egg production, so there should be more time between eggs for each to grow larger with more yolk protein before she oviposits into a worker cell. Again, these larger eggs would produce superior bees to survive the winter better.

3. Your September and October responses also suggest changes to the current thinking about queen quality. It seems to me that the highest-quality queens are swarm queens (a trait that beekeepers are trying to reduce), followed by emergency queens, simply because it is the nurse bees that decide which eggs to promote to queen status (here you should want the last cell capped since she is the youngest larva but also the last to emerge), and the lowest-quality queens are from those eggs chosen randomly by the grafter (sorry, queen industry).

From your statements in the October column, I see that many of your readers agree that the Zhi Jiang Zeng research paper opens a whole new area for honey bee research. I hope that we get a good response from the people doing that research, since improving the quality of queens and especially grafted queens is just as important as queens that produce bees that can survive with Varroa (and maybe Tropilaelaps).

Steve Winchell
October, Washington



Steve — Great questions. You have now progressed beyond what is known about this topic. Essentially, what we know is limited to data that show queens lay larger eggs into queen cells than into worker cells, and that this leads to multiple downstream effects on the quality of the resulting queen. We do not yet know how she makes larger eggs, or knows to produce larger eggs, for queen cells. Thus, the “pause oviposition” hypothesis offered by the article’s authors is speculation at this point, even if it turns out to be true.

There do not appear to be size differences between male and female eggs in honey bees (see: If a queen does pause before laying a drone egg, it does not seem to make that egg bigger than a female egg.

I would say anything is possible at this point. It is entirely possible that queens lay “larger” or “better” (however the latter is qualified/quantified) eggs when shifting to the production of winter bees. However, we can only speculate at this point.

Again, this is highly speculative. I can certainly see why you suggest this, but we just do not know. Certainly, folks reading the article you reference have speculated quite a bit about the quality of queens produced via the swarming process vs. the quality of queens produced via grafting. With the latter, we are just grabbing young larvae in worker-sized cells, implying that they originally derived from “smaller” eggs rather than larger ones that queens would have laid in a queen cell. But, we do not yet know if this is a bad thing, only that it may not be the ideal way to produce queens.

My point here is that everything you say may, in fact, be true. This idea might change how we rear queens. However, this is only a single paper, and the work needs to be replicated. Perhaps it is only true of the stock of bees the authors tested. Perhaps it is true only certain times of the year. Perhaps it is only true when colonies are fed, or during a honey flow. Right now, considerably more work is needed to get to the bottom of these and other related questions. The research and resulting publication were a fun introduction to this field. Now, we must wait to see where it all goes from here. I really do appreciate your comments and insight. I am always happy when I see beekeepers connect to research, especially how the research could improve the industry.

Carbon dioxide and bees

 At our bee association meeting, we were discussing hive ventilation vs. insulation during the winter months. Most of the members in this area are concerned with moisture condensing and dripping on the bees during the day, then freezing at night. To prevent moisture from condensing, they provide a ventilation hole at the top of the hive. The speaker was reading a paper where the author discussed the benefits of insulation and how ventilation not only let moisture escape but also heat and carbon dioxide, therefore causing the bees to work harder to maintain the heat in the cluster, and required them to consume more honey, thus reducing their energy supply. The author also stated that carbon dioxide expelled by the bees kept them in a dormant state, thus using less energy. I have also recently seen a company on Facebook promoting the use of carbon dioxide to manage Varroa. My question: Is there any truth to the benefits attributed to carbon dioxide?

Keith Anderson
October, Utah



I feel that “we need more research” has been a popular answer I have given today. Yes, the newer research suggests that ventilating hives over winter is not good for bees. This can lead to the buildup of moisture, loss of heat, consumption of food stores, etc. I have had great discussions about this topic with two individuals through our lab’s podcast: Two Bees in a Podcast ( In episodes 50 and 67, we interviewed Bill Hesbach (episode 50) and Derek Mitchell (episode 67) about insulating colonies in winter and summer respectively. Both make pretty compelling arguments, using data and the scientific literature, that hives should be insulated.

You are asking specifically about insulation in winter, so Bill would be a great expert for you in this regard. In fact, I have had Bill answer a few reader questions about winter insulation in recent installments of this article series., … .