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    The Hive Gallery features photos of beehives, honey bees, honey . . . whatever readers have sent me. Explore

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Keep honey bees dry and draft free

After writing a post about upper entrances in winter, I received a lot of mail from beekeepers who insisted that an upper entrance in winter would place the colony at risk of freezing. My own experience with upper ventilation has been the exact opposite, and my colonies have thrived since I began using upper ventilation combined with a moisture quilt. Nevertheless, I decided I should consult other sources.

In Honey Bee Biology and Beekeeping (2013) Caron and Connor explain:

Colonies can survive very well without elaborate wintering preparations by the beekeeper as long as the bees are protected from winter winds and they are able to vent excess moisture. . . . Beekeepers should provide upward ventilation in every hive during the winter . . . An alternative is to place a wooden shim, carpet tack or stick in one of the corners at the top of the hive. Some beekeepers prefer to drill holes in hive bodies or use spacers or inner covers designed to allow air ventilation.

Beekeeping in Western Canada, published by Alberta Agriculture and Rural Development (1998), puts it this way:

An upper entrance is an important requirement for successful outdoor wintering. The colony cluster gives off water vapour as it respires, which rises to the top of the hive and must be allowed to escape.

A passage in The Hive and the Honey Bee (2015) is equally emphatic:

Thus, beekeepers in cold climates must provide an upper entrance to allow water to evaporate out of the hive by drilling a hole in the box or providing an inner cover with an opening in the rim.

In The Beekeeper’s Handbook (1998), Sammataro and Avitabile insist the winter survival depends on a number of items, including

“An upper entrance for winter/spring cleansing flight” and “Top ventilation to release moist air.”

Bees rarely die of cold

Although it is written in many texts and papers, beekeepers tend to forget that bees are extremely well adapted to staying warm in winter. Contrary to popular thought, they do not keep their entire hive warm in the way a human keeps a house warm, instead they only keep the cluster warm. This is aided to some extent by the structure of the hive, but even open-air colonies can survive a moderately cold winter if they can stay dry and out of the wind.

In chapter 21 of The Hive and the Honey Bee, Currie, Spivak, and Reuter report that a cluster of 16,000 bees can survive -112°F (-80°C) for 12 hours. That is an amazing feat, but to succeed at those temperatures, the cluster must be dry and free of drafts.

This phenomenon is easy to reproduce. Just go outside wearing your regular clothes on a 40°F day (4°C) for 15 minutes. Then try it again wearing the same clothes doused with water. Evaporation is a cooling process. When the water on your skin evaporates, it makes you cold. It will evaporate even faster in the wind, which makes you even colder.

Finding a compromise

Dry bees can withstand extremely cold temperatures, but as they say, a wet bee is a dead bee. So your priority for wintering bees should be to keep them dry and out of the wind. Yes, ventilation provides some amount of air movement through the hive, but there is a give and take between too much and not enough. The trick is to find the sweet spot in the middle.

My enthusiasm for moisture quilts is partly due to this give and take. The moist air moves through the wood chips, condenses on the inside of the lid, and rains down on the chips. The chips collect the moisture and then dry slowly. They dry because the space above the chips is vented to the outside. Once dry, they are ready to collect again. And since the air going through the chips does not have a straight-line path—it must wend its way between chips—there is very little draft inside the hive.

Bumble bees can do it too

The amazing ability of honey bees to keep their nest warm is shared by other bee species as well. In A Sting in the Tale (2013), Dave Goulson describes how he had to destroy a colony of bumble bees because they were brought into his country for research only and could not be released. He decided that freezing them would be the most humane way to kill them, so he put the entire colony in a freezer at -30°C (-22°F). He writes:

The next day I came back to find the colony very much alive and buzzing loudly; the workers had gathered into a tight clump over the brood and were presumably shivering at maximum capacity. The queen was hidden in their centre, and seemed quite unperturbed.

A convenient opening

As I mentioned in my previous post, An upper entrance in winter, before this year I never used an upper entrance, only a number of ventilation ports above the wood chips. This worked fine, but this year I added an Imirie shim with an entrance just below the candy board.

All of my colonies have taken a shine to this opening, peeking out of it on cold days and flying out on warm ones. In fact, the bees in all my hives seem to have abandoned the lower entrances altogether. I wondered about this, but realized that part of the attraction may simply be that it is close. As winter progresses, the cluster moves up. How much easier it is to exit through the top, than to go down three stories and exit through the bottom?

Of course, there may be more to it than that, and it will be interesting to see what they do as the winter warms into spring.

Honey Bee Suite

How I came to have a camo bee suit

Yes, I really do have a camouflage bee suit. It wasn’t an idea that came to me fully formed, but one that evolved piecemeal.

Over the past several years I’ve had frequent encounters with camouflage. The most embarrassing one occurred in 2009 when I was in graduate school at The Evergreen State College. The school is not far from my home, and by using a shortcut through the state forest, I can cover the distance in about 30 minutes, assuming all the trees are still standing.

No way home

On this particular day, we had torrential rains and the local roads were flooded. After class, I got as far as the local post office—a tiny dilapidated trailer that sits alongside a crusty old church—but I couldn’t go any further. It was 10 pm, dark as pitch, and Waddell Creek cascaded over the asphalt. I called home and my husband tried various routes, but he couldn’t find a way either. It was truly a case of “I can’t get there from here.”

Camo day at school
Off to class in my friend’s boyfriend’s rain gear. © Rich Davis.

I called my friend, the assistant postmaster, and she put me up for the night. The problem was that I had a mandatory field trip the next morning and I couldn’t get home before then. I had no clean clothes, no toothbrush, and no way to stay dry in the field. Ever the gentleman, my friend’s other loaned me his brand new, never-been-worn camo rain gear—straight from Cabelas.

Off to class

Bright and early the next morning, off I went to join my classmates and examine the biodiversity of urban forests. It was excruciating. All day long the guys, big handsome rogues half my age, would walk straight into me, nearly knocking me over. “Oh, Rusty! Sorry, I didn’t see you standing there!” At each new stop, the professor would do a head count, then solemnly pronounce, “We seem to be missing someone.” It was a long, long day.

By the end, I never wanted to see camo again. But as things happen, my daughter soon paid a visit and brought me a cache of BDUs she had leftover from her army days. They reminded her too much of Iraq, but they were perfectly good, so she thought I might want them for gardening.

From rain gear to BDUs

It turns out that, with a dirty job on the agenda, they were great. And so many pockets! I love pockets. I began wearing them for more and more things. And then, one day, I started wearing them for tending bees.

I’d always assumed that, being dark-colored, the camo would upset the bees. But they didn’t seem to mind . . . like maybe they didn’t see me either? And my regular bee suits were so gross—with  parallel lines of propolis permanently etched across my hips—that I was happy to have an alternative. Camo barely shows anything.

Then one day I went to the dump, stood in the back of my pickup, and with great ceremony, tossed my old suits into the void below. It was liberating. My suits were so worn and loose they attracted more bees than they repelled. Still, I would need a full suit for those days when I felt like a target.

A camo bee suit from England

My camo bee suit by Natural Apiary. © Rich Davis.

I had decided to try a suit from Natural Apiary. I liked the description, the customer comments, and the fact they had colors, and I especially liked the price. I was planning on the green one, figuring it wouldn’t look quite as bad as white when scored with parallel lines and bee poop. I was just about to hit the “place order” button when a sudden inexplicable urge guided my hand to the camouflage option. I hit that, then ordered.

Afterward, I struggled with this. Was I entirely crazy? Well, yes. Would it be hot in the summer? Of course. Would other beekeepers think I was fried? Yes, but they do anyway. I decided to live with it.

Two days later my suit arrived. I loved it! I wanted to wear it to dinner. It was described as having eight pockets, but it actually has ten if you count the ones on the sleeves, and it fits better than any suit I’ve had before. It has all the creature features of a good suit, and just think: my “mortified of bees” neighbors won’t even see me out there!

The trouble with pockets

The second day I wore it, though, I had a problem. Remember all those pockets? Big, deep pockets? Well, I dropped my keys in one and forgot about them. At the end of the day, I hung my prized suit in the garden shed, locked up for the evening, and forgot about the keys until the next day when it was time to let the chickens out of their coop.

I live in the woods along with all kinds of things that are not conducive to hen health, things like foxes, owls, weasels, and ermines. So we lock down the birds at night. But as soon as I went to release them the next morning, I remembered my keys in the pocket of my new bee suit, which was safely looked in the shed where I couldn’t get them. The chickens squawked a fright and I couldn’t bear to leave them incarcerated all day.

To the rescue

The chicken coop has two doors. One for humans and one on the opposite end appropriately sized for chickens. Once the chickens exit, they go down a ramp and through a wire tunnel that leads across a corner of the vegetable garden and through a second appropriately-sized entrance into their own yard.

To open their door from the outside, I would have to go through this second “appropriately-sized” entrance. It went like this:

  1. Wear BDUs
  2. Ignore rain and hail
  3. Lay face down in 16 years worth of chicken s–t
  4. Pull self through 12” x 16” wire opening
  5. While laying on stomach, reach through tunnel and pry wooden door with crow bar (which I actually remembered to bring)
  6. Say “good morning” to chickens
  7. Pull self back through the 16 years worth
  8. Injure both hands on the way out
  9. Write about experience
  10. Clean blood from keyboard

That was yesterday. Today my right hand is bruised and swollen but I can still type. I have my keys. The chickens are happy. I haven’t figured out what to do with all those extra bees, but I’m still in love with my camo bee suit.

Honey Bee Suite

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Notice Board . . .

In case you missed it: A Song of the Bees

Bee Lover’s Bookshelf

Honeybee Democracy by Thomas D. Seeley. 2010. The book explains in great detail how honey bee swarms decide on a new home and how they agree on when to move. Seeley provides his raw data in charts and graphs, as well as his conclusions and insights. The book is not easy reading (you have to pay attention), but it’s packed with interesting tidbits about swarms. Good photos, too. Honeybee Democracy

Bees: A Natural History by Christopher O’Toole. 2013. This is a coffee table book about bees. (Do people still have coffee tables?) Anyway, large format with large awesome photos. It’s a good place to start if you know nothing about native species because it’s not too technical yet gives a broad overview. Fairly easy to read, a nice introduction to bees. Bees: A Natural History

The Bee: A Natural History by Noah Wilson-Rich. 2014. This book has a little of everything–a good overview of bee biology, anatomy, behavior, and evolution, as well as interesting sections on the the environmental challenges faced by bees and the interaction between bees and humans. There is even a section on beekeeping. The book covers a lot of ground without too much depth in any one area, but it is well-written and well-illustrated. The Bee: A Natural History

Bumble Bees of North America by Paul Williams, Robbin Thorp, Leif Richardson, and Sheila Colla. 2014. This is an in-depth guide to bumble bee identification. Although it will tell you everything you ever need to know about North American bumble bees, I find it difficult to use. Most of the problem lies within the genus Bombus; because bumble bees are so variable, it is extremely difficult to tell them apart. The book includes keys, photos, coloration diagrams, and excellent distribution maps–lots of information but not for the feint of heart. Bumble Bees of North America: An Identification Guide (Princeton Field Guides)

A Sting in the Tale: My Adventures with Bumblebees by Dave Goulson. 2014. Some books I don’t want to end, and this was one. It reads like a cross between a novel and an adventure story as it follows the author’s fascination with bumble bees from childhood to the founding of the Bumblebee Conservation Trust. Along the way you will learn more about bumbles than you ever thought possible. A Sting in the Tale: My Adventures with Bumblebees

A Buzz in the Meadow: The Natural History of a French Farm by Dave Goulson. 2014. This is a story about how the author purchased a 33-acre farm in rural France and turned it into bumble bee habitat. Insects, flowers, wildlife, nature, and the curious mind of an entomologist makes for entertaining and readable science. I never tire of reading Goulson’s work. A Buzz in the Meadow: The Natural History of a French Farm

Field Guide to the Common Bees of California Including Bees of the Western United States by Gretchen LeBuhn. 2013. As soon as this book arrived in my mailbox, I read straight through it three times. The author selected the most common genera of bees in her location and for each genus she provides­­ detailed illustrations by Noel Pugh, a genus summary, description, similar insects, food resources, nest particulars, and flight season. She even includes a pronunciation guide. Field Guide to the Common Bees of California: Including Bees of the Western United States (California Natural History Guides)

California Bees and Blooms: A Guide for Gardeners and Naturalists by Gordon W. Frankie et al. 2014. You don’t have to be from California to appreciate this book. The book details the basic families of bees and the plants they like using colorful photos of both. It also explains the complex relationship between bees and flowers and explores ways to build better native bee habitat. California Bees and Blooms: A Guide for Gardeners and Naturalists

The Forgotten Pollinators by Stephen L. Buchmann and Gary Paul Nabhan. 1996. This is a book about plants, pollinators, and their amazing interdependent relationship. Well written in a story-like format, the book follows the authors’ research into the “pollination crisis” and disruption of some of the world’s most fragile ecosystems, including the rain forests. The Forgotten Pollinators

Keeping the Bees: Why All Bees Are at Risk and What We Can Do to Save Them by Laurence Packer. 2010. This is one of my favorites even though it has only four pages of photos. The book follows the adventures of Packer and his associates as they study bees here and there throughout the world. The book is packed with information about bees and bee decline. Keeping the Bees: Why All Bees Are at Risk and What We Can Do to Save Them

The Buzz about Bees: The Biology of a Superorganism by Jürgen Tautz. This is my number one choice for basic honey bee biology. Amazing photos and excellent descriptions of how the bee and the colony actually work. I refer to this book constantly. The Buzz about Bees: Biology of a Superorganism

Pollinators of Native Plants: Attract, Observe and Identify Pollinators and Beneficial insects with Native Plants by Heather Holm. 2014. This book looks at native plants and the pollinators and beneficial insects that are attracted to them. The author divides the native plants into different habitat types, shows what they need to thrive, and describes what pollinators and beneficials you will most likely see. Pollinators of Native Plants: Attract, Observe and Identify Pollinators and Beneficial Insects with Native Plants

Bee by Rose-Lynn Fisher. 2010. This is picture book for honey bee lovers. The photographs, taken with the aid of an electron microscope, reveal the honey bee and all her parts in stunning detail. Whether you are a beekeeper, gardener, photographer or just curious, this book is a joy. There is nothing like seeing the parts up close to understand how they all work together to pollinate our world. Bee

Bees: An Up-Close Look at Pollinators Around the World by Sam Droege and Laurence Packer. 2015. This is essentially a picture book, but the photos are far from ordinary. The book contains extreme close-ups of some of the worlds most fascinating bees with write-ups about each one. Bees: An Up-Close Look at Pollinators Around the World

The Bees In Your Backyard: A Guide to North America’s Bees by Joseph S. Wilson and Olivia Messinger Carril. 2016. My new favorite. The book is chock-full of identification tips, including photos of wing veins, detailed depictions of facial patterns, tongue diagrams, and photos of similar genera. Each genus has a pronunciation guide, a size-range diagram, a distribution map that shows not only where the bee occurs but also the likelihood of occurrence in that area. Best, the book contains hundreds of little highlighted text boxes that reveal bee trivia, and the whole thing is well-written and easy to understand. The Bees in Your Backyard: A Guide to North America’s Bees

Honey Bee Parasites, Pests, Predators, and Diseases by Penn State College of Agricultural Services. 1999. This is a handy little spiral-bound book with good photos of honey bee ailments. I use it frequently for the pictures, but I find it a little out of date with no mention of Nosema ceranae, colony collapse, or many of the viruses. Also it leans heavily toward chemical solutions rather than management and prevention. Good news: there is a new edition (2005). Honey Bee Parasites, Pests and Predators & Diseases

The Queen Must Die: And Other Affairs of Bees and Men by William Longgood. 1985. This is the only bee book I’ve asked my husband (not a beekeeper) to read. The author interweaves plenty of good information about bees and beekeeping with thoughts and reflections on nature and mankind. I highly recommend this one. The Queen Must Die: And Other Affairs of Bees and Men

Beeing: Life, Motherhood, and 180,000 Honeybees by Rosanne Daryl Thomas. 2002. This is a nature memoir about a recently divorced woman who rebuilds her life around bees. The writing is lyrical, the story is novel-like, and her descriptions of beekeeping are entertaining. Beeing: Life, Motherhood, and 180,000 Honeybees

The ABC & XYZ of Bee Culture, 41st edition by A.I. Root Company. 2007. The book has a little of everything, but because it tries to cover every conceivable topic, it doesn’t go into depth about anything. It does have some good photos and a few sections are fairly complete. Oddly, about half of the book is biographical information about dead beekeepers. Works well as a booster seat. The ABC & XYZ of Bee Culture: An Encyclopedia Pertaining to the Scientific and Practical Culture of Honey Bees

The Backyard Beekeeper: An Absolute Beginner’s Guide to Keeping Bees in Your Yard and Garden by Kim Flottum. 2005. This very popular book is not my favorite. It’s hard to say why, but I think it is confusing to beginners, perhaps because of the way the material is presented or the order. Not sure. It didn’t give me a warm-puppy feeling when I read it. I think it spends too much time pushing eight-frame equipment, and the candle-making and recipe sections should be in a separate book. Good glossary and photos. Backyard Beekeeper

The Beekeepers’s Handbook, Fourth Edition by Diana Sammataro and Alphonse Avitabile. 2011. This is my first choice for an overall beginner how-to book. The sequence is logical, the explanations are clear and concise, and it gives you enough to get going without overwhelming your brain. Many clear diagrams, bulleted lists, and appendices. If you can buy only one beekeeper book, buy this one. The downside to the third edition: the shape of the book (short and wide) is really annoying and it doesn’t fit on many bookshelves. Why did they do that? The Beekeeper’s Handbook

The Quest for the Perfect Hive: A History of Innovation in Bee Culture by Gene Kritsky. 2010. The book is a history of hive design from ancient times to the present, including drawings, photos and descriptions of what worked, what didn’t, and why some hives were more popular than others regardless of how they worked. This book is a pleasure to read and gives good insights into how beekeeping today is strongly rooted in the past. The Quest for the Perfect Hive: A History of Innovation in Bee Culture


How to Apply an Oxalic Acid Dribble to Control Varroa Mites

What is oxalic acid? Basically it is an organic (carbon-containing) compound that is found in nature. A number of foods we eat are rich with oxalic acid, including spinach, swiss chard, rhubarb, beet greens, kale, sorrel, and chocolate. In fact, there is much speculation that the “spinach effect”—that weird mouth feeling some people get after eating spinach—is actually caused by oxalic acid. And we’ve all heard that rhubarb leaves are poison. The reason? Oxalic acid.

Since oxalic acid is found in nature, and because it is a normal component of honey, oxalic acid is considered a “natural” treatment. In fact, even Certified Naturally Grown beekeeping allows the use of oxalic acid for the treatment of Varroa. Oxalic acid is commonly sold as “wood bleach” and can be found in hardware and paint stores. The type I use can be found here: Savogran 10501 Wood Bleach.

However, oxalic acid in the form that works to kill mites is a potent acid, so care must be taken to avoid causing harm to your bees and yourself if you decide to use it. You should begin by reading the new draft label so you know how to handle the acid and how to protect yourself from splashes and spills.


Oxalic acid can be applied as a dribble, a spray, or a vapor. Since I am a hobby beekeeper with a small number of hives, I prefer the dribble. Personally, I don’t want to buy, clean, or store vaporizers or sprayers, so I’m happy with a box of disposable syringes that I bought online for the purpose. The KISS method works for me, especially in this case.

If you use the oxalic acid dribble method, you will need a canister of wood bleach, a syringe that holds at least 50 ml, a small scale that can measure in grams (tenths or hundredths of grams is best), a standard measuring cup, sugar, and a non-reactive container for mixing. Your wood bleach should be between 95 and 100 percent pure. If you don’t know, you can search the web for the MSDS (Material Safety Data Sheet) for your particular brand and it will tell you.

The other item you will need is soft water. Soft water is an excellent solvent, but when the water is filled with hardness minerals (chiefly calcium and magnesium) it tends to form deposits or precipitates instead of dissolving things. If you see a white substance in the bottom of your container after you mix in the oxalic acid, you should toss that batch and try a different source of water. If you don’t have a water softener, you can use distilled, deionized, reverse osmosis, or even rain water.

According to the new EPA label, you need to mix 35 grams of oxalic acid dihydrate crystals into one liter of 1:1 syrup. (This is the same as Randy Oliver’s weak solution, and the one I’ve been using.) You can make a liter of syrup by using 600 ml of water and 600 grams of table sugar.

Time of application

  1. Because oxalic acid will not kill Varroa in capped brood, I like to apply oxalic acid at times when little or no brood is present but before it is crazy cold outside. For me, this is late fall.
  2. Treating once per year at the right time may be enough because this system knocks Varroa down to almost nothing.

Prepare solution

  1. Measure 600 ml of hot water into a non-reactive container.
  2. Add 35 grams of oxalic dihydrate crystals (wood bleach) into the hot water. Stir but do not shake.
  3. When the crystals are dissolved, add the 600 grams of sugar. Stir until dissolved.

Apply the solution

  1. Smoke your bees down between the frames.
  2. Dip the end of your syringe into the medicated syrup and pull back the plunger, filling the syringe to the 50 ml mark.
  3. Starting at one end of the frames, dribble 5 ml of the solution along a seam that contains bees. (I like to start at the far end and dribble toward me.)
  4. Once you have dribbled 5 ml, you must go on to a new seam. (A seam is the space between two frames or the space between a frame and a sidewall.)
  5. After each seam of bees gets 5 ml of solution, you are done.
  6. In any case, you cannot go over 50 ml per colony. If the hive has more than 10 seams, dribble where the most bees are. Alternately, you can give less than 5 ml per seam and do more than 10 seams, but you cannot go over 5 ml in any one seam or 50 ml total per colony.
  7. Remember to apply the mixture directly onto the bees. Mixture that lands on the woodenware will be ignored by the bees and not moved throughout the colony.

Dribble practice

I strongly suggest that you practice dribbling with plain syrup in advance. The first time I did a test, I squirt syrup half way across the room. Seriously, it takes a little skill to get the hang of moving the syringe along the seam while gently pressing the plunger. Also, practice reading the graduations. My syringes are marked 10, 20, 30 and so on with five divisions between each one, so five ml is 2.5 divisions. I use this type of syringe: Syringe 60cc Luer Lock Tip Sterile (Pack of 10).

Be sure to use 1:1 syrup for your trial runs because plain water behaves differently. I also recommend putting 5 ml (1 teaspoon) of syrup in a dish so you can see what it looks like.

Once you get a feel for it, you will find that moving quickly along the seam is easier than moving slowly. Also, watching the drip end seems to be easier than watching the graduations once you learn how fast it comes out. Five ml doesn’t seem like much when it’s whiskey, but this stuff is different.

So there you have my method. If you want to use a vaporizer or sprayer, I strongly suggest you read the label and Randy Oliver’s site for the best information.

A Demonstration Video

Here is a great little video that shows how to apply an oxalic acid dribble. It features Bee Craft Deputy Editor, Margaret Cowley (UK). She has the coolest little plastic squirt bottle that dispenses exactly 5 ml of the solution at a time. She just squeezes the bottle until the upper chamber is full, then she applies the measured amount into a seam of bees. After each seam, she refills the chamber and repeats.

The treatment is being applied on a December day with temperatures around 42-43 degrees F in a hive with one brood chamber and a super for winter. She treats the entire hive in a matter of moments—as fast as she can re-load the dispenser. Also of interest in this four-minute video is the cat and the woodpecker netting. (I love cats and never heard of woodpecker netting!)

Then too, Margaret cracks me up. As she trickles the solution, a little bee pops up between the frames and Margaret interrupts her narration to say, “hello.” So cute.

Be sure to enjoy.


"CSIRO ScienceImage 7306 A European honey bee prepupa with varroa mites" by CSIRO. Licensed under CC BY 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:CSIRO_ScienceImage_7306_A_European_honey_bee_prepupa_with_varroa_mites.jpg#/media/File:CSIRO_ScienceImage_7306_A_European_honey_bee_prepupa_with_varroa_mites.jpg
“CSIRO ScienceImage 7306 A European honey bee prepupa with varroa mites” by CSIRO. Licensed under CC BY 3.0 via Wikimedia Commons – http://commons.wikimedia.org/wiki/File:CSIRO_ScienceImage_7306_A_European_honey_bee_prepupa_with_varroa_mites.jpg

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