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To improve the cluster, destroy the nest

Recently, someone asked if I had read the article in Bee Culture (November 2011, Volume 139, Issue 11, p. 63) about removing the center of the brood nest to make room for the cluster and, if so, did I have an opinion. Truth is, I had missed this little gem or I would have written about it sooner. And do I have an opinion? Hmm, let me think . . .

Because I’m rarely so testy—at least in print—let me cut to the “my opinion” part first. I will be subtle: Short of issuing foragers personal bPads at taxpayer expense, this is the most hare-brained scheme I have ever encountered.

The author of the article seems to think that the entire overwintering problem is the fault of the Langstroth hive and its parallel frames. He believes that bees cannot form a proper cluster because all the frames get in the way. So, in his infinite wisdom, he created a big hollow in the center of his brood nest so the bees could make a true and solid cluster. The diagram shown in Bee Culture looks something like the one below.

This cut-away diagram shows the frames removed to provide a cluster space for the bees. From “Overwintering: New Ideas From Old Books,” <em>Bee Culture</em>, November 2011.
This cut-away diagram shows the frames removed to provide a cluster space for the bees. From “Overwintering: New Ideas From Old Books,” Bee Culture, November 2011.

In his argument the author ignores that fact that Langstroth hives—and most other hives as well—are modeled after wild hives. He discounts the fact that bees have been making parallel combs that slice through the brood nest since long before mankind crawled out of the ocean with his power tools.

The first question that came to my mind was, “How will the cluster support itself?” Unless it is filled with helium, I don’t see how it can levitate itself into position so it can maintain a “true cluster” in the void.

But the bigger problem is this: the part he cut out is the part where the brood is supposed to be. The bees’ idea was that the brood nest—the nursery, if you will—is supposed to be in the warmest, most protected spot in the entire hive. If you cut the supporting comb away, where will they put the brood? And where will the nurse bees put their little rocking chairs? Brood is not held in its mother’s arms like human babies or carried around in a pouch like a kangaroo. Honey bee brood goes in honey bee combs.

And the timing of this destruction couldn’t be worse. According to The ABC & XYZ of Bee Culture (41st edition, p. 831), “the least amount of brood rearing in colonies occurs in the fall months of October and November and normal brood rearing starts in December and increases greatly during the cold months of January through March.”

This method excises the brood nest combs just before the bees start the arduous task of winter brood rearing, and right when it is most difficult for the bees to replace the comb he just took out. How can they rebuild the brood nest when it is too cold for them to leave the cluster? And since they don’t secrete much wax this time of year, they have to tear down other comb and rebuild it in the proper place. Removing the brood nest like this is nothing short of cruel.

According to honey bee researcher Jürgen Tautz in The Buzz About Bees (p. 157), “The comb of the bee nest is in a sense a part of the bees themselves. . . . The nest is not only living space, food store, and nursery, but also an integral part of the superorganism: skeleton, sensory organ, nervous system, memory store, and immune system.” Eviscerating the brood nest is akin to stripping bees of their very “beeness.”

The author himself admits problems: “In some hives . . . the bees had built burr comb down from the shorter frames and had begun raising brood in it . . . In others there was a mish-mash of comb in part of the open space.” Well, of course there was.

I can see why someone could have a hard time visualizing a cluster with planes of parallel comb passing through it. And it’s even harder to imagine the clustered bees smoothly rotating their positions when the combs are blocking their way. But just because he can’t visualize it doesn’t mean he should change it. The system has been working for millennia. The bees are okay with it—so should be this author.

Rusty
HoneyBeeSuite

In this foundationless frame, the bees built a passage to the other side. This helps them rotate through the winter cluster. Flickr photo by <a href="http://www.flickr.com/photos/emmajane">ejhogbin</a>.
In this foundationless frame, the bees built a passage to the other side. This helps them rotate through the winter cluster. Flickr photo by ejhogbin.

Mite management in large hives

I have been asked to explain why I believe large colonies make winter mite management easier. It’s important to note that I said easier and not easy. You still have to pay attention and you still have to do something.

It is interesting to me that people who prefer triple-deep hives frequently report successful mite management, and people who have not tried them claim that triples are mite factories. In my own case, I had been successfully overwintering 80 to 100 percent of my hives for many years until last year, when I switched from ApiLife Var to HopGuard. I “misinterpreted” the instructions, treated all my hives in the same insufficient way, and ended up losing most colonies to mites. I just happened to have a few triples in that group, and oddly enough, it was the triples that survived despite huge mite loads.

Okay, my story is merely anecdotal, but it piqued my curiosity. I began asking others about their experience with triples and heard many similar stories. I also did a lot of reading about the population dynamics of both mites and bees. So I will explain my theory but, alas, it is only a theory.

First, I agree that triples are mite factories but only because more bees produce more mites. For most of the year, mites/bee is no different in small colonies than in big ones. There is a maximum mite/bee ratio that can be reached before the colony just collapses—big or small.

The timing of mite treatments

Mite treatments have to be performed at the right time regardless of hive size. That time is when brood production is lowest, usually late summer or early fall depending on where you live. A small number of brood cells provide few places for the mites to breed, so most of them are riding around on the backs of bees. These adult mites are exposed to the mite treatment and are killed by it.

Some colonies have virtually no brood for a short period before fall build up, so if you can time your treatments right, you can get about a 95% kill rate. Some mites will survive, of course, and others will ride into the hive on visiting bees, but for the moment at least you have very few mites.

Hygienic behavior plays a part

All bees have some hygienic behavior, and bees can and do rid themselves of some adult mites and even pull infected brood out of cells and dispose of them. If you have two colonies—one small and one large—and both have nearly zero brood for that brief period—the large colony will have many fewer mites/bee than the small one. This gives the large hive a distinct advantage. Although both hives will experience an increase in mites subsequent to the treatment, the large colony has more bees to deal with each individual mite as they go into winter.

Although a large colony has a larger brood nest than a small colony, large colonies tend to have a smaller proportion of brood to adult bees. This is probably due to the fact that the colony is so large—enough bees to keep warm, enough bees to defend the hive, enough bees for hive duties, and certainly enough mouths to feed—that there is no compelling reason to make it larger or even to keep it as large. If the number of brood cells per adult bee stays low for an extended period, the winter cluster is in a better position to keep mite numbers down using only standard amounts of hygienic behavior. No matter what the task, large colonies nearly always out-perform small ones.

Can mites drown in a gene pool?

Related to this is simple genetics. A large population has a bigger pool of genetic traits, so in a large colony there is a greater probability that there are some bees that can successfully deal with mites. Remember that although the bees in a colony have the same mother, they have a variety of fathers, so there can be quite a bit of genetic variation. More bees mean more genetic variation and a higher probability that some bees will have good hygienic behavior.

During the winter neither small nor large hives have drone brood, which means mite built-up over winter is slower than in spring and summer. The reduced rate of mite build up allows the larger colony to maintain its advantage over the smaller one until colony expansion and drone production begin in the spring.

The ratio is key

Once spring expansion begins, however, the large colony will produce mites like crazy—lots of brood and especially lots of drones. If left alone at this time, mites will begin to overwhelm the colony. But by this time, the large colony can be split, re-queened, treated, or whatever the beekeeper prefers. The point is, the colony m­ade it through the winter because of a high bee to mite ratio at the critical time.

In this scenario, it is always the ratios at specific times of year that are important, never the specific numbers. The ratio of mites to bees and the ratio of bees to brood during the fall and winter are what tip the balance in favor of the large colony surviving until spring.

Rusty
HoneyBeeSuite

What’s an unlimited brood nest?

The “unlimited brood nest” is one of those beekeeping concepts that sounds way more complicated than it is. I don’t know if willful obfuscation results from beekeepers trying to confuse each other—or just the rest of the world—but it seems to be a favorite pastime.

So what is it? An unlimited brood nest is one where the queen’s movement is not restricted. Basically, if you use a queen excluder, the queen is confined to an area on one side of it. Since the queen can’t lay where she can’t go, you end up with a limited brood nest. It’s that simple. Conversely, if you lose the excluder, the queen can go anywhere she wants—she has an unlimited brood nest. Elementary, eh?

Some people call a triple deep brood box topped with an excluder “unlimited” but I beg to differ. Either the queen’s movements are restricted or they’re not. In fact, queens rarely extend their nests over more than three deeps—but that’s beside the point. If you’re using an excluder you are not allowing for an unlimited brood nest.

The purpose of an excluder (or a limited nest) is to keep the queen from laying eggs in the extracting supers. But an unlimited nest has many benefits for the bees, including more winter stores and better insulation (see “More on triple deep hives“). So many beekeepers entice the queen to stretch her nest ever higher.

One of the ways to cajole the queen higher is called “pyramiding”—another big word for a small concept. Pyramiding is simply taking a few frames of brood from one box (usually from the outer edges of the nest) and centering them in a box above the main nest. This encourages the queen to lay further up. Since she already has brood there anyway, why not? It changes the nest shape from a wide sphere to a pyramid (more or less).

Pyramiding is similar to checkerboarding except that with pyramiding you are rearranging the brood nest—with checkerboarding you are not. Pyramiding is almost indistinguishable from opening the brood nest except that the purpose of pyramiding is to make the nest taller, whereas the purpose of opening the brood nest is to prevent swarming. Opening the brood nest makes the nest wider and it may make it taller, depending on how many frames of brood you have and where you put them.

All these concepts are closely related and overlapping, so confusion is inevitable. For optimum swarm and brood nest management, it helps to understand the basics of backfilling, checkerboarding, opening the brood nest, unlimited brood nesting, and pyramiding. Trust me, the concepts are easy. It’s just the terminology that’s difficult.

Rusty
HoneyBeeSuite

What is a brood pattern?

Experienced beekeepers frequently talk about brood pattern. But what is a brood pattern and how do you tell a good one from a bad one?

A brood pattern is nothing more than the place where the queen laid her eggs. Simply put, the brood pattern is the shape of the brood nest. The queen lays her eggs altogether in a group, and the group has a characteristic shape that we call the brood pattern. It is easiest to see when the brood are capped with wax, but an experienced beekeeper can see the pattern even when the brood are in the egg or larval stage.

The capped brood are usually in the center of the frames, and since the cluster is more or less spherical, so is the brood nest. On cold days or nights, the cluster of bees is able to keep all the brood warm since the brood pattern mimics the shape of the cluster.

When you look at one frame you are seeing a slice of the brood nest. Think of a round loaf of bread. If you cut it in parallel slices, the pieces on the outside are smallest. As you get closer to the center of the loaf, the slices get larger and larger. After the largest slice, they begin to get smaller again.

It is the same with your brood pattern. The frames on the edges will have less brood than the frames on the middle, and the very biggest will be in the center. The bees usually store a layer of pollen around the brood nest, and above the pollen–and perhaps to the side of it–they store honey. Drone brood is often found along the bottom or the sides of the worker brood.

A slice (frame) taken from the center of the nest is often described as a rainbow–a layered arc consisting of brood, pollen, and honey. The nest is not always dead center in the middle of the hive, but it may be. Photos of good brood patterns are often so perfect that the beginning beekeeper thinks something is wrong with his bees. I’ve included a photo below that shows a pattern that you’re more likely to see–good, but not picture perfect.

Another important aspect of brood pattern relates to the number of empty cells. Some empty cells are normal and may even be used to warm the brood. But the brood cells should not be random or scattered; cappings should be uniformly brown or tan and not sunken. Too many holes in the pattern may indicate an old or failing queen, or they may indicate disease, or they may indicate a colony not large enough to care for all the brood. It is for these reasons that beekeepers use the overall look of the brood pattern as a measure of colony health.

The photo below shows a foundationless frame, not completely drawn out. The brood nest is skewed toward the front of the hive, but you can see that the pattern is solid with only a few empties. Pollen is stored in the uncapped cells on the perimeter of the brood nest and honey is stored in the upper corners. At the bottom of the brood nest is a spattering of drone cells. Although this frame doesn’t have a textbook pattern, it is obviously from a thriving colony. With a little practice, you will be able to identify a good pattern when you see one.

Rusty
HoneyBeeSuite

Brood pattern on a foundationless frame. Flickr photo by Maja Dumat.
Brood pattern on a foundationless frame. Flickr photo by Maja Dumat.

Reversing brood boxes: is it necessary?

In the last couple years I have been re-thinking my position on the spring reversal of brood boxes. If you are not familiar with this maneuver, it means switching the position of the brood boxes such that you move the brood nest to the lowest point in the hive. Several reasons are often given for reversing, but most often you will hear that it prevents swarming by giving the bees a place above the brood nest to store their honey.

Over the years I have become more and more successful with my bees. I attribute much of this success to one thing: I disturb the brood nest as little as possible. Now—before I take any action that will disturb the nest—I ask myself, “Is it really necessary?” Yes, there are times when you must disrupt the nest, but there are many times when you can make the choice not to.

The theory of reversing comes from the idea that a colony of honey bees will only move upward, it will not move downward. But if you look beyond the circle of Langstroth beekeepers, you will find many who don’t buy into this idea.

For example:

  • Bees in a hollow tree build brood comb downward. The comb is attached at the top of the hollow and successive layers of comb are built beneath that.
  • Warré beekeepers, imitating the natural propensity of bees, put their new brood boxes under the colony, and the bees fill them up.
  • Top-bar beekeepers don’t add brood boxes to the top or the bottom, but the bees do just fine by moving sideways into new areas.

I felt really vindicated yesterday when I read an article in the February 2011 Bee Culture by Larry Connor. He writes, “Experience has shown me that most colonies will reverse themselves as the season progresses, moving into the top of the lower box and growing downward.” You see, I knew it!

The misunderstanding comes because all winter long we watch the bees move upward towards the honey supply, so we start thinking bees always move upward. But they don’t. In the spring and summer as the nest is expanding the bees will move down, just as Warré beekeepers have always known.

In his article, Larry Connor goes on to say that you can reverse the hive bodies as long as the entire brood nest is in one box. This way, you don’t end up splitting the nest in pieces. I agree with that, but the problem is that the nest almost always straddles more than one box. So why bother?

In the past, I always reversed my boxes. I have killed queens doing it, totally riled up my colonies doing it, starved portions of the nest doing it, and even dropped a whole box doing it. Last year, I only reversed three before I decided it was a needless incursion into the brood nest. All the colonies eventually moved into the lower boxes by themselves. This year I won’t reverse any.

Based on my experience last year, the colonies that were not reversed expanded into the lower box as soon as the weather warmed. When the nectar flow began, I added honey supers. These colonies showed no more propensity to swarm than any of my colonies in previous years.

I get the feeling that reversing is one of those things we do because we always did it before, not because it has any clear and compelling benefit. In fact, I think it may do more harm than good.

Rusty