Sunday, June 17, 2012

Double Duty Pollinators and Plants - Brillat-Savarin and Milkweed

live bees stole the show
Yesterday I helped out at the Pollinator Festival organized by Sabrina Malach at Evergreen Brickworks.

 I was in my ceremonial pollinator regalia, but the real stars of the show were the honeybees in a glass demonstration hive at the table next to us. Live bees trump top hats.

Bob Wildfong
Bob Wildfong of Seeds of Diversity was staffing the booth and we chatted about sundry matters relating to pollinators and seeds. Seeds of Diversity and like-minded groups work to keep old-fashioned non-patented plant varieties available to the public. Of course pollinators are an essential part of helping create many of these seeds each year. Which brings me to my main topic, food.

We visited The Encampment at Fort York a few days ago (part of the Luminato Festival). Just as the sun set a cloud of June beetles began to fly. This attracted a flock of gulls who swooped amongst the tents gobbling up beetles on the wing. It was a June food moment. I hope someone with a video camera caught that magic moment with white gulls swooping down the aisles of white tents with surprised and in some cases panicked people (a Hitchcock moment, perhaps?).

Jean Anthelme Brillat-Savarin
At any rate when I exited the Fort through the gift shop I was dreaming of yummy crunchy bugs. That's why I succumbed and bought two food books: Brillat-Savarin's The Physiology of Taste and Native Harvest: American Indian Wild Foods and Recipes by E. Barrie Kavasch. Today I alternated gardening and reading and preparing for dinner.

On the way to the cottage yesterday we stopped at a farmhouse and bought a pint of freshly picked, unsprayed strawberries. It has been a bit dry this spring, so the berries were not huge and plump the way commercial irrigated varieties are. However what they lost in volume they more than made up for in sweet, concentrated taste. A few weeks ago I watched native bees visiting the wild strawberry flowers in our cottage lawn, and now they are ripe too - tomorrow morning I will pick a few of the tiny but intensely flavorful berries for breakfast.

Sheila Colla, bumblebee expert

At the Pollinator Festival I ran into bumblebee expert Sheila Colla. She explained to some visitors to the Pollinator booth that we do indeed have two species of bumblebees that have become somewhat more common (perhaps aided by the decline of honeybees), but that we have many fewer of other bumblebee species. This set me to thinking of that bumblebee-pollinated fruit, the blueberry. It's a little early for fresh ones so I bought a bag of frozen wild berries from a store. They are much smaller than the huge but relatively flavorless commercial varieties. Tonight we will have strawberries, blueberries, and wildflower honey on vanilla ice cream as desert. Heaven in a mouthful!

Jean Anthelme Brillat-Savarin extols sugar in his book but if he has anything to say about honey I must have missed it. Brillat-Savarin preferred meats, vegetables, and fats to carbohydrates; he warned that excessive consumption of sugars and carb-rich food led to obesity. So, it is to Native Harvests that I must turn for wonderful recipes using honey.

E. Barrie Kavasch
Barrie Kavasch notes that many tribes refined maple, birch, and other saps to get sweets long before Europeans brought honeybees to the Americas in 1622. Yet, once loose in the great forests with their abundance of tree hollows for nesting in, honeybees probably outran European settlers. They were present in the wild in abundance from about 1650 onwards, giving native tribes lots of time to incorporate honey into their cooking.

I have to admit that I got overexcited reading recipes such as "Hickory-Nut Corn Pudding" with its honey, nut butter, and goldenrod flowers, or the "Cranberry-Walnut Cakes" with honey, walnuts, cranberries, and cattail flour (which is actually pollen). Keeping in mind Brillat-Savarin's warnings about excessive sweets, I looked for other dishes for the main course.

It's early in the summer here at the cottage so we don't have spices for making barbecue sauce the way I like it (tragically, the Tabasco sauce got left at home). Nonetheless when I found pork side ribs on sale I felt I must do something with them. Weeding in the garden, I was thinning hundreds of Russian Red kale seedlings and decided to cook them with the pork. Kale is biennial; I always leave a few plants to overwinter and bloom the next June, and today I watched bees visiting their yellow flowers. Seeds from these plants will ripen and drop in the garden and give me seedling to transplant next spring. I've been doing this for 15 years and the garden is always full of kale seedlings.

Mature kale leaves become tough and bitter and need long slow cooking or frost to make them palatable, but seedlings are much tenderer. I harvested a large bunch of them, chopped them finely, mixed them with sage leaves, thyme flowers, and fresh fennel sprout and laid them in the bottom of a ceramic dish. Over them I laid the ribs, then another layer of kale. I poured balsamic vinegar over the mix and then dribbled 2 teaspoons of wildflower honey on top. Covered with foil, the ribs and kale cooked for 5 hours in the oven at about 225F. When served, the kale was delicious!

milkweed - use green buds. Wikimedia.

We have an outstanding display of common milkweed plants (Asclepias syriaca) in the field next to the garden. Near the summer solstice these are not quite in bloom, so at the perfect stage for picking the green flower bud clusters and the small tender leaves that shelter them. The tip of each shoot had 3 bud clusters; I picked only one, leaving two to form pods, some of which I will harvest and pickle in a few weeks. I rinsed the buds and boiled them for 8 minutes, then drained them. They were just as delicious as Kavasch had promised; I succumbed and had mine with a bit of mayonnaise.

I have been encouraging milkweeds for years as a food source for monarch caterpillars, but never imagined I could eat them too. The plants are full of bitter compounds, but boiling the young shoots, leaves, buds, or pods breaks down the bitterness.

Milkweed, kale,  honey, strawberries and blueberries; bees and monarchs; a feast to celebrate Pollinator Week!

Thursday, June 14, 2012

Neonicotinoid pesticides under review in Canada

Health Canada just announced they are re-evaluating the safety of the neonicotinoid pesticides Clothianidin, Thiamethoxam, and Imidacloprid.

The government of France recently proposed to ban thiamethoxam (Cruiser), which is used to treat canola seed before planting. France and Germany both banned some uses of imidacloprid in 2003 and 2008 respectively (see this balanced Wikipedia article for details). U.S. beekeepers and British environmental groups have called for their governments to ban these compounds.

A large number of recent scientific studies that show these pesticides can harm pollinators, including honeybees and bumblebees. These papers have come from a number of different researchers and many of them have been quite rigorous and published in high-profile journals where every article gets very careful peer-review. They include:
  • A study to be published this month from Harvard School of Public Health scientist Chensheng Lu fed honeybee colonies with high fructose corn syrup containing levels of imidacloprid found in the environment (corn seed is treated, and the pesticide travels throughout the plant). Colonies given the pesticide-laced syrup died suddenly, months later, in a manner reminiscent of Colony Collapse Disorder (CCD).
  • Christian Krupke's group at Purdue University showed that treated seed releases pesticide into the environment in several different ways, that pesticide gets into bees, and that it harms them. I covered this report in a January blog entry.
  • Italian researchers showed small droplets of sap released by corn seedlings are highly toxic to bees when the seed was treated.
  • British researchers published in the top journal Science showing that bumblebee colonies exposed to realistic levels of these pesticides produced 85% fewer queens to carry on the species next year.
These are just a few of the many careful articles published in the last few years on this subject. The evidence that neonicotinoid pesticide as used in current agricultural practices can and does harm bees is overwhelming.

Of course Health Canada will take some time to come to a decision - this is a government bureaucracy after all. During that time the manufacturers of neonicotinoid pesticides will lobby the government vigorously. It's a good time to get a cool drink, a pen or laptop, and write a letter to your MP expressing your views on this issue.

Friday, April 6, 2012

What does NAFTA have to do with pollinators?

Melanie McCavour & Clement Kent - in the greenhouse
In February we went to Montréal to talk about pollinator gardens at Concordia University. It was delightful to talk with students and staff in the greenhouses on top of the Hall building in downtown Montréal. Volunteers create a variety of urban farming projects as a project of Sustainable Concordia. It was amazing to look out and see snow on the Mountain while being too hot to keep the tuxedo coat on. 

The audience looked very comfortable sitting in the afternoon sun among the plants! 

herbal greenhouse tea with science honey
After the talk we had herbal tea from plants grown in the greenhouse and a sampling of wildflower honey from our York University bees.




Melanie McCavour, Lecturer at Loyola International College (Biodiversity) and GPE (Plant Ecology) invited us to Concordia. I first met Melanie at the 2011 North American Pollinator Protection Campaign (NAPPC) conference in Washington DC, where she spoke about NAPPC’s efforts to have pollinator biodiversity protected under NAFTA. Because I had missed part of Melanie’s Washington talk, we sat down with her in the greenhouse to find out more about her work in Washington, Mexico, and Montréal to protect pollinators.

Melanie studies forest ecology. In 2009 she was an intern in R&D at the National Capitol office of the USDA Forest Service where she had the opportunity to work on projects on global change, bioenergy and invasive species certification.  In the same year, Peter Kevan, head of the CANPOLIN pollination research group asked her to be a reporter at the 2009 Round-table on NAFTA, Food Security and Pollination at the Canadian Embassy in Washington D.C., which introduced her to efforts to use existing tri-lateral agreements under NAFTA between Canada, the U.S., and Mexico to improve pollinator protection, both native and non native bees (Apis mellifera) and other pollinators, such as bats and butterflies. NAPPC and others have recently released a policy statement on importation of non-native bees.  Since then she has been involved in efforts by NAPPC to work with the 3-nation NAFTA Commission for Environmental Cooperation (CEC) to deal with pollinator issues. A few years ago, the CEC produced a report on the monarch butterfly, a pollinator who  migrates between our 3 nations, and is an obvious organization to further awareness of the value of pollinators and the necessity of trilateral protection in North America.

The CEC was created in 1994 to address questions about the environmental impacts of the NAFTA treaty. Each nation is represented on the CEC differently: Canada is represented by the Minister of the Environment or his designee, while the USA is represented by the EPA. Melanie notes that the EPA has a far more regulatory role than the Canadian or Mexican Minister of Environment and in the U.S., some political groups view the EPA with great suspicion, so it can be very challenging to add new language to US laws or regulations to improve pollinator protection. Hence she and her collaborators on the NAPPC NAFTA committee have been searching for ways to clarify ( through external statements perhaps) existing treaty or regulatory language to make clear the importance of pollinators and their protection. For example, given that NAFTA is focused on trade, and agriculture is the single biggest beneficiary (in trade terms) of pollinator services, how can national or tri-national agreements on agriculture be clarified to protect the vital role of pollinators?


At the most recent CEC Council meeting, on June 22nd, 2011, Melanie wrote and presented orally a statement on behalf of CANPOLIN and NAPPC to the CEC Ministers. Ministers Juan Rafael Elvira Quesada, Lisa P. Jackson, and Peter Kent expressed enthusiasm for the statement and encouraged her to submit a proposal to the new NAPECA –a CEC funded community action grant. You can see Melanie’s presentation to the CEC and some of the news coverage it generated. Listen for her comment on essential products in which pollinators are involved, such as tequila and coffee. One of the themes of the CEC proposal I found interesting is to include pollinators and pollination within the “Payment for Ecosystem Services” (PES) document of the CEC.

Although Melanie did subsequently apply for a NAPECA grant for a review on pollinators and their value in N.A., it did not receive funding through NAPECA for the 2011-2012 year; it is hoped that this study might be funded by the Mexican Ministry or NAPECA next year.

Given some of these political challenges, one way forward has been for Canada and Mexico to cooperate to define and agree on positions and then bring them to CEC/NAFTA. This was the motivation for a Canada-Mexico meeting last year at the Cholula Ethnobotanical Gardens in Cholula Mexico.  I was delighted to receive as a thank you gift a bottle of honey for my laboratory’s collection from a local apicultural farm in Cholula and some locally produced tomato wine from Quebec.

Montréal en Lumières
After meeting Melanie and her colleagues at Concordia, we were able to enjoy some of the happenings going on in Montréal, including the Montréal en Lumières festival and ice skating on the Mountain. We thank our friends at Concordia for inviting us to visit la belle ville!




Saturday, January 21, 2012

Scent or touch? The art of Penelope Stewart at the Edward Day Gallery

A George Cruikshank's illustration for  Tristram Shandy
One of my favorite books is Tristram Shandy, and in honour of this the current posting will  meander just a bit down Queen Street before getting to the pollinator-related material. So, imagine yourself a flighty butterfly rather than an industrious, bee-line-following worker bee, and fly with me to sip at a few forms of art...

John Greyson
My partner Leena and I just returned from a pleasant walk in the afternoon sun on Queen Street. We went to Woolfit's to look at art supplies, then dropped in to T.A.N. Coffee where we ran into filmmaker John Greyson, who teaches in York University's Film department. John was enjoying the band playing in the cafe while interviewing crew for his next production.

We also popped into the Ontario Crafts Council gallery  to look at the Losing Parkdale show. The lovely piece by Dennis Lin using wood veneers evoked the saying that "civilization is a very thin veneer over barbarism" (from The Return of Tarzan (1912) by Edgar Rice Burroughs). The swoops and curves of Lin's veneers reminded me how precariously our civilized veneer clings to the underlying id and ego. Indeed, Losing Parkdale is about how "civilization", in the form of condo development, is displacing a large community of artists (less civilized?) from the community in which they have lived and worked for years. To quote from the statement for the show:

"Losing Parkdale focuses on the neighborhood of Parkdale as a community of woodworking talent. The exhibition showcases a few of many hugely talented artists and craftspeople that have made their living in this part of Toronto.

Sadly, studios in Parkdale are currently being displaced for condo development, thereby reducing the pool of usable working space in the neighborhood. As this is being written John Jackson's building has just been emptied, sending 100 artists out to try and find new work spaces. Scott and Joe's building has been sold and will be empty in the near future, and will again affect another 40 businesses."

But I don't want to be too negative about veneers. No lesser a thinker than Vaclav Havel has given us another take on civilization and veneers:

the late, great, Vaclav Havel
"Many of the great problems we face today, as far as I understand them, have their origin in the fact that this global civilization, though in evidence everywhere, is no more than a thin veneer over the sum total of human awareness, if I may put it that way. This civilization is immensely fresh, young, new, and fragile, and the human spirit has accepted it with dizzying alacrity, without itself changing in any essential way. Humanity has gradually, and in very diverse ways, shaped our habits of mind, our relationship to the world, our models of behavior and the values we accept and recognize. In essence, this new, single epidermis of world civilization merely covers or conceals the immense variety of cultures, of peoples, of religious worlds, of historical traditions and historically formed attitudes, all of which in a sense lie "beneath" it. At the same time, even as the veneer of world civilization expands, this "underside" of humanity, this hidden dimension of it, demands more and more clearly to be heard and to be granted a right to life."

From barbarism and Burroughs to multiculturalism and Havel! I think Tristram Shandy would have approved of such elegant swerves, and swerve we did as we turned left into the courtyard of the Museum of Contemporary Canadian Art, and again to the left (take that, Stephen Harper!) into the Edward Day Gallery.

We were there for the opening of Penelope Stewart's "Haptic Exchanges". Stewart has been using beeswax to make cast tiles, which she assembles in to large mosaics. The smell was wonderful, the colors ranged from palest amber through brick to gray-brown, and the surface patterns of her casts lead the eye to wander in a Shandy-an fashion.

Aganetha Dyck, Queen, 2007
"Haptic" refers to touch, and these are art pieces meant to be touched, a bit of a problem for all of us well-trained museum goers who look but never touch...

Stewart told us that in the course of making some of these very large installations (those at the Albright Knox Gallery and the Oakville Gallery filled rooms) her beeswax supplier in the Ottawa area ran out of wax. Fortunately, she had made the acquaintance of Winipeg bee artist Aganetha Dyck and learned about a Manitoba beekeeping cooperative that was able to supply the precious wax.

Barbara Evans
We had the pleasure to run into another  York U Film prof, Barbara Evans, who was gathering footage at the opening for her planned film on pollinators and artists. She has some marvelous ideas but is looking for funding, so if you are a pollinator-loving, filmophile plutocrat, contact her at once!

I urge you to drop by the Edward Day gallery and take in this show - but if you have a cold, come back another day, because you must be able to smell the work, as well as touch and see it! And read the excellent review by Murray Whyte in the Toronto Star for more information...

Why is the smell of beeswax so evocative? someone asked Mr. Shandy. As one beekeepers' website said, "because it smells like honey, duh!". And it does a bit - but only if you get unfiltered honey which still has tiny bits of wax, not the industrial ultrafiltered, sterilized grocery store stuff. It has many other scents in it, like pine trees from the propolis the bees use to glue things down. That's why beeswax absolute has been used in perfumes for centuries, and is still a very important base in fragrances with all-natural ingredients.

shaving a frame to remove the wax
Or perhaps beeswax reminds you of the wood furniture at your aunt's or grandparent's house. Beeswax wood polish has a very long history of use, but if you want to make some of your own as this recipe describes, please stop after the rendering step rather than going on and refining all the scent out of it!

pysanky
Laurence Stern, by Joshua Reynolds
Of course beeswax is a good base for ointments and balms - one of the dozens of uses documented at this website. What else do you know that's used in Archery Wax, Bagpipes, Blacksmithing, Bullet Lube, Cracked Hooves, Didgeridoos, Dreadlocks, Ear Candling, Encaustic Painting, the Lost Wax process of sculpture casting (which was used for Penelope Stewart's black glass cast of a traditional skep or woven beehive), Moustache Wax, Oil Spill Control, Pool Tables, Pysanky, Whipmaking, and Wire Pulling? Laurence Sterne could have written several more volumes of Tristram's adventures from this list!

Roxanne Quimby, dog friend, Burt Shavitz
Speaking of ointments, as we were just a list or so ago, who is the richest beeswax ointment provider in the world? It's probably Roxanne Quimby of "Burt's Bees". Roxanne and Burt founded the company in backwoods Maine when Burt, the beekeeper, was living in an old turkey coop. Later, she bought him out for $130,000. She's now worth $300,000,000 and Burt's Bees is now a division of Clorox, having been solf for just under a billion dollars. Burt still lives in the turkey coop, but after complaining to Roxanne he got four million bucks and Burt's Bees got the right to continue using his rustic image on the products.

This real-life rags-to-riches story has got many twists and turns and several sides, just like a Shandy adventure, as you can read here and here and here. The last link tells how Quimby is using some of her money to buy up land in Maine, with the goal of creating a national park. It's amazing how, if you're a bee multi-millionaire, you become a magnet for opposing views. Some in the environmental movement call Burt's Bees a "sell-out", the local hunters in Maine oppose Quimby's land purchases because she's against hunting, but I know that Burt's Bees is also a significant corporate contributor to both research and public action on preserving pollinators.

As a pollinator gardener, I have an unopened packet of Burt's Bees Gardener's Hand Balm, or some such thing, that was given to me. I just went to open it to see how it smelled, but it appears to have gone into hiding, or perhaps it's with Amelie's father's gnome on his journeys around the world. Or perhaps it's lubricating the chapped hands of members of the Garden Gnomes Liberation Front as they pursue their duties.

But of course I have kept the best use of beeswax for last: candles. As the excellent Wikipedia article tells us, the first known candles were made in China of whale fat about 2,200 years ago, but by 1,700 years ago the Chinese were known to have beeswax candles. In the Middle ages most candles were made from rendered animal fat and stank, both when being made and when burning. Beeswax candles were reserved for the rich and for churches, where their perfume added to the scents of incense.

Presentation of Christ at the Temple, Hans Holbein the Elder, 1500
Beeswax candles were central to the rites of Candlemas, February 2. This celebrates the presentation of infant Jesus at the Temple, that is his pidyon haben, (Hebrew: פדיון הבן‎).  "Traditionally the Western term "Candlemas" (or Candle Mass) referred to the practice whereby a priest on 2 February blessed beeswax candles for use throughout the year, some of which were distributed to the faithful for use in the home." (quote from Wikipedia).

So, with the scent of blessed beeswax candles, I reluctantly leave our Shandyesque trip down Queen Street.

Wednesday, January 18, 2012

The amazing Louie Schwarzberg - fantastic pollinator clips

Louie Schwarzberg
I owe big thanks to artist Valerie Knapp for bringing the TED talk by Louie Schwarzberg to my attention. Mr. Schwarzberg does stunning time-lapse and high-speed filming, and in his upcoming film "Wings of Life" he turns his eye and his camera to pollinators and flowers. The film already premiered in France as "Pollen" but I don't think it has had a North American premiere yet.

The only way to do justice to his artform is to watch it. Click on the TED talk link above. It has a minute or two of him talking about the work, then 5 minutes of the lushest, most amazing imagery of pollinators you'll ever see. Personal favorites: the bee showering herself in pollen, the hummingbird doing barrel-rolls in the air as it chases a bee away, and the bat hovering over a cactus flower.


Schwarzberg filming monarchs
I visited Schwarzberg's site www.movingart.tv and was interested by some of his new ideas coming up and other things he has done. In particular, I paid US$2.99 to buy a copy of his film of flowers in motion, "Naked Beauty".

p.s. the pictures here are from www.movingart.tv and are covered by whatever rights that site asserts.

Friday, January 6, 2012

bee-ing a foster parent with zombies

Prof. Robin Owen
While reading about the zombie-making fly Apocephalus borealis (see my previous post) I found that some of the basic research on the fly and its native hosts, the bumblebees, was done by Prof. Robin Owen at Mount Royal College in Alberta. Robin and his students found that in southern Alberta, the fly parasitized a fairly large proportion of bumblebees of several species. Up to 20% of workers and a higher percentage of males had fly larvae. This work tells us that the fly is present in Canada and reasonably abundant.

Previous work showed that the fly was present in BC, Ontario, New Brunswick, and Nova Scotia. It's probably in the other provinces too but no one has looked for it. All of this tells us that Canada may not be immune to the problems this fly presents for honeybees, and the problems it may present for native bumblebees.

However, I don't like always being the bearer of bad news, so here is a wonderful CBC radio interview with Robin Owen about the "Bumblebee Rescue and Foster Parent Program" of the Calgary-based Community Pollinator Foundation. If you're in Alberta and you want to be a bumblebee foster parent, this is for you!
"Die Hummel", 1893, Sebastian Lucius

Wednesday, January 4, 2012

Unintended Consequences II: a "safer" pesticide kills bees in new ways.

Beekeepers know that their hives are at risk when pesticides are sprayed anywhere nearby, and occasionally lose massive numbers of bees to unanticipated spray programs. But the problem seemed to be manageable even in the 1950's and 1960's when large scale use of highly toxic pesticides was at its peak.

Colony collapse disorder is a syndrome - a cluster of symptoms - not actually a single disease, so far as we know. In the last decade many beekeepers have discovered that their colonies suddenly drop in numbers to the point of collapse. Sometimes the dying bees are found, as in this amateur blogger's pictures. But it can be difficult to tell whether diseases, pesticides, or some other cause is responsible. What's clear is that there have been massive losses of honeybees for the last 10 years. This article has a chart showing that losses more than doubled in most parts of Canada in the last 5 years. This summer I bought honey from a farmer near Creemore, Ontario who was so discouraged he was thinking of getting out of beekeeping. He had lost 85% of his colonies last winter.

In my last blog I mentioned that a strange unintended consequence of large scale, industrial-level beekeeping may be serious harm to bumblebees. In this post, I want to talk about another unintended consequence of a well-intentioned change made by the pesticide industry about 20 years ago.

Nicotiana alata by Carl E. Lewis - CC 2.0
The "neonicotinoid" pesticides were created 20-30 years ago to reduce harms to birds and mammals from pesticides. The name means new-nicotine-like and is descriptive. Tobacco plants make nicotine not for your smoking pleasure but because it is toxic to insects. In fact 100 years ago tobacco extracts were sprayed on greenhouse plants as a natural pesticide.

Nicotine, and the neo-nicotinoid pesticides, bind to an important receptor in nerves. Insect nerves are more disrupted by this than nerves of mammals or birds, making these compounds fairly safe for you, your cat, or your budgie. As such they were a great advance over the older generations of pesticides.

We humans are rarely content with just some improvement; we want more and more. So the chemists modified neonicotinoids to be persistent (so a low dose would work longer) and soluble in water. This meant an even smaller amount could be applied as a coating on seeds and soaked up by the sprouting seedling. This meant no spraying, and even protection of all parts of the plant. As a result neo-nicotinoid pesticides are now the most popular and widely used commercial pest control substance, with billions of $$$ in sales each year.

treated corn seed
As a result, corn growers now find it almost impossible to buy commercial quantities of high-yielding corn varieties that are untreated. Almost all seed (99.8%) sold is treated with a combination of a fungicide and a neonicotinoid.

That's why the findings of a team led by Christian Krupke of Purdue University are so important. Prof. Krupke was called in when local beekeepers reported large bee die-offs around corn seeding time. Dead bees collected had measurable amounts of neonicotinoids. To determine if these could be a cause of death and how they might be getting into the bees, Krupke's team planted corn over two years using treated seeds and normal planting methods, as well as saved seed from the previous year (which was untreated).

Some of their results have been published online in the the journal PLoS One (available to anyone - click the link). They discovered that a lubricant used to keep the coated seeds from sticking to each other - talcum powder! - ended up highly contaminated with pesticides. The contaminated talc is blown away and ends up coating spring flowers and plants near the fields. This is the first way bees are exposed.

guttation drops, not dew
The second exposure comes when the corn seedlings are just up. Many plants exude small droplets of sap from leaf tips at night when the humidity is high, called "guttation drops". To you or me they look just like dew, but bees know that they are sweet and will collect them just like nectar first thing in the morning. It's been known for several years now that guttation drops from treated corn seeds are so toxic they kill bees in just hours. The risk to bees is highest in the first week after emergence.

The third point of exposure is one of the least expected. When corn "flowers", that is when the tassels mature, vast amounts of pollen is available. Beekeepers have observed for years that bees will avidly collect corn pollen. Krupke's team found that foragers bees from hives near fields of treated corn were bringing back large amounts of corn pollen with significant levels of neonicotinoids in it. This pollen goes to feed new larval bees and newly emerged nurse bees in the hive. Over the life of one young bee in the hive, she would consume an amount of pesticide equal to 1/2 of the lethal dose for bees. This might or might not be fatal, but Krupke et al's analysis of dead and dying bees found near their hives showed much higher levels of neonicotinoids than from healthy bees.

The fourth exposure method is not discussed much in their recent article. However in a talk I heard Krupke give at the North American Pollinator Protection Campaign (NAPPC) 2011 conference, he told us that his colleagues found significant amounts of neonicotinoids in soils that had not been exposed to treated seeds for 2 years. Some estimates suggest these compounds may have a half-life of 15 years or more in the soil. This means that in fields planted with treated seed for 3 years out of a typical 4 year crop rotation, the "steady-state" level of neonicotinoids in the soil could end up several times higher than what is put on in any year.

So there's bad news and there's good news. The bad news is that even when the corn is long gone, the same fields may be producing flowers contaminated with neonicotinoids. The good news is that some of the contamination can be removed by improving seeding techniques - control that talcum powder!

dead honeybees - Clement Kent, CC 2.0
As one person at the NAPPC conference pointed out, the simplest, least debatable step would be for the manufacturers of neonicotinoids to tweak their formulas so that the pesticides are less persistent. This would give them something new to patent and help protect the environment. We can only hope that Bayer, Monsanto, Syngenta, and Dow take this message to heart, before we have converted much of our agricultural landscape into a toxic mess that will last a generation.



Krupke, C.H., Hunt, G.J., Eitzer, B.D., Andino, G., and Given, K. (2012). Multiple Routes of Pesticide Exposure for Honey Bees Living Near Agricultural Fields. PLoS ONE 7, e29268.