Archive Special: HBHC Varroa Management Updates with Dr. Dewey Caron (S6, E11)

S6, E11 - Archive Special: HBHC Varroa Management Updates with Dr. Dewey Caron

Jeff Ott: Hey, everyone. Kim and I are out in the bee yards doing some much-needed work. We've selected this week's archive special for you from our 2022 talk with Dr. Dewey Caron regarding the 8th edition of the Honeybee Health Coalition Varroa Management Guide. This is the time of year you need to be on top of the varroa so your colonies are the strongest possible to get through the winter. Listen closely and treat your bees for varroa using the quality information in this management guide. Check out the show notes for links.

Also, later in September, we're talking with David Boito, author of the new book Bee Conspiracy. The book is a novel featuring a scientist and a cop who team up to investigate an unusual bee-related death that turns out to be connected to a much larger scheme. Now is your chance to order the book, read it, and send us questions to ask the author.

Okay, let's get on with today's Archive special. Welcome to Beekeeping Today Podcast, your source for beekeeping news, information, and entertainment presented by BetterBee. I'm Jeff Ott.

Kim Flottum: I'm Kim Flottum.

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Jeff: Thank you, Sherry. A quick shout-out to all of our sponsors whose support allows us to bring you this podcast each week without resorting to a fee-based subscription. We don't want that and we know you don't either. Be sure to check out all of our content on our website. There you can read up on our guests, read our blog on the various aspects and observations about beekeeping, search for download and listen to over 200 past episodes, read episode transcripts, leave comments and feedback on each show, and check on podcast specials from our sponsors. You can find it all at www.beekeepingtodaypodcast.com

Hey, everybody. Thanks again for joining us. We have a really good and a really important episode for you today. What is the number one problem you face with your colonies? Bad queens? Neighbors? Outyard locations? Wind? Maybe pesticides? Lack of forage? Man, the list of possibilities is long, isn't it? They are all problems at one time or another. I suggest your number one problem in your colonies right now are varroa mites. There are many people and organizations who've been working on this problem for the past 30 years. We've had several of them on our podcast.

The question is, who is synthesizing all of the data and making it readable, usable, by you and me? One organization is a nonprofit group of beekeepers growers, researchers, government agencies, agribusinesses, conservation groups, manufacturers, and consumer brands dedicated to improving the honeybee health. Who is this? They are the Honeybee Health Coalition. If you've been listening to the podcast, you know we've had guests on from the Coalition over the past five years. Today, we welcome Dr. Dewey Caron back to the podcast to talk about the latest and 8th release of the Coalition's Varroa Management Guide.

The guide really should be your management bible for dealing with varroa. You could go out and research it all yourself, do all the trial and error experiments on your bees to see what works, or you could read this guide instead. The Coalition reviewed the research data, took it out of the labs and the field studies, then summarized it down to which tools for which different management approach actually works. In fact, how do you know when to use which tool? It's like knowing when you should use a framing hammer and when you should use a tack hammer.

To drive this analogy into the ground, I will continue. Perhaps you don't want to use a big hammer, in our case, synthetic chemicals to treat for varroa. Maybe you still want to use a hammer, but maybe a smaller one, such as an organic chemical. Do you know when to use which? Is it the same in the spring as it is the fall?

The Honeybee Health Coalition has put this into a usable guide for you for free. Check out their Varroa Management Decision Tool and feel confident you are not experimenting with your bees. You are treating them using tested tools at the right time of the year.

All of that is coming up in our talk with Dewey about the Honeybee Health Coalition's updated Varroa Management Guide, but first, a quick word from our friends at Strong Microbials.

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Jeff: While you're at the Strong Microbial site, make sure you click on and subscribe to The Hive, their regular newsletter full of interesting beekeeping facts and product updates. Hey everybody, welcome back. Sitting across the virtual Zoom table right now is one of our most frequent guests. We love him here at Beekeeping Today podcast, Dr. Dewey Caron. Dewey, welcome back. I think this is about your fifth time on the podcast.

Dewey Caron: Yes, I think it is. Yes. Thank you. Good afternoon, wherever you are. Hello.

Kim: It's good to see you again Dewey. I just got to recommend just before we get started here. I have been using your new book, the book you and Larry Connor did, Honeybee Biology, and Beekeeping it's the third edition. It's the best one yet. If you haven't read it, folks get a copy. It's worth every penny and you will be a better beekeeper.

Dewey: Thanks, Kim. The third edition was a real labor of love. We revised everything. We went through every page and of course, it's completely updated. Added a couple of new chapters and it continues to be very popular before it's a teaching text for universities and colleges. Also for a lot a number of the clubs that are teaching a beekeeping course, and as a personal reference. People tell me they like it because they can find things and keep going back to it. Thank you appreciate it. Yes, thank you.

Jeff: Is it a book you keep by the bedside and read every day?

Dewey: Some keep it there by the bedside. We've added like 100 pages, so it's a perfect doorstop too, now as well.

Jeff: Well, no, no. I was just joking. It's a great reference and highly recommend it if someone's starting their bee book collection and or need to add one that is very valuable.

Kim: It's one of two books I turned to when I got a question about anything bees and beekeeping. It's Honeybee Biology and then the recent ABC. You put those two together and there's probably pretty much everything beekeeping in the world in there.

Dewey: Did you have a copy there, Kim, to show the people our new cover for the Honeybee Biology?

Kim: We'll put a cover on the web page, Dewey.

Dewey: I enjoyed it by the way, contributed to the ABC as well. That was a bit of a long drawn out this time because of publishing issues, whatever. That is substantial. Again, it's easy to find things in ABC.

Kim: Everything's laid out alphabetically. Even I can find things in it.

[laughter]

Dewey: Well, another new project that I've been working on is we have updated Honeybee Health Coalition tools for varroa management. We're now in our eighth edition which is incredible. Like with the revision of Honeybee Biology, we did everything. We went right back and looked at every word, every paragraph that we had in our eighth edition. Many people have downloaded an earlier edition or clubs have downloaded and put it on their site.

Very strongly recommend that people read, download it to their computer, or if clubs have done so to re-download it onto their club website. The eighth edition, Tools for Varroa Management from Honeybee Health Coalition.

Kim: I went so far, Jeff is to print it out. It's 37 pages long. It's not going to drain your paper or your ink and then you've got a copy in your toolbox that you can grab when you go to the bee yard.

Jeff: I want to talk about the Honeybee Health Coalition but I do wanted to go back. This reference guide, this varroa management guide is so valuable, that I think it's one of the references every beekeeper needs to refer to it and understand exactly what the industry is saying about the Varroa.

Dewey: It's been extensively vetted with the committee that we have. We expanded the committee this year, they are listed there. If you want to refer to it. I was responsible for the initial writing of it. As they say, we've gone through several revisions, so this is now eight revision, and we did. We looked at everything. We checked with the various manufacturers of the chemical compounds to be sure we had approved language. Because there's not only the label for some of these chemicals, but there's also a how to do it. They have their own brochures.

It is really a one-stop of where this information that we need to know is. It emphasizes the sampling as a method of knowing not just that you have mites but how many mites do you have, which gives us an element of risk.

We're indicating that now, we keep ratcheting down our recommendations in terms of how many mites is too many. Now, we're saying 1% to 2% is a level that we should try to achieve when we're doing a sampling of the adult bees. If it exceeds that, then you're into that element of risk, and the higher it becomes, greater than the 2%, the greater the risk.

Kim: Dewey, there's a lot about that I want to cover that you're doing this really well, but let me back up a half a step for people who aren't really familiar with the Honey Bee Health Coalition, how did you get started quickly, and then who's on it, and what are the projects are you working on?

Dewey: The Honey Bee Health Coalition is a gathering of folks from all aspects of what we call our industry. Certainly, there are beekeepers at some of the regional groups and national groups, a couple of local groups that are members. There is the industry that provides the pesticides, industry that supplies the supplies for beekeepers, but then a lot more than that.

It is also the industry that benefits from bees, the apple growers, and the sunflower growers, et cetera. They're on that and users. It is a group now that has grown to about 50 individuals.

We present our information by consensus. It is all science-based, so it's not just conjecture, or what people might be doing in terms of practices. We are organized as task forces. There's a task force around forage and nutrition, a task force around pest management. I'm on the beehive management task force, and that's the one that has developed these tools for varroa management.

We also have a quick guide so that if you answer our five quick questions in terms of your philosophy and where your bees are, you can then find the appropriate pages to go to with the tools for varroa management.

With our tools, we also did a recording of a dozen different videos so that, for example, if you've never used the Apivar, we have a short video, three to four minutes each of explaining how and demonstrating how you might use the Apivar strips as a varroa management tool.

Kim: You're not only telling me, you're showing me. Wow. For a learning device, that's exactly what you want. Your group, you meet regularly, or is this all virtual, or just how do you get your heads together?

Dewey: The pandemic has created some of those issues. We had been meeting two times a year, and during the pandemic skipped a couple of those meetings. We last met with the workshop in Michigan and our meetings are designed both to get us together, to talk about these various issues, collectively, and then as separating as our task force, to come under the separate task force.

When we identify our priority, for example, one of our last priorities was to identify that commercials do their Varroa management a little bit differently. How could we approach getting information to commercial beekeepers, those that have thousands of colonies. We came up with case studies of six different commercial individuals that discussed how they do Varroa, and how they are coping with this issue of the increasing developing resistance to the amitraz.

Amitraz is our only synthetic right now that we have available. We have the oils and we have acids as well, but this is the only synthetic we have. We're seeing that the bees are beginning to develop resistance to it. That's been the go-to, that's our gold standard, the one that is so effective. We developed the case studies, did the interviews with individuals, and have then developed that, and then are subdividing that, also do some visuals with them. We had some visitors do some commercial beekeeping operations here in Oregon, then Michigan, and then the Midwest.

Kim: I think all of this information, at least most of this information is available on your webpage. Is that correct?

Dewey: That's correct. Honey Bee Health Coalition, if you want to go specifically to the Varroa, then /Varroa, but simply honeybeecoalition.org then Varroa. Then you'll put that on the site, I'm sure.

Kim: Yes, that'll be there. Let's go back to, you started around, I'm looking at the management book here and you do some talking about varroa mite biology, basically, seasonal development, and that seasonal development thing is critical when it comes to treating. People need to understand what's going on inside the hive.

There isn't one treatment fits all and fits every time because things are different in the spring, summer, and fall. Expand on that just a little bit. If I take a look at this and I'm looking at the fall treatment schedule, and it's next, spring, what could go wrong?

Dewey: Yes. Well stated, Kim. It's certainly no one size fits all, and seasons are very different. In addition, we're trying to talk to beekeepers from various Southern Florida and up until Northern Canada. That is another of those variances. What we devised as a way to speak to all was to look at where your colony was in a seasonal development. We have a dormant period. Bees are not really dormant but they are at least inside their hive clustering. That's a very short time in Florida but obviously a much longer time in Canada.

What we might do with our varroa treatments at that time is very different than, for example, during the active season. We have a developing colony, we would call that spring, but spring is much earlier in Florida, obviously, than in Minnesota. Then a peak population where often most of our beekeepers will have super sun, and that in part dictates what you can use, and what you should be using and should be avoiding in terms of your use. With colonies piled with super, some of the management options are not as easy to do.

Finally, then the decreasing of population, that's not simply just bees losing bees, but it's also the bees growing the bees for the next season. We talk about the fall of the year as the beekeeper's new year or beginning of the year. What we do in terms of our colony care in the fall is to try to help the bees so they have sufficient population of sufficient age, and with sufficient fat bodies to survive the winter.

Obviously, this is a much tougher job for our beekeepers in our northern states and then Canada than it is for our beekeepers in California, Texas, and Florida. It is still an issue because there is a period of time when many colonies go broodless or very limited amount of brood. Yes, there's no one treatment that's going to work in all instances or all seasons.

Kim: What's the best way to sample my bees? Where am I going to get the best answer?

Dewey: The sample number is what we're pegging than your element of risk. You want to try to get an effective sample. We do recommend that you sample bees from the brood area or upfront the frame that is adjacent to the brood area. We recommend a sample of 300 adults. Some people, and sometimes a year, or for example, when there's less of a population, 200 will do, but 300 is a little bit more reliable sample.

Then we recommend that you then wash the mites from the bees using either alcohol. 95% is a little bit better than the 70%, but both will work, or a non-sudsing soap that will, again, do the same thing. We recommend swirling that, not shaking, protect them with the soap, you don't want to get all those bubbles going, swirling that.

We got to get a release of the mites, at the time of our collecting sample, that are in the segments, particularly the lower body segments of the abdomen of the worker bees, the mites that are actually actively feeding on the fat body of the bees. We want to get them separated. Then we have a sampling device so that the bees are held in a basket above the liquid so that as we swirl it, the mites are released from the adult bodies and swirl out from that 300 adult bees and then accumulate in the liquid at the bottom.

Many people like or prefer to use powdered sugar to do the same thing. It's not quite as easy to use and there is a chance that you will not get as clean a sample. In other words, a good sampling number. Now more recently, Avita Pharma has released a very popular collecting device that they've also modified so that you can use CO2 in terms of your material to release, get the mites to release from the bodies of the adult bees. That's our general recommendation.

We recommend sampling ahead of time so you know the number. Some individuals say, well, I know the number's going to be too high, so I'm going to go ahead and treat. That's perfectly okay, but if there is any treatment, we want to know, did it work? Has it been effective? The sampling post-treatment is also quite critical. Perhaps even more than that pre-treatment, particularly looking at the fall of the year, the declining population period.

Kim: Well, that makes perfect sense, that sampling, treating, and then sampling again to measure the effectiveness of the treatment. I'm probably guilty of that more often than I should be, is not getting back and doing that second sample. My assumption is that what I did worked, and that's probably not a good way to proceed, is that--

Dewey: Hopefully, it did work, but again, there can be a number of reasons why it did not work or did not work to the degree that you'd hope to do. One of the examples is some people will use oxalic acid, either vaporization or the dribble when there's a fair amount of brute in colonies. That does wash adult bees of their mites. If there's a fair amount of brew, the majority of the mites at that period of time are inside worker cells or drone cells if there's some reproducing. We don't get a very good estimate.

Many people have those modified bottom boards and have been using sticky boards with that. Actually, a fairly decent post-treatment estimation of how well your treatment work is to put the sticky board in and then, after your treatment, look at the number of mites. If that number is still too high, that says that I didn't get all of them, or I didn't get enough of them, or maybe something went wrong with the treatment, and I better do it again or try a different treatment.

Kim: Explaining for the sticky board is, I put it in before I treat, and I treat, and then I wait a period of time, and I put it in again.

Dewey: Yes. It's like at least two. Some people will also sometimes put it in when they're doing a treatment. If it's oxalic acid, for example, the treatment works for the first couple days so that it would have to be in that time. Some of the treatments have a delayed response. If you've used formic acid as your treatment, for example, and immediately at the end of the treatment period you put the sticky board in, you'll still get bees that are dying from the treatment itself. You'll look on your sticky board and say, gee, there are a lot of mites, but there should be because that's what the formic would do.

With a couple of treatments, we'd like to-- It's a little bit better to make a bit of a delay of a week before you then do your post-treatment analysis.

Kim: How do you interpret those numbers? I've got a five-story colony and I put a sticky board in, or I got a two-story colony and I put a sticky board in. What numbers should I be looking at before treatment? Maybe during, but certainly after treatment, what's the number that sets off the alarm?

Dewey: We have really no good science or consensus that will give you a good number to count, and so it's like a three-way decision. If you look at a sticky board and you don't see much in the way of mites, you really got to look before you see any mites. That's good. That's wait and do a sampling in another couple weeks. If you see mites and you start looking like it's like more than one every couple hours falling onto that sticky board, another words more than a dozen for a 24-hour period, that means maybe your mite number is high, particularly, if you got that big colony.

If you look at the sticky board and you see mites, God, geez, oh my god, there's a lot of mites. That means it didn't work, or you should see that during your treatment itself. If you see it before the treatment, you need to not delay in terms of trying to do a treatment.

Kim: Just a minute ago, you mentioned drones, and I know there are people who use integrated pest management and don't like to use chemicals, so they're using other techniques. If putting poison in a beehive is something that doesn't sit well with you, what can I do to monitor mites, A, and to, B, help control them without using a chemical?

Dewey: If you are of this mine, a number of our beekeepers are, A, for monitoring, the monitoring with powdered sugar is less harmful to the bees. You really need to shake them and dehydrate them. Unfortunately, when you then get them all powdered up and you put those bees back in, many of them won't survive, won't survive very long, but you will kill less as you do your sampling.

CO2, the same thing. If you have the right amount, if you over overdose the CO2, you'll kill a lot of them, but they'll then recover. That'd be an alternative to using the alcohol or the nonscented soap.

Now, B, treatment. In our tools for rural management, we do discuss integrated pest management at length. That means that you're not using the same chemical time after time after time, but it does also means that you're trying to use other methods, a technique management as a way to help control mites.

Particularly during the spring buildup, our major emphasis is to flatten the growth curve so that, one, there's not as many mites in a colony, and two, when they reach their peak population, they've not been as successful in reproduction. Some of this starts with the stock, bees that are greater, have greater high hygienic behavior, are more adept at finding the mites, reproducing in the cap cells and opening the cells, and then interrupting a mite reproduction. Now, adult female mites only have a limited number of eggs that they're able to produce.

A limited number of reproduction periods. If you interrupt any one of those, you have perhaps shortened her ability to reproduce herself by as much as 25%. On average, mite will reproduce up to four times on average. In other words, go into four cap cells and try to reproduce a daughter. When they go onto the drone cells, however, they're much more successful. Another technique is to manage drones.

This is how bee populations that don't have mite problems. The original host for the mite is an Asian bee, another species, and they manage the mites because they control when they rear drones. Our Africanized bee populations in the southern US do the same thing. They manage mites by managing when they produce drones, and they don't produce drones through the whole year like our European bee colonies will do. We can manage drones if we're not raising drones for mating. We can manage drones by drone brooded removal.

Then there are a number of good techniques to do this. You can purchase a drone foundation frame and insert that next to the brood area. My favorite way is in my standard-sized boxes, I put a medium-depth brooded frame. There's too much space below the bottom bar. There's that three to four inches. During spring buildup, the bees will more than likely fill in that space. They don't like the space themselves and will fill in that space with a sheet extending from the bottom bar that's drone cells. Drone brood removal has us wait until the drone cells are capped, and then we remove those drone cells from the colony at the cap stage.

Jeff: Hey, Dewey, hold that thought. I have a question for you, but we need to hear from one of our sponsors.

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Jeff: Kim, I'm just thinking about Dewey's a medium frame in a deep in the springtime and all that drone brood, is that what you harvest and then you put in a frying pan and eat?

Kim: You can. Actually, drone brood isn't bad. Actually, you got to catch them a little bit earlier than sealed, or at least I like them a little bit. They start getting tough, and they start forming cuticle and whatever, but I'll tell you who really likes that drone brood are my chickens. I'll just take that chunk of wax if I'm using a short frame or I'll take the whole frame, and I'll throw it in the chicken coop. I built a thing that the frame can stand upright in. There's a dozen chickens on both sides of that frame fighting over their drone food, so they benefit, and I have a good time watching so.

Jeff: I can't think of anything worse than someone saying I got a piece of lettuce or broccoli in my teeth and someone pointing out, "Hey, you got a brol in your teeth, so that's so sorry [crosstalk]

Dewey: In addition to chickens, if you don't have chickens, if you hang up that comb, by the way, there are a number of birds that also will eat the meat and like insects. Boy, they'll come and really have a feast on it.

Jeff: That's a great idea. That is a really good idea.

Kim: Well, Dewey, what other techniques of integrated pest management can I employ if I don't want to put poison in my beehive?

Jeff: Let me go back to the screen bottom board real quick. It raises a question because currently in the last several years there's been the thought of returning to a more natural approach to a bee environment, the beehive and log hive is often used as an example. The concern about the screen bottom board providing too much air and too much ventilation to the bees, is there any way to satisfy the desire to be a more natural environment for the bees and this IPM approach?

Dewey: Very definitely. I do surveys out here in the Pacific Northwest of our beekeepers in the Oregon, Washington, and Idaho. One of the questions I have is screenboard use and fully 75% of the individuals indicate they are using a screen bottom board replacing the solid, but then also during the winter period, you close or at least partially close off that screen bottom board. Then I key that to results in terms of survivability. I do it by losses, but the other part of that number is survivable.

Indeed, those that do close or partially close the screen bottom board during the winter do enjoy an increased percentage of survivability of their counties. One of our issues in the bee tree, there's a very small entrance. The bees have narrowed the entrance by propolis, and so there's very small entrance of new fresh air into the colony. If we think of that screen bottom board, that's all that air entering the colony not just at our entrance, at our entry board, but also from the bottom. Yes, it does improve survivability at least here for our bees that we survive in a survey in a Pacific Northwest, by closing or partially closing that open screen during the winter period.

Kim, you were asking about some other treatments. Our initial season, as the bees are building up, is we want to try to work at flattening that curve. Bee stock, citing colonies, how close the colonies are, and ensuring that bees have a distinctive address, in other words, different painted colors or something above the entry board, that is something that they can recognize and each of them being very different. Then doing dividing of colonies if too strong. Not only to control swarming but in addition to helping then you can do some different types of mite treatments.

As the numbers build up, we're often looking at some chemical intervention. For example, in the beginning, to help flatten the curve, we find that the essential oils, the time oil products Apiguard and ApiLife Var, are pretty effective at helping reduce the number of mites that are successful in their reproduction.

During the time that we have supers on, and for some of us for very early flows, for example, that's pretty darn early in the season. You're trying to get locust bloom flow in the East. You're trying to get bigleaf maple flow out here in the Pacific Northwest. You've got to get those supers on even in March, and many of the years to be able to catch that bloom. That limits the types of other chemical interventions that we might be able to use and then gives the mites an advantage to be able to build up.

About all we can use during that time is formic, and unfortunately, if we use formic, we often will have collateral damage of killing queens or stopping the queen from laying eggs. We have to be very careful on that application.

We can return to chemicals after the supers come off. This is when doing a pre-treatment sample is most advantageous. If you do a pre-treatment sample once the supers are off, so this would be at peak numbers or maybe beginning of the decrease of colonies, what we'd call the fall. The numbers are high, and that would be saying that they're above this 2%. You want to get the numbers down quickly so the bees have a chance to rear those fall bees. About the best treatment at that time is formic acid.

The Formic Pro is designed to cause less of that collateral damage, and you can according to the label use a half treatment, so that you don't have to put a full treatment on particularly the smaller colonies, but on all your colonies. That will bring the numbers down pretty quickly. Then to try to help the bees rear those fall bees that are going to get through winter at that point the synthetic, the Apivar, the strips, will work pretty good. They have to go in for about a week period of time.

Now, if your numbers persist being high in the fall, in other words decreasing population, at that point, some people will use oxalic acid either vaporization or will use it as a dribble, or will use Formic Pro for a second period of time. That is permitted. Then hopefully, your numbers are down.

Over the winter period, once the brood has decreased, naturally has decreased in colonies, some colonies never go broodless, but is is very limited, then a very useful tool at that point is oxalic acid either as vaporization or as a dribble.

Now, if you wait until the bees are very tightly clustered, so it's a very cold day in the later fall below 50 degrees, the bees are going to be in a cluster inside of their colony. In other words, they're going to form into that cluster, and the outer part of that cluster is bees that are like an umbrella. If you put the dribble on that, it just runs right off the bodies of that cluster of bees. That's why vaporization is a preferred method for oxalic acid, but it's harmful for us as well.

You've got to have acid-proof respirator yourself, gloves, long sleeves, long pants. Also, we do recommend eyewear when you use all of that when you use vaporization and certainly don't get in a situation where you're breathing in the vapors that develop once you cook your crystals into the gas form.

Kim: That sounds complicated. I know a lot of people that use it, and they like it because it does what you just said it does, but tough to do, tougher than the other ones.

Dewey: The analogy I give all of these are tools that we can use. If you wanted to put a nail in a piece of wood, you could use a screwdriver, you could use pliers, but a hammer does an awful lot better job of putting the nail in the wood. With our tools for varroa, the drone brood removal works in the spring when the bees want to raise drones. Doesn't work in a fall because they're not in that same behavior of raising drones in a fall. You feed them, yes, heavily feed them. You can make them raise drones into the fall but they're not normally wanting to do that.

Too with our tools and oxalic is a perfect example. Oxalic acid is a very, very good tool for washing the mites off of adult bee bodies, but it is no good for those mites that are reproducing. If you've got a brood, a lot of brood in a colony, it is only getting a fairly small portion of the varroa mites in your colony, so it's a good tool. Good tool when there is a less amount of brood. It's not a good tool there at peak population or when your colony is growing so strongly in the spring.

Jeff: Well, that makes perfect sense. For our listeners who are still struggling with an approach or a management style to deal with varroa is the Honeybee Health Coalition's varroa treatment decision tool. That's a fantastic tool. I've directed multiple beekeepers to help them decide what type of approach they want with their treatment modality, the time of year, and the population dynamics of their colonies is which tool to use at that particular time. It's really good at giving you options. It's a great resource.

Dewey: Our Honeybee Health Coalition has, if you go to just to the coalition and look at varroa, we have both the management tool, the quick decision tool, and best management practice as well. We also have this case studies in terms of the commercial beekeepers and how commercial beekeepers are approaching their role management, which is different as the commercial beekeepers. That's their livelihood so they cannot allow the mites to get ahead of their colonies.

One of the things we emphasize in our tools for varroa management is you need to manage them with an integrated approach through the season. It is very difficult once the numbers of mites get elevated in a colony to bring that number back down. You want to keep it from getting up to a level where it's going to cause all of this harm.

Kim: Dewey, all of this is on your webpage, and a lot more that we talked about, and I certainly encourage people to go to the webpage to look at the videos to download the management. What's the message we've missed that you want to share? What's the one thing most important, I think?

Dewey: That last point I think I made is that we've got to manage the mites. We can't let them get ahead of us. There is no one tool, no one technique that does it best. We need to think in terms of integration. Manage that curve so that it never grows very large and so our colonies have a chance to stay healthy.

Stress colonies will have a greater difficulty trying to manage their varroa mites so it's not just for all mindset that are our issue here. That it's some other things as well, forage, decreasing forage , decreasing ability to find good, safe spots for location of colonies so they have enough forge to get those resources that they need.

Of course, we still have issues in some locations with the internal gut parasite Nosema, and the spring buildup, we have the issue with the bacterial disease of European foulbrood. It's a multifaceted approach using our best management practices so that we can help the bees. We'd love to keep them the way they keep themselves and tree hollows naturally, but it's not the way we're going to manage bees. We've got to join their battle. We just can't put them in a box, leave them, and say, "Good luck, bees," because, it's just they're not going to have a great deal of luck, particularly with varroa.

Jeff: Again, it's been an honor having you on the show. Look forward to having you back and further this discussion. There's so many different avenues we could go down, especially on treating Varroa, but everything else that you've touched on, so look forward to having you back.

Dewey: Thank you, Jeff, thank you. Thank you, Kim, appreciate the opportunity to join every year. Hope you have a good overwintering period. Many of you'll view this now during the fall and over the wintering period.

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Dewey: Your bees come out strong and healthy, and that what we didn't capture this year with a surplus honey we get next year.

Kim: Okay [laughs]. Good. Thanks, Dewey.

Jeff: Thank you, Dewey. I'm glad we had Dewey on this whole varroa topic. I don't think we can talk about it enough. I know it's been said too many times but maybe not enough. If you have honeybees, you're managing two critters, the honeybee and the varroa.

Kim: Yes, that goes without saying, and I think this new management book goes a long way and giving beekeepers not only more tools but better ways to use the tools that we've already got. I want to back up one-half step and say something about the Honeybee Health Coalition itself. The fact that this group of people coming from every angle that you can come at in agriculture and sitting down at a table and talking to each other without throwing things is a pretty amazing feat. I hope this industry appreciates what that group is doing and what they're accomplishing to help all of us.

Jeff: I have directed so many beekeepers to the Honeybee Health Coalition website. The information that's available there and the tools available to beekeepers are far superior than anything else that you'll find. I'll pick on YouTube, then you'll find on YouTube, it's vetted, it's real information, and you can trust what you read. We only talked about the varroa management but they do everything else, and there's so much out there.

Well, I'm looking forward to the next version of everything that Dewey and the Honeybee Health Coalition puts out.

Kim: Yes, they do a good job and we're lucky to have them.

Jeff: That about wraps it up for this episode. Before we go, I want to encourage our listeners to rate us five stars on Apple Podcast or wherever you download and stream the show. Even better, write a review and let other beekeepers looking for a new podcast know what you like. You can get there directly from our website by clicking on the reviews along the top of any webpage.

We want to thank our regular episode sponsors, Global Patties, Strong Microbials, and especially Betterbee for their longtime support of this podcast. Thanks to Northern Bee Books for their generous support. Finally, and most importantly, we want to thank you, the Beekeeping Today Podcast listener, for joining us on this show. Feel free to leave us question or comments, and leave a comment section under each episode on the website. We'd love to hear from you. Thanks a lot, everybody.

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