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Sept. 20, 2021

Seasonal Pollens and Nutrition Research with Dr. Gloria DeGrandi-Hoffman (S4, E14)

Seasonal Pollens and Nutrition Research with Dr. Gloria DeGrandi-Hoffman  (S4, E14)

Today we talk with Dr. Gloria DeGrandi-Hoffman. Gloria is the Research Leader at the Carl Hayden Bee Research Center in Tucson, Arizona. Gloria and the researchers there are involved in several projects, but today we talked to her about just two that...

GloriaToday we talk with Dr. Gloria DeGrandi-Hoffman. Gloria is the Research Leader at the Carl Hayden Bee Research Center in Tucson, Arizona.

Gloria and the researchers there are involved in several projects, but today we talked to her about just two that are both new and promising for beekeepers and their bees.

Modeling honey bee nutrition requirements on a seasonal basis is an area that has not received much attention to date, as they have been for many other animals. It turns out that the pollens that bees collect satisfy those requirements on a seasonal basis. High energy in spring with large amounts of amines and fatty acids for brood rearing, less so in summer and more towards storage use in the fall for overwintering. This may affect pollen feeding, and pollen substitute formulas to optimize their diets at the right time.

But there are both seasonal and regional differences in pollen quality, and what is being noted is that with climate change affecting the phenology of blooming dates, bees may not be able to get the food they need when they need it.

Another project being studied is overwintering colonies in climate-controlled buildings. They are looking at how much food will a colony need to do this, what the population should be when they enter a building, and when should they come out of storage so that they are ready to build fast for early pollination work, or later for honey flows. In addition, they are researching the best time for a season’s mite controls to be placed for optimum control and honey bee health.

Along with this they looked at cost efficiencies relative to winter losses, feed costs, colony strength and labor and made some interesting finds relative to these costs.

Listen in to hear more about this exciting research!

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S4, E14 – Seasonal Pollens and Nutritional Research with Dr. Gloria DeGrandi-Hoffman

Jeff Ott: Welcome to Beekeeping Today Podcast presented by Bee Culture. Beekeeping Today Podcast is your source for beekeeping news, information, and entertainment. I'm Jeff Ott.

Kim Flottum: I'm Kim Flottum.

Introduction: Hey, Jeff and Kim. Today's sponsor is Global Patties. They're a family-operated business that manufactures protein supplement patties for honey bees. It's a good time to think about honey bee nutrition. Feeding your hives protein supplement patties will ensure that they produce strong and healthy colonies by increasing brood production and overall honey flow. Now is a great time to consider what type of patty is right for your area and your honey bees.

Global offers a variety of standard patties as well as custom patties to meet your needs. No matter where you are, Global is ready to serve you out of their manufacturing plants in Airdrie, Alberta, and in Butte, Montana, or from distribution depots across the continent. Visit them today at

Jeff: Hey, thanks a lot Global Patties. You know each week we get to talk about how much we appreciate our sponsor support and you know we'd rather get right to talking about beekeeping. However, our super sponsors are critical to help making all of this happen. From the hosting fees, software, hardware, microphones, recorders, you name it, they actually enable each episode. With that, thanks to Bee Culture magazine for continuing their presenting sponsorship of this podcast. Bee Culture has been the magazine for American beekeeping since 1873. Subscribe to Bee Culture today.

We also want to thank 2 Million Blossoms that sponsored this episode. 2 Million Blossoms is a quarterly magazine dedicated to protecting all pollinators. Check it out at and that is with a number 2. Check out the new 2 Million Blossoms The Podcast also available for the 2 Million Blossomswebsite and from where we download and stream your shows.

Hey, everybody. Thanks a lot for joining us. We're truly happy you're here. Hey, Kim. Happy end of September.

Kim: Yes, it's the end of September. I can see winter from here. The goldenrod is pretty much wrapped up this season. I could still smell it a little bit, but it's going away and it's dark by 8:00 at night. It's getting there.

Jeff: I'm afraid it is. You're starting your winter preparations, getting your bees all set for the winter?

Kim: I'm just starting the process this week. We'll see how well they did on goldenrod and start taking mite counts.

Jeff: It's definitely an important time of year to get your mite counts and do any treatments before you put them to bed for the winter. Hey, On Honey Bee Obscura, you and Jim are talking about winter prep.

Kim: We got another one coming up on feeding, what to feed, how much to feed, when to feed, when do you quit feeding, what do you feed, all those things. Over the years, we've had a lot of experience and we've made a lot of mistakes. We'll share both with you.

Jeff: Oh, good. I'm looking forward to it and that's really timely too seasonal-wise, and also in line with our podcast, Beekeeping Today Podcast, because we are smack dab in the middle of a series of podcasts on honey bee nutrition and feed. Last week, we had Pete Berthelsen here from the Honey Bee Health Coalition and Bee and Butterfly Fund talking about honey bee forage and importance of that. Today, we have Gloria DeGrandi-Hoffman who's from the USDA Tucson lab talking about seasonal pollens.

Kim: Interestingly, it's something that people haven't looked at much for honey bees. A lot of other animals, they looked at seasonal availability of food and how nutritional requirements change over the season from spring to fall. She's doing some interesting things with bees on there.

Jeff: It's pretty amazing. I'm looking forward to talking with her in just a few short minutes. To continue our nutritional topics next week, we are talking to Dave Aston about his recently released book, Good Nutrition, Good Bees. It's a deep dive into everything you ever wanted to know about honey bee nutrition. Stay tuned, folks. Kim, some disappointing news coming out of Bee Culture. The Ohio Bee Conference has been postponed.

Kim: For a year.

Jeff: For a year.

Kim: They're pushing it back to next year. They had speakers who had to cancel and they had people who'd sign up were canceling. Traveling is an iffy adventure anytime, but when you put on an airplane with as much adventure as there is riding in an airplane anymore, you put all those together and Jerry made I think a good choice in postponing it.

Jeff: Ohio's a bit of a hotbed they say of COVID.

Kim: Yes, it is, this year.

Jeff: That's too bad. That's a shame. All right. We'll look for additional news on that as the months progress. Folks, we do now have transcripts available of each episode. If you have a chance to, if you hear something, you want to learn more about it, or you weren't quite sure what was said, you can go look at the transcript and pick up any special words or authors or titles or weird names that we might have said. They're pretty useful, aren't they?

Kim: They're pretty good. I'm impressed. The quality, I've read a few of them and they're spot on. If you're going to use them, you can be pretty confident that what you read is what you'll hear.

Jeff: Absolutely. They do a fantastic job. They remove all the ums and uhs and stuttering that I do. I actually read intelligently on the transcripts.

Kim: I was surprised.

Jeff: Wait. What?

Kim: [chuckles]

Jeff: [chuckles] All right. Let's take that opportunity to segue right into our discussion about seasonal pollens with Dr. Gloria DeGrandi-Hoffman. First, a quick word from our friends at Strong Microbials. I'll get you, Kim. I'll get you for that.

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Jeff: Hey, while you're at the Strong Microbial site, make sure you click on and subscribe to The Hive, Strong Microbial's regular newsletter full of product information and beekeeping facts. Hey, everybody. Welcome back to Beekeeping Today Podcast. Sitting across the virtual Zoom table from us right now is Dr. Gloria DeGrandi-Hoffman. Did I get that right, Gloria?

Dr. Gloria DeGrandi-Hoffman: Yes.

Jeff: Good. Thank you. Thanks for joining us.

Gloria: Pleasure to be here. Thank you for the privilege of being on your show.

Kim: Gloria, it's good to see you again. It's been a while since we've had a chance to chat. Just for background, Gloria is a research leader at USDA-ARS honey bee research lab in Tucson, Arizona. Just for a little background, Gloria, how long have you been there and what do you do?

Jeff: [chuckles]

Gloria: Okay, Kim. I've been there quite a while. I was hired there after finishing my Ph.D. at Michigan State University. I did a postdoc for a little while and then was offered a position at the Tucson bee lab. That was back in 1985. I've been there ever since I got the position. They wanted to hire a mathematical modeler to build models to predict yields and things like almonds. We also did apples and we did a lot of pollination work.

Then Africanized bees came in. I did Africanized bee work and built population models as to why Africanization was happening. I built colony models, then Varroa happened, built Varroa models. These models were all built to direct the research efforts to create a conceptual framework for conducting research and for generating hypotheses that you could see where the testing of these hypotheses fit into a bigger picture, a bigger system, as to why various phenomena would occur.

For example, how could African bees come into an area that was settled by European bees, that was predominantly European, and over course of time become the predominant genotype in the population? That's so rare in nature. That doesn't happen, but it happened here. It has happened everywhere that African bees had migrated. We don't model some guts and testable hypotheses and feel like we can now explain why that happens and this all centers around the Queens in developing times and lots of other behaviors of African bees.

Now I work in nutrition and cold storage of overwintering colonies. I've always built models to drive the research that we do. I hope that's not too long-winded, Kim, but I have been there for a while, buddy. What can I say?


Kim: That's exactly right. One of the things that caught my attention here just a little bit ago was the work that you did on the seasonal production of pollens that bees collect and what it means to their nutrition. Tell me about that because when I read this summary, I have to say, this is one of those blinding flashes of common sense that you had, that just explained a whole lot of things. What was it you found?

Gloria: Again, thinking about the populations in colonies and looking at it through modeling, you really see how that population changes throughout the year and how much brood the bees have to rear to get them to have a large enough population so that they'll survive the winter. This population is changing in age and in structure throughout the year. I guess it came to me when I was hiking. It was in the springtime and we were seeing elk and so forth and started thinking about what they were eating then compared to what they were eating. We were hiking the same place in the fall.

I started thinking, they ate different things, is the nutrition different? So, I started looking into the wildlife literature to see if anybody else was thinking about seasonal nutritional requirements that matched the animal's behavior, and it was all over the wildlife literature. Everybody was thinking that way. That's when we decided, well, it may apply to honey bees as well, so we went out and tested that, and are still working on that.

Kim: When I read that, like I said, it was one of those blinding flashes and the first thing that came to my mind was what bears eat and in the spring when they have young ones, they are eating high energy food and then the fat. In the fall, when they're getting ready to hibernate, they're eating fat foods, nuts, those sorts of things, and it just fell into place. Well, of course, bees are the same thing. How can a beekeeper use that information?

Gloria: I think that if you have the luxury and you can trap pollen, when I stored it, you know that if it was spring pollen or summer pollens or fall pollens and keep it separate, and if you want to build up a colony in the spring, feed them nice spring pollen because it has amino acids in it and fatty acids in it that can stimulate hypopharyngeal gland development, brood rearing, and if you want to feed it back in the fall, get fall pollens and it just matching the nutrition to where the colony is in terms of what its nutritional needs might be.

Kim: That was really fascinating. That makes perfect sense. One of my questions to get more beekeepers to trap pollen, it's good free food and now you can make it even better I think if you start categorizing when you caught it and then when you feed it back, so good job. [chuckles] I'm impressed. Like I said, it was one of those common sense things, but once you saw, you go, "Well, of course."

Jeff: Well, that was really interesting because I'm thinking about, does that change regionally, I wonder? Because some areas have more of a pollen flow in the fall than they do in the spring and finding that balance would be challenging. Collecting pollen, I guess, would be a challenge and not starving a hive. I'm thinking selfishly about the Pacific Northwest or at least my area where right now everything's dry and there's almost no pollen coming in. I'd be hesitant to collect pollen, but anyways, I love this topic. It's wonderful.

Gloria: We did do a regional study, the last one that we did and that we published on, we had pollen from Iowa and pollen from Arizona. We chose those two areas because of the differences in the overwintering and the differences even in the colony cycle. We found spring pollens from Iowa and spring pollens from Arizona had those amino acids that you needed to build populations, but what was interesting is those ones from Iowa had higher levels of Omega3 fatty acids to them.

They generated larger hypopharyngeal glands and they were mostly clover pollen, and so we thought it really spoke to the importance of having clover out there for bees because you can really build colonies. It really has the nutrients for building in the spring.

Kim: Along those lines, did you check on the dandelion because the common belief is dandelions are so important in the springtime. Did you check on the pollen quality of those?

Gloria: We didn't pick up any dandelion in our samples, unfortunately. We do a lot of nutritional analysis at our lab and it's only a matter of time before we get the dandelion pollen in there. We don't have it so much in our area in Arizona.

Kim: I can see an entrepreneurial beekeeper here right now, the wheels are turning in and thinking, "Well, I've got nothing but clover where my bees are, why aren't I collecting as much of that as I can and making it available to beekeepers who don't have clover pollen in the spring?" I'm guessing that even if you're feeding supplements, you can add some of these spring pollens to your supplement and enhance them that way so we wouldn't need to make all of your food, just a little bit of it, but every little bit helps.

Gloria: Yes.

Kim: I like this. [chuckles] There you go beekeepers another way to make some money doing this. Well, Gloria, what have we missed on the pollen thing because I know you've done some work on overwintering storage and I'd like to get to that too.

Gloria: Well, I guess that if you can get your bees on natural pollen and you can find places where that's going to be available to you, that's going to go a long way to solving problems that you may have in your colonies, but if it's not possible, like you're saying, Kim, just having even a little bit of pollen coming in makes a huge difference.

Kim: There you go, Jeff.

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Jeff: We may get to this in a little bit and we can wait till then. What is the climate change? I'm thinking about pollen and the change in the environment and everything's either too much rain or not enough rain. Are you looking at how the climate change is going to affect the pollen in different regions?

Gloria: Oh, yes. That's an area that we're just getting into right now and have been working on only for this past year's climate changes. If you are going to put an umbrella over the problems that we have keeping colonies alive, that umbrella would be climate change. The reason that I'm saying that is in these areas where we're having these high temperatures, it disrupts flowering, it disrupts the phenology of the flowers, it could possibly disrupt the nutritional value of pollen and reduce the amounts of nectar. These are all researchable topics. If you have drought along with it, then you don't even have flowers.

There's been, with the warming climate, a mismatch between bees and plants that they forge, and just as an example is the timing of plants such as goldenrod when it comes out now is a bit earlier than it used to be and the bees are forging on it, flying, and not getting into the hive for overwintering in the state of confinement, but the temperature is still warm enough for them to fly sometimes on into November. Not only they consuming those stores that came out early, but they're also aging and corrupting that age structure in the colony that they need to get them through spring dwindling the following spring. There's a whole host of challenges with maintaining colonies in this changing climate.

Jeff: Yikes.

Kim: Oh.


Kim: That sums it up nicely I think. [chuckles] I'm just going to segue right over there and that leads into the wintering work that you're doing in enclosed buildings. I can see where climate change is even going to affect that, but how are you studying overwintering in buildings? What are you looking for?

Gloria: The first question that we ask when it came to overwintering in cold storage buildings was, is this economically feasible for beekeepers? We did a study where we work with a commercial beekeeper, Harvest Honey, and they were fabulous cooperators, collaborators on this in that they shared with us what their expenses were and how much it cost to, for example, feed a colony, to move colonies from almonds to Texas, from Texas to North Dakota, from North Dakota to Idaho. Just that whole route. How much does all that cost?

At the end of the day, where do our profit margins when we're getting a payoff with almonds. What we found is that the expenses were considerably less when you put colonies in cold storage because you were feeding them all winter long. That was the real saving. What you were paying is a rental fee for cold storage per colony, which is a little bit more than what it would cost transportation, labor, and materials for a single feeding, pollen and syrup.

Kim: Did those reduced winter losses enter into that factor at all?

Gloria: That's the next thing because the first year, we did not do a great job of picking the colonies that we put into cold storage. We just put colonies into cold storage, and we didn't, I would say, have great success in pulling them out and having colonies at the size that you could wait for almond pollination, but it's all a numbers game. We had a lot of colonies and a lot of numbers and we were able to construct a little model that had to do with how big your colony was when it went into cold storage. No, I'm sorry. How large that colony was back in September. How many mites it had per hundred bees back there in September.

We found they were the best predictors as to what the probability of that colony was going to be larger than four frames or six frames or eight frames. We built a model where you can put whatever number of frames you wanted, that it would generate those probabilities, and that model is on our website, so any beekeeper can use it. Anyway. When we were more selective in the next year of the colonies we put in, we almost had 90% success, and I think we can even do better.

We put the colonies in earlier. We put them in October, and it was our models that predicted that as well. We predicted it based on the latitudes we were in in North Dakota. Because this is when egg laying should end. This is when you have nothing but sealed brood left in the colony, that's when you put it into cold storage. When we took them out in middle of January, I believe it was, they were down in almonds with brood in those colonies. I think to tell you the truth because there wasn't much the beekeeper had to feed the colony, so that's you're spending money, I think we could've left them in cold storage a little longer, and taken them out a little later.

Now, what the logistics would be for that in terms of getting them to the almonds when they came into bloom, but they were sitting in the fields for several weeks before we had almond bloom, so that's the next question. Can we leave them into cold storage for longer and save some money?

Kim: You're leaving, instead of January, you're pushing it towards the end of January. Then you're getting the right time because they're going to bloom tomorrow, that close. What was the population going into cold storage for these colonies, and what was the population coming out of cold storage such that you could take them and put them in almonds right now?

Gloria: I'm just going to talk about the colony if you put it in in October because they were our best ones. They were eight to ten frames when we put them into cold storage. They came out somewhere between four to six frames of adult bees and brood when we took them out. They continue to build throughout almond bloom. The colonies reported in November went through the spring dwindling while they were on the backside of almond bloom and then started to grow from there.

The ones we put in in October, that spring dwindling flattened out. Those colonies came out of almonds as large as they were when they went into almonds. I want to say, they were I should say six to eight frames because our averages were the high eights. When it came to our colony sizes in March and they were different than our colony sizes in January. Yes, we were up around eight framers.

Kim: Of course, you should be happy with eight frames, I would think.

Gloria: Yes. They were rearing brood all the pollen from the almonds. What we were the happiest about is that we were able to smooth out that spring dwindling, which is what makes or breaks colonies. Spring dwindling flattened and so those colonies just took off and enable the beekeeper to make splits coming out of almonds, and that's always a good thing.

Kim: You weren't feeding at all when they were in this cold storage?

Gloria: No. They were fed before they went into cold storage.

Kim: They go in, and then they sit for some amount of time. Then they come out, and then they get pushed. The day you take them out, are they getting fed then?

Gloria: They feed them then, yes, because there's nothing out there. Yes, they open them up and they're flying and they're rearing brood. If you don't want to break in that bridge cycle, and you don't want to break in that bridge cycle because I say it's a numbers game. You want them rearing as much brood as possible. There's new bees coming out to replace the ones that were born the previous fall, and will be out there forging almonds and dropping off the population.

Kim: Yes. We've talked to John Miller, he's also doing this, and one of the things that he brought up was the amount of dead bees in that storage building accumulating over the winter. Did you see that when you put them in in October?

Gloria: When we put them in, we never were back in that the storage buildings are closed. They got on the truck in January, so I can't comment on that. I'm not sure.

Jeff: I just want to mention that our conversation with John Miller on indoor wintering was back in March. I think season 3 episode 43. If our listeners want to go back and listen to that discussion how John built his indoor facility and the considerations he has for that.

Kim: And his timing was different, so I was wondering if there would be a difference in how they got through the winter and what they were like when they came out. It's interesting to know. Yes, take a look at John's because it's different, and it's interesting to notice the difference. The facility that you were working in you said was rented? It wasn't owned by the beekeeper?

Gloria: No. It was a facility that was in Idaho, so the beekeeper paid by the colony to winter their bees there.

Kim: I'm guessing that the people who owned the facility were doing a very good job of monitoring all of the environmental factors, the CO2, the ventilation, the temperature, and the light, and all of those things?

Gloria: I would assume so. If you want return customers, it's best not to kill their bees.

Kim: Good point, yes.

Gloria: I can understand the hesitancy of beekeepers in terms of adopting this management strategy, and talking with beekeepers and working with them, they go slow. They still overwinter some outside or with their traditional means of overwintering and then put a portion into cold storage just to sort of a walkthrough, a test, and everything, and it's probably best, but I think that we'll get better and better with cold storage, developing recommendations for it.

One thing that we learned was we also had a set of colonies that came from a Southern latitude and we put those in cold storage in November and they did not do well at all. That brought up the question of the formation of winter bees and whether winter bees get made in Southern latitudes and what kind of management practices would you need if you were in a Southern latitude and wanted to overwinter colonies in cold storage.

Kim: You need to be feeding them some of that fall pollen you were collecting earlier-


Kim: -to have them get ready as to their diet. Well, you just brought it up, is there a standardized reference that says the building should be this cold? You should have light like this, you should have CO2 in parts per million. Is that defined pretty well yet?

Gloria: It might be. I'm not familiar with what those definitions are that I could tell you what they were. I know it's dark in there the entire time, and once they close it, they close it and there's air exchange, and it's 40 degrees in there and it's 40 degrees 24 hours a day.

Kim: Yes. Well, that makes sense, you'd want it steady rather than fluctuating up and down. One of the things that John mentioned was the colonies were open and bees that went out to do a potty run, couldn't find their way back because it was dark, it was red light actually, and they couldn't see in the red light. There's that, but that makes keeping inside of the colony clean a lot easier, I suppose.


Gloria: Well, it's interesting that they would come out if the temperature held at 40.

Jeff: I think it was a little bit warmer, but I'd have to go back, or a little, yes, I think he was just under 50 degrees, wouldn't they? I can't--

Kim: I don't remember.

Gloria: That may have accounted for some of the-- We have a cold storage facility at the lab now, and we'll be putting bees in it for the first time this fall, and we're going to keep it at 40. I'll have to look and see if we've got dead bees on the floor.

Kim: You'd spent a lot of time sweeping. I wonder on the cold storage part, what did we miss, Gloria?

Gloria: Well I think that when you put colonies into cold storage is going to depend on the latitude that your bees are housed, where their apiaries are going into the fall and the best recommendation is when you know that the queen has stopped laying and all you have in your colony is sealed brood for your latitude, that's probably the best time to put them into cold storage. I also think that as we move forward with the change in climate and a warming climate, it's going to be more difficult to overwinter colonies successfully because of these warmer fall temperatures and sometimes warmer winter temperatures.

They cause that cluster to break and the bees to fly and age and make that spring dwindling dip that much deeper. Also, I got interested in cold storage originally because of mite migration and that the best way to stop mites from migrating into your colony on foragers is to get them into cold storage as always.

Kim: I know you made the model that you put on your webpage. I went and took a look at it, and the mites per 100 bees is if not at the top of the list, very close to the top of the list of being the thing you want to pay attention to the most.

Gloria: Yes, absolutely and you got to do it by September.

Kim: The old theory that winter starts in August, we may have to push that back to winter starts in July.


Kim: So that in September we are at where we want to be with mite population because now, people, at least in our latitude up north here, are looking at, "I want MY mite population in September going into October because I've still got--" Well, pay attention, Jeff, winter starts in July.

Jeff: I'm sitting here thinking just from my perspective because we never really get to a hard freeze in the Pacific Northwest, so our winter schedule is not the same as your winter schedule in Ohio, Kim. I'm trying to, for beekeepers around in a temperate area, temperate climate, they're going to have to do some of their own homework and not just go based on what somebody in Ohio is doing.

Kim: Well, I'm thinking, it sounds like Gloria, that if you're in a place like Jeff is, in the Southern third of the US, where you don't have a hard winter. The colder you can give them the earlier in the year, the better off they'll be. Does that make sense?

Gloria: Yes. The sooner they stopped flying in the fall because that cuts down on migration, cuts down on the aging of the last brood cycles, and burning of the fuels that they collected in the fall, fall pollens, so yes.

Kim: Jeff, you're going to be looking at getting them cold sooner.

Jeff: [laughs]

Kim: And keeping them cold.

Jeff: I'll go to Costco and get that big freezer.


Jeff: Because our average temperature here is maybe in the 40s. It might dip down to 20 sometimes at night, but mostly, it's in the 40s and you can see them flying pretty much all the time, so it's interesting. It's a challenge for all beekeepers, no matter where you're located for sure.

Kim: It'll be fun figuring it out. Good luck.


Kim: Well, Gloria, we've covered fat pollen in the fall and energy pollen in the spring and winter bees and buildings. This has been a lot of fun and it was good seeing you again, it's been a long time, it had been too long.

Gloria: Yes. Hopefully, not too long, we'll be able to start seeing each other in person again, but this is a real good substitute, and I sure appreciate you guys inviting me on your show.

Kim: Well, it's been fun. Jeff, you got anything else?

Jeff: Well, the only thing I was going to ask is, Gloria, if there was anything that we hadn't talked about or anything that's new since you've released the work on the seasonal pollens that you'd like to bring to the attention of our listeners?

Gloria: No, I think we've shifted over now to looking at climate change effects on bees and on those pollen nutrients and seeing how they may change depending upon the landscape where they're grown and the conditions that they're growing. I guess there's a lot of moving targets out there because of the types of summers and falls that we've been having. Some years are really good and everything is optimized and other years are very challenging and knowing how that's affecting the nutritional landscape for the bees is going to be important indicators of how well will you be able to get them through the winter and into the next spring.

Jeff: Oh, very good. Well, I appreciate you being here and this episode will air probably in September. The folks are just right smack dab in the middle of making sure that they're getting ready for the winter at this point. Get out there and do your mite checks, make sure you got your supplements on and throw in some seasonal pollen too.

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Kim: Good, yes. You got it right, Jeff. Gloria, again thank you very much. This was fun.

Jeff: Thanks, Gloria.

Gloria: Good luck and thank you.

Jeff: Blinding flash of brilliance, a common sense, that's a great way of describing what Gloria and her team have come up with in terms of seasonal pollens.

Kim: I got the press release from the USDA news people and I was two-thirds of the way through it, and it was just incredibly obvious what they'd done. You slap yourself up alongside the head and said, "Why didn't I think of that?" Because it's just, and as she said, lots and lots of animal people have already figured that out, that diets in the spring are different than diets in the fall. She was good at explaining, and I can see how beekeepers can take advantage of that, they can use that information, and in fact, if you're a good entrepreneur, you might be able to develop some products along those lines to help other beekeepers.

Jeff: Yes, it just makes all the sense in the world. Just feeding them what they need to feed at that time of the year.

Kim: By doing that, even with the climate change are bringing about slowly, you can adapt to climate change because if fall comes early with the plants that are in your locale, you'll have pollen from previous seasons that you'll be able to use to accommodate that. If spring comes way early and your bees can't fly, you'll have pollen that you've captured from previous years to accommodate that. I see it as being a big useful tool.

Jeff: I think we're going to have to have Ben and Kimberly Carpenter back from Ross Rounds and Sundance Pollen Traps and talk to us about pollen trapping and educate. I don't pollen trap, you pollen trap, and I wonder how many of our listener's pollen trap, but it's going to become even more important, I think.

Kim: I can see a very useful tool, very useful tool. The indoor wintering thing, I'm glad that John Miller-- John Miller's a scientist in all intents and purposes, although he doesn't have that kind of a degree. He approached his indoor wintering from a scientific perspective and accomplished a lot, and I can see Gloria is doing the same thing. I think when they get their heads together down the road a couple of years, I can see indoor wintering being a very profitable way to spend winter if you're a honey bee and a beekeeper.

Jeff: I'll throw in a plug for our sponsor, Global Patties. Now they advertise the fact that they do custom patties as well. I can see where a large beekeeper who had that collection of seasonal pollen could send that to, say, Global Patties, and have their own set of special seasonal pollen patties for feeding.

Kim: Yes, and then you pull your bees out of the building at the right time, you're feeding them the right pollen, and you move in 10, 12 frames into almonds and make up a bundle.

Jeff: I think we should get out of podcasting and get into that business.

Kim: Yes, I'm right there with you. I think these guys are opening up some doors that-- But it goes back to Varroa. You got to fix Varroa, and you got to do it now in July instead of August. You don't control Varroa, all of this is a moot point.

Jeff: And then if you're trying to control Varroa in July, you're also having to deal with controlling it while honey supers are on, so what a wicked web of challenges that is.

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Jeff: Well, I think with that we are done with this episode. Before we go, I want to encourage our listeners to rate us five stars on Apple Podcast, or wherever you download the stream to show. Your vote helps other beekeepers find us even quicker. 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 reviews along the top of any webpage.

As always, we thank Bee Culture, the magazine for American beekeeping, for their continued support of the Beekeeping Today podcast. We want to thank our regular episode sponsor Global Patties. Check them out at We also want to thank Strong Microbials for their support of this podcast. Check out their probiotic line at

We want to thank Betterbee for joining us. Check out their full line of beekeeping supplies at Finally, we want to thank you, the Beekeeping Today Podcast listener for joining us on this show. Feel free to send us questions, and comments at We'd love to hear from you. Anything else, Kim?

Kim: I think that about wraps it up, I'm ready for some fall pollen.

Jeff: Well, make sure you brush your teeth afterward.

Kim: Okay.

[00:43:46] [END OF AUDIO]


Dr. Gloria DeGrandi-HoffmanProfile Photo

Dr. Gloria DeGrandi-Hoffman

Research Leader

Research Leader at the USDA-ARS Carl Hayden Bee Research Center in Tucson, AZ

Born in Pennsylvania

Received BS in Biology and MS in Entomology from Penn State University

Received Ph.D. from Michigan State University

Trained as a mathematical modeler

Current research interest is in nutrition, Varroa control, cold storage overwintering, and climate change effects on honey bee colonies.