Bees Use a Variety of Senses and Memory of Previous Experiences to Forage for Pollen, Research Suggests

CATCH THE BUZZ-Bee Culture    By Elizabeth Nicholls    November 28, 2016

A honey bee foraging for pollen. Credit: Dr. Elizabeth NichollsBees use a variety of senses and memory of previous experiences when deciding where to forage for pollen, research by the University of Exeter suggests.

The researchers believe pollen-collecting bees do not base their foraging decisions on taste alone, but instead make an “overall sensory assessment” of their experience at a particular flower.

Bees typically do not eat pollen when they collect it from flowers, but carry it back to the nest via special “sacs” on their legs or hairs on their body.

This makes it difficult to understand how bees judge whether the pollen a flower produces is nutritious enough for their young.

Indeed, researchers have been puzzled for a long time as to what exactly bees look for when they collect pollen from flowers.

Co-author Dr Natalie Hempel de Ibarra, expert in insect neuroethology at Exeter’s Center for Research in Animal Behavior, said: “It seems that bees don’t just respond to a single nutritional compound in pollen, such as crude protein content, but to a range of sensory cues in pollen and flowers.

“They also form memories for locations and types of flowers that they have visited which affect their foraging decisions.

“We need more research that considers the behavior and neurobiology of bees to understand when and why they prefer some plants and some pollen over others.

“A breakthrough in this area could advance our efforts in both biodiversity conservation and crop production.”

The review, published in the journal Functional Ecology, examines existing evidence on how bees use their senses, previous experience and — in the case of social bees — feedback from the nest to decide where to gather pollen.

First author Dr Elizabeth Nicholls, a former PhD student at the University of Exeter and now a Postdoctoral Research Fellow at the University of Sussex, said: “Our review is unique in considering pollen foraging from an individual bee’s perspective, asking which senses bees use to decide which flowers are worth visiting.

“In our review we suggest that although bees may taste pollen during collection and use this nutritional information to guide their choices, they are also likely to pay attention to the strong odor and visual appearance of both pollen and the flower itself.

“For bees that live together in colonies, information passed on from the other bees in the nest, either via chemical cues or even special ‘dances’, may also be important in influencing their pollen-collecting behavior.”

The University of Exeter is a major hub for bee and pollination research and currently advertising several postgraduate research projects.

The American Apitherapy Society

The American Apitherapy Society offers and shares information to educate those of you who seek an alternative form of health care referred to as Apitherapy.  Apitherapy encompasses the use of bee hive products including honey, pollen, propolis, royal jelly and bee venom.  Apitherapy is used to treat many illnesses and to alleviate pain from injuries both chronic and acute.  We are an organization reaching beyond traditional Western medicine helping others to help themselves in attaining better health through a holistic approach in harmony with the bee hive, a true gift of nature.

Rising CO2 Levels Reduce Protein in Crucial Pollen Source for Bees

CATCH THE BUZZ - Bee Culture Blog     April 13, 2016

WEST LAFAYETTE, Ind. – Rising levels of atmospheric carbon dioxide have reduced protein in goldenrod pollen, a key late-season food source for North American bees, a Purdue University study shows.

Researchers found that the overall protein concentration of goldenrod pollen fell about one-third from the onset of the Industrial Revolution to the beginning of the 21st century.

Previous studies have shown that increases in carbon dioxide can lower the nutritional value of plants such as wheat and rice – staple crops for much of the global human population – but this study is the first to examine the effects of rising CO2 on the diet of bees.

“Bee food is less nutritious than it used to be,” said Jeffrey Dukes, study co-author and professor of forestry and natural resources and biological sciences. “Our findings also suggest that the quality of pollen will continue to decline into the future. That’s not great news for bees.”

Native bee species and honeybees rely on flowering plants for energy and nutrition. While nectar is the primary energy source for bee colonies, pollen is the sole source of protein for bees. Pollen is essential for the development of bee larvae and helps maintain bees’ immunity to pathogens and parasites.

Goldenrod, a common North American perennial that blooms from late July through October, offers bees some of the last available pollen before winter. Bees that overwinter must store substantial amounts of pollen to rear their winter young. Declines in pollen protein could potentially threaten bee health and survival and weaken bees’ ability to overwinter on a continental scale, said Jeffery Pettis, study co-author and research entomologist with the U.S. Department of Agriculture’s Agricultural Research Service.

“A poor diet sets bees up for failure,” he said. “Previous research shows bees have shorter lifespans when fed lower quality pollen.”

The researchers noted, however, that this study only assessed pollen protein levels and did not look at the impact of protein reductions on bee health and populations.

“Our work suggests there is a strong possibility that decreases in pollen protein could contribute to declines in bee health, but we haven’t yet made that final link,” said Dukes, who is also director of the Purdue Climate Change Research Center housed in Discovery Park.

Dukes collaborated with a team led by USDA-ARS researchers to examine protein levels in historical and experimental samples of goldenrod pollen. They found that pollen protein levels dropped about a third in samples collected from 1842-2014, a period during which the amount of carbon dioxide in the Earth’s atmosphere rose from about 280 parts per million to 398 ppm. The greatest drop in protein occurred during 1960-2014, a time when atmospheric carbon dioxide levels rose dramatically.

A 2-year controlled field experiment that exposed goldenrod to a gradient of carbon dioxide levels from 280 to 500 ppm showed strikingly similar decreases in pollen protein, Dukes said.

“These data provide an urgent and compelling case for establishing CO2 sensitivity of pollen protein for other floral species,” the researchers concluded in their study.

Bees provide a valuable service to U.S. agriculture through pollination, contributing more than $15 billion in added crop value each year.

But a number of new and mounting pressures are crippling colonies and endangering bee populations. These threats include emerging diseases and parasites such as deformed wing virus, Varroa mites and Nosema fungi; a lack of diversity and availability of pollen and nectar sources; and exposure to a wide variety of pesticides. From 2006 to 2011, annual losses of managed honeybee colonies averaged about 33 percent per year, according to the USDA-ARS.

“Bees already face a lot of factors that are making their lives hard,” Dukes said. “A decline in the nutritional quality of their food source going into a critical season is another reason to be concerned.”

Elevated levels of atmospheric carbon dioxide – a building block for plant sugars -have allowed many plants to grow faster and bigger. But this growth spurt can dilute plants’ total protein, rather than concentrating it in the grain, resulting in a less nutritious food source.

Slowing the degrading effects of rising carbon dioxide levels on plant nutrition hinges on reducing carbon emission rates from deforestation and burning fossil fuels, Dukes said.

“The impact of carbon emissions on the nutritional value of our food supply is something people need to be aware of. This issue isn’t just relevant to honeybees and people – it will probably affect thousands or even millions of other plant-eating species around the world. We don’t yet know how they’ll deal with it.”

The study was published in Proceedings of the Royal Society B on Wednesday (April 13) and is available to journal subscribers and on-campus readers at

Researchers from Williams College, the Smithsonian Institution and the University of Maryland also co-authored the study.

The work was funded by the USDA-ARS.

Why Feed Pollen Patties?

Bee Craft B-kids  Facebook post   January 19, 2016

Why feed pollen patties?

The thing to understand about pollen or pollen substitute is that it is used to feed larvae. Remember, bee eggs don't eat and pupae don't eat but the larvae are dependent on a good supply of nutritious, high protein food and this involves pollen. The larvae are not fed pollen directly; nurse bees eat the pollen, usually in the form of bee bread (a honey and pollen mix) and it is this rich diet that allows them to produce the brood food that they feed to the larvae. They cannot do this without eating pollen.

If pollen or pollen substitute is available, this will encourage the colony to produce brood. It is not such a good idea to encourage brood rearing in Autumn but it is an excellent idea in late January or February.

If you want to encourage your bees to produce lots of brood, especially if your apiary is in an area where there isn't much early pollen, then feed pollen patties in late January or through February when the queen is beginning to lay eggs ready for the new season.

(Taken from the B Kids pages in BeeCraft magazine, February 2016 issue)
Photo: Eric Lanning

The Pollen Basket

Honeybee Conservatory 

A Bee and Her Basket: Do you know what is a pollen basket?  Hmmm…  Well, have you ever noticed that some of the bees you see flying have these orange or yellow clumps on their hind legs?

If you haven’t, they look like this.

That orange mass on her leg is her basket. It is pollen that she has gathered from flowers she has been visiting during her foraging about. Female bees provision their offspring with pollen (mixed with a little nectar), which means they have to visit numerous flowers (sometimes 100 plus per trip!) to gather enough pollen to feed each offspring that is produced. It would be incredibly inefficient for them to have to travel back to their nest after visiting each flower. So, to be more efficient female bees have a special apparatus for holding and transporting pollen. The pollen collecting apparatus in apid bees, which include honey bees and bumblebees, is commonly called a ‘pollen basket’ or corbicula. This region is located on the tibia of the hind legs and consists of hairs surrounding a concave region. After the bee visits a flower, she begins grooming herself and brushes pollen gathered on her body down toward her hind legs and packs the pollen into her pollen basket. A little nectar mixed with the pollen keeps it all together, and the hairs in the pollen basket hold it in place.

Other bees have a similar apparatus, only it is called a scopa. This basket can be located on the hind legs and/or the ventral side of their abdomen. Look at the abdomen of the bee in the photo below:

Check out the furry legs on this cactus bee:

You may be wondering…’well, what is the difference between a pollen basket and the scopa?’ The main difference is that the pollen basket is a concave region surrounded by coarse hairs, whereas the scopa is just a region with a dense mass of specialized hairs (setae). But, both pollen baskets and scopa do the same job…transport pollen.

Now that spring is here, go out and check out the bees and look at their hind legs and their abdomen. If you see large pollen loads like these, or you see a bee that looks like she is covered with pollen, you know she has been working hard!

Guest post by entomologist Anna D. Howell of Anna’s Bee World.

(Note: This was originally posted on Honeybee Conservatory on April 2, 2011.)

Pesticides Found in Most Pollen Collected from Foraging Bees in Massachusetts

ABJ Extra    July 24, 2015

Boston, MA -- More than 70% of pollen and honey samples collected from foraging bees in Massachusetts contain at least one neonicotinoid, a class of pesticide that has been implicated in Colony Collapse Disorder (CCD), in which adult bees abandon their hives during winter, according to a new study from Harvard T.H. Chan School of Public Health.

The study will be published online July 23, 2015 in the Journal of Environmental Chemistry.

"Data from this study clearly demonstrated the ubiquity of neonicotinoids in pollen and honey samples that bees are exposed to during the seasons when they are actively foraging across Massachusetts. Levels of neonicotinoids that we found in this study fall into ranges that could lead to detrimental health effects in bees, including CCD," said Chensheng (Alex) Lu, associate professor of environmental exposure biology in the Department of Environmental Health at Harvard Chan School and lead author of the study.

Since 2006, there have been significant losses of honey bee colonies. Scientists, policymakers, farmers, and beekeepers are concerned with this problem because bees are prime pollinators of roughly one-third of all crops worldwide.

Previous studies analyzed either stored pollen collected from hives or pollen samples collected from bees at a single point in time. In this study, the Harvard Chan School researchers looked at pollen samples collected over time--during spring and summer months when bees forage--from the same set of hives across Massachusetts. Collecting pollen samples in this way enabled the researchers to determine variations in the levels of eight neonicotinoids and to identify high-risk locations or months for neonicotinoid exposure for bees. To do so, the researchers worked with 62 Massachusetts beekeepers who volunteered to collect monthly samples of pollen and honey from foraging bees, from April through August 2013, using pollen traps on the landings of beehives. The beekeepers then sent the samples to the researchers.

The researchers analyzed 219 pollen and 53 honey samples from 62 hives, from 10 out of 14 counties in Massachusetts. They found neonicotinoids in pollen and honey for each month collected, in each location--suggesting that bees are at risk of neonicotinoid exposure any time they are foraging anywhere in Massachusetts.

The most commonly detected neonicotinoid was imidacloprid, followed by dinotefuran. Particularly high concentrations of neonicotinoids were found in Worcester County in April, in Hampshire County in May, in Suffolk County in July, and in Essex County in June, suggesting that, in these counties, certain months pose significant risks to bees.

The new findings suggest that neonicotinoids are being used throughout Massachusetts. Not only do these pesticides pose a significant risk for the survival of honey bees, but they also may pose health risks for people inhaling neonicotinoid-contaminated pollen, Lu said. "The data presented in this study should serve as a basis for public policy that aims to reduce neonicotinoid exposure," he said.

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A Comparative Test of the Pollen Substitutes

Scientific Beekeeping     By Randy Oliver 

The growth and health of honey bee colonies is primarily dependent upon the availability of high-quality pollen. Pollen and its fermented form, beebread, is the colony’s primary source of protein, lipids, vitamins, minerals, and sterols [1].

When there is a dearth of quality pollen, colonies suffer [2]. Broodrearing comes to a halt and the nurses may cannibalize eggs and larvae. Colonies stop growing or go downhill. Protein-starved colonies are unable to hold their own against parasites and pathogens; diseases set in. Inadequate protein nutrition in late summer and fall leads to poor wintering and colonies unable to make grade for almonds.

To mitigate the above problems during times of pollen dearth, beekeepers...


Bees Have the Most Amazing Legs

The Yorkshire Post   By Andrew Brown   February 28, 2015

The honeybee has developed to make the fullest use of every part of its body, with many parts doing two jobs at once.

Legs are a handy tool in the pollen race. 

Bees have the most amazing legs. Not, you understand, that I’ve taken a fancy to them. I may be getting old and developing eccentricities but that would be a step too far. It is rather that the more I discover about what they do with them the more I am hugely impressed.

We humans have evolved so that our legs do one job pretty well. They take us from place to place and hold us up, but they don’t have a sense of smell. Indeed, the very idea seems absurd.

But honeybees have developed to make the fullest possible use of every micrometre of their bodies. Almost every part of their anatomy seems designed to do two jobs at once.

If a bee needs to smell something it can do so through its antennae but it can also detect chemical odours through its feet. Since bees send chemical messages that help them do things like recognise each other and know whether their Queen is strong, this also means that bees are talking to each other via their legs.

They also get messages that way about where to find food. Most people have heard of the honeybee waggle dance. This famously lets one bee do a figure of eight dance which tells other bees which direction to go to find a food source, how far away it is and what plan there.

What few people realise is that the dance is done in the dark. Bees can’t see the figure of eight that the dancing bee is making. Remarkably it is their legs that get the message. They feel the vibrations that are being made on the wax comb where the bee is dancing and, in the pitch black interior of the hive, this is enough for them to be able to learn where they need to fly.

When they arrive at the source of food the bee can be left with a bit of a problem. There may be lots of pollen on the plant but it isn’t exactly easy for a flying insect to carry back great quantities of food.

The solution to this problem is beautifully simple. Honeybees have a basket on their back legs and they can fill that basket with pollen, pack it down tightly and use it to bring the protein and vitamins that they need back to the hive. This ability has clearly evolved over millions of years to prevent them forgetting their shopping bag.

When they arrive back at the hive you can see the pollen. It comes in different colours according to the time of year and the source of the food. Late in the season my bees were bringing back yellow pollen from Himalayan Balsam. In high summer it was more orange and may have come from dandelions - an excellent source of pollen and nectar.

At the start of spring I hope they will be going to the plentiful hazelnut trees in our local hedgerows. These are pollinated by the wind and so have no nectar but they are full of protein rich pollen and that is invaluable early in the year.

The operative word is hoping. Early spring is the really risky time for honeybees. They can usually get through the cold alright. But by spring they need to start breeding and that takes a lot of energy at exactly the time when they have used up the bulk of their winter stores.

The old tired bees that have lived through the winter have to fetch enough food to raise new energetic bees to replace them. There are occasional days when I understand exactly how they feel.

Over the next few weeks I will be looking at the rear legs of my bees with some nervousness. If the weather is dry and it’s warm enough, and it isn’t too windy, then they’ll be out there. And if I see enough of them coming back with brightly coloured sacks full of pollen on their back legs then I’ll know everything is going to be alright and they’ve come through the worst. They’ll be ready to take on another year and so, I trust, will I.

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Pollen DNA Reveals Honey Bee Foraging Habits

Entomology Today   January 13, 2015

Exactly what plants do honey bees visit on their daily forages for food? A research team from Ohio State University has found that the answer lies in the pollen collected by the bees, and they have developed a new method that utilizes DNA metabarcoding to analyze pollen to determine its origin. Their new protocol has been published in the journal Applications in Plant Sciences.

“Understanding honey bees’ pollen preferences can provide insights to what a colony needs and help improve the quality of foraging habitats,” said Dr. Chia-Hua Lin, one of the co-authors.

Their work should provide other researchers with a foundation for uncovering information from pollen DNA, and it will also enable bees to do some environmental science fieldwork.

“A honey bee colony is like an army of research assistants — thousands of enthusiastic, flying research assistants that work all day and trespass with impunity,” said Doug Sponsler, another co-author. “While foraging each day, bees are unknowingly monitoring plants in their surrounding landscapes, some hard to reach by researchers, and collecting valuable data in the form of pollen. They can also serve as bioindicators of pollution and pesticides.”

According to his colleague and co-author Rodney Richardson, traditional methods of analyzing pollen data under the microscope suffer from being difficult, slow, and often imprecise.

“There’s a huge bottleneck in the workflow because ultimately every sample needs the undivided attention of one expert behind a microscope,” Richardson said.

DNA metabarcoding is a promising alternative because it allows rapid identification of the genera or even species present in a mass DNA sample of multiple organisms. The technology has been gaining popularity across many fields of biology, and Richardson and colleagues are among the first to apply it to pollen analysis.

“It’s a first attempt that lets other researchers know what to expect, using the ITS2 marker in particular,” said Richardson.

Metabarcoding resulted in higher sensitivity and resolution, and identified twice as many plant families than microscopic analysis of the same pollen samples. However, it lacks the ability to quantitatively assess the relative proportions of each pollen type, something that will need to be addressed in future advancements.

For now, a combination of traditional microscopic analysis with DNA metabarcoding offers a deeper look into bee foraging behavior than either method alone. For scientists, this is only the beginning of uncovering the secret life of bees. For the bees, it is only the beginning of their work as research assistants.

Read & Comments at:

Read more at: Application of ITS2 Metabarcoding to Determine the Provenance of Pollen Collected by Honey Bees in an Agroecosystem

Bee Pollen Diet

By Dr. Patrick Fratellone, MD RH (AHG) FIM
FACC, check out his blog at

I always knew it was a power house of
protein, amino acids, vitamins, and minerals.
There are great books on Honey, Propolis,
Pollen and Royal Jelly.

More Problems for Bees; We've Wiped Out Their Favorite Plants   By Diana Gitig   November 25, 2014 

Pollen samples from old museum specimens indicate bees' favorite meals are gone.

That orange blob on the bees legs is all pollen, saved for a future meal. (Credit: CA Dept of Food & Ag)Bees are disappearing—that much is certain. What's unclear is why. Pathogens and pesticides have been posited as potential causes, as has the loss of bees' preferred floral resources. This last reason has intuitive appeal: wildflowers are disappearing because of agriculture, and bees rely on the pollen and nectar in flowers, so the loss of flowers should be causing the loss of bees.

But a demonstration of this seemingly simple idea has been hard to come by. Different species of bees rely on different plants—the bee species that are disappearing have never been analyzed in terms of taste for the plants that are disappearing to see if they match up. And, once the bees or plants are gone...


Related article:

Diet Affects Pesticide Resistance In Honey Bees

Science Today    Source: Penn State     November 3, 2014

Feeding honey bees a natural diet of pollen makes them significantly more resistant to pesticides than feeding them an artificial diet, according to a team of researchers, who also found that pesticide exposure causes changes in expression of genes that are sensitive to diet and nutrition.

"Honey bees are exposed to hundreds of pesticides, while they are foraging on flowers and also when beekeepers apply chemicals to control bee pests," said Christina Grozinger, professor of entomology and director of the Center for Pollinator Research, Penn State. "Our study demonstrates that exposure to non-lethal doses of at least two of these pesticides causes large changes in the expression of genes involved in detoxification, immunity and nutrition-sensing. This is consistent with results from previous studies that have found that pesticide exposure compromises bees' immune systems. Furthermore, our study reveals a strong link, at the molecular level, between nutrition, diet and pesticide exposure."

Exploring this link further, the researchers found that diet significantly impacts how long bees can survive when given lethal doses of a pesticide.

"This interaction between pesticide exposure and nutrition is likely what's at play in our finding that feeding bees a complex diet of pollen -- their natural diet -- makes them significantly more resistant to lethal doses of a pesticide than feeding them a more simple, artificial diet," said Daniel Schmehl, postdoctoral researcher, University of Florida.

To determine the impact of pesticide exposure on gene expression patterns in honey bees, the scientists first fed one of two miticides -- coumaphos or fluvalinate, the two most abundant and frequently detected pesticides in the hive -- to bees for a period of seven days. On the seventh day, the researchers extracted RNA from the bees, attached a fluorescent marker to the RNA and examined differences in gene expression patterns -- indicated by changes in patterns of fluorescence -- between the pesticide-treated bees and the control bees.

"We found significant changes in 1,118 transcripts -- or pieces of RNA -- among the bees that were fed either of the two miticides compared to the control group," said Schmehl. "These transcripts included genes involved in detoxification, immunity and nutrition."

Based upon the results, the team performed several subsequent analyses aimed at understanding the impact of pesticides on honey bee physiology. One of these subsequent analyses examined the susceptibility of bees to pesticide stress after consuming a pollen diet or an artificial diet -- either a soy protein or no protein diet. The team fed the bees these diets while simultaneously feeding them a lethal dose of the pesticide chlorpyrifos, an insecticide that is frequently used to control pests in agricultural crops and commonly detected in honey bee hives. They then recorded bee mortality daily for each of the treatment groups for a period of 16 days.

The researchers found that the bees that were fed a pollen-based diet exhibited reduced sensitivity to chlorpyrifos compared to the bees that were fed an artificial diet.

The results appear in the online issue of the Journal of Insect Physiology.

"This is the first time such a strong link between pesticide exposure and diet has been demonstrated at the molecular level, and the first time the effects of artificial versus natural diets have been explored in terms of resistance to pesticides," said Grozinger. "Diet and nutrition can greatly impact the ability of bees to resist pesticides, and likely other stressors. However, agriculture and urbanization have reduced the amounts and diversity of flowering plants available to bees, which likely nutritionally stresses them and makes them more sensitive to these other stressors. If we can figure out which diets and which flowering plants are nutritionally optimal for honey bees, we can help bees help themselves."

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Bee Products Honey, Propolis, Pollen May Help Treat Depression

Apitherapy News   Posted by Editor October 10, 2014

Total monoamine oxidase (MAO) inhibition by chestnut honey, pollen and propolis

Journal of Enzyme Inhibition and Medicinal Chemistry, October 2014, Vol. 29, No. 5 , Pages 690-694Monoamine oxidase (MAO) inhibitors are generally used in the treatment of depressive disorders and some neurodegenerative illnesses, such as Parkinson’s disease and Alzheimer’s disease.The aim of this preliminary study was to investigate the MAO [MAO (E.C.] inhibiting effect of various apitherapeutic products, such as chestnut honey, pollen and propolis...

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Why Aren't We Growing More Willows as an Abundant Source of Pollen for Bees?

Crops for Energy  By Kevin Lindegaard    September 12, 2014

Willows are sometimes called the Easter Tree as they come into bloom early in spring. Male varieties can be particularly showy and produce prolific displays of golden catkins. They aren’t just nice to look at – they provide a lifeline to foraging bees by providing an abundant source of pollen and nectar when there aren’t many alternatives. This essential ecosystem service has so far been under exploited in commercial food production but could be a major fringe benefit of growing short rotation coppice (SRC) willow as an energy crop.

The valuable contribution that different willow species provide is widely recognised by bee keepers. Frank Greenaway a bee keeper in Carmarthenshire has planted willows to help his bees through the late winter lean period. He explained why a plentiful supply of early pollen is so important:

“The adult bees feed a mixture of pollen and nectar to their grubs. It is the protein content of the pollen that they need to grow from egg to adult bee, nectar only gives them energy.   Adult bees eat a lot of nectar to enable them to keep warm and fly but actually eat very little pollen as all their growing is complete.   When a colony gets going in the spring the queen starts laying eggs like mad and the demand is for pollen to feed the grubs – this can be in February or even earlier in mild years – it is usually the availability of fresh pollen (and the odd day above 12 degrees C to allow them to collect it) that is the controlling factor. A healthy hive normally has some reserves of honey even at the end of winter but they never seem to have enough pollen”.

In the face of the decline in pollinator populations (there has been a 54% fall in honeybee hive numbers in England between 1985 and 2005), it’s high time that this potential was recognised and utilised by the wider farming and horticulture industries. Early pollen derived protein from willow could be key to building up insect population numbers and influence the level of pollination in both food crops and wild plant populations later in the season.   Currently around 20% of UK cropland is covered by insect pollinated crops (such as apples, plums, pears and oilseed rape) and the value of pollination to UK agriculture has been estimated at £400 million.

It’s possible that SRC willow could be planted in conjunction with food crops and provide essential pollination services. A quick trawl of the web indicates that the source is plentiful and quality of protein in the pollen is good – very good. Various online sources suggest that willows can yield 1,500 pounds of pollen per acre (1.68 tonnes per hectare). This sounds like an awful lot but is not as fanciful as you might imagine. A mature stand of SRC may have around 400 or more catkins per stool and based on a stocking rate of 15,000 plants per hectare that’s 6 million catkins. Each of these catkins would have to produce just 0.28 grams of pollen. To put that into context that’s a lot less than a tenth of a teaspoon of sugar.

A typical honey bee colony consisting of around 20,000 bees collects around 57 kg of pollen per year.  If we assume a pollen yield from male SRC willow catkins of 1.68 tonnes/year, a 1 hectare plantation could potentially provide enough pollen to support almost 30 colonies, that’s 600,000 honey bees!

The quality of the protein seems to vary between species. The American pussy willow (Salix discolor) has a crude protein content of 21.9% whilst the crack willow (Salix fragilis) is 14.8 – 15.1%. Anything above 20% is considered a good pollen source. Research suggests that bumblebees reared on high quality pollen result in larger workers that are more efficient at nectar collection, can fly in cooler temperatures, can collect from deeper flowers and may be less prone to predation.


As there are around 350 species of willows worldwide and countless hybrid combinations the odds of being able to actively select for increased pollen yield and quality are high. The UK SRC willow breeding programme has created crosses involving around 55 species of Salix, many of which have a large displays of male catkins. Until now the selection has been based on biomass yield rather than gender, pollen yield and crude protein content. As a result most of the varieties available are females that flower in Jan-Feb. However, the selection criteria could be expanded to look for male genotypes that provide a wealth of pollen at crucial times of the year – a few weeks in advance of key food crops grown in the UK.

The table below shows the time when different willow species and cultivars come into flower in the UK. Many of these varieties have already been used in breeding and have produced male genotypes with abundant pollen.

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Why Honey Bees Forage in California Poppies

Bug Squad - Happenings in the Insect World   By Kathy Keatley Garvey    3/18/14

When you see honey bees foraging on the California poppy, the state flower, they're not there for the nectar.

They're there for the pollen.

"California poppies provide only pollen--no nectar," native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, told the Pollinator Gardening Workshop last Saturday on the UC Davis campus. Thorp was one of the featured speakers at the event,...


Visit the Kathy Keatley Garvey Bug Squad blog at:

About that Pollen...

Bug Squad - Happenings in the Insect World   By Kathy Keatley Garvey   1/31/14

Why is that in a honey bee colony, workers can carry pollen but not the queen?

Well, scientists from Michigan State University and Wayne State University have discovered the answer.

They've isolated the gene that's responsible for leg and wing development, according to a news brief in Entomology Todaypublished by the Entomological Society of...


Visit the Kathy Keatley Garvey Bug Squad blog at:

European Parliament Votes Pollen is Part of Honey

 PHYS.ORG   1/15/14

After years of wrangling and a ruling by the EU's top court, the European Parliament agreed Wednesday that pollen is a constituent of honey and not an added ingredient.

The distinction may seem arcane but it has important implications for the industry since it determines how honey jars are labelled when it comes to levels of  from genetically modified plants.

Purity is a key selling point for honey and a label warning consumers it contained GMO pollen might deter buyers anxious to avoid foods that have been genetically altered.

Lawmakers voted 430 for and 224 against to define "pollen as a natural constituent of honey, rather than an ingredient...

Read more at:


Honey Bee Medicine & the Apothecary

Burdock & Rose   By Lisa Rose Starner  5/3/13

Honey Bees are the Earth’s first and best herbalists. They flit from flower to flower; pollinating and as they do so they collect the plant’s magic pollen dust which then gets imbibed into deliciously healing honey. Bees also collect resin from trees to create propolis, which repairs cracks in their hives and is also a useful human medicine.

Honey bees are the magic link to our food system and are the proverbial canary in the cave when we think about health and balance in our ecosystems...


Where the Yellow Pollen Came From

Bug Squad - Happenings in the Insect World   By Kathy Keatley Garvey 2/18/13

Beekeepers who watch their bees return to their hives with pollen loads like to guess the origin of the pollen. Red, yellow, blue, white...

It's not unlike "What Color Is Your Parachute?" the job-hunting guide by Richard N. Bolles.

Sunday the bees foraging in flowering quince collected yellow pollen--heavy loads of pollen. They struggled with the weight and then headed home to help feed their colonies.  

Blue skies,...



Visit the Kathy Keatley Garvey Bug Squad blog at:
Visit the Kathy Keatley Garvey website at:

The Year 2040: Double the Pollen, Bees Happy, But Double the Allergy Suffering?

(The following is brought to us by the American Bee Journal.) 11/8/12


New study shows pollen counts will more than double in 28 years
ANAHEIM, CA. (November 9, 2012) – With this year's unseasonably warm temperatures and extended seasons, many have coined 2012 as being the worst for allergies. But if you thought your symptoms were worse than ever, just wait until the year 2040.

According to a study being presented by allergist Leonard Bielory, M.D., at the Annual Scientific Meeting of the American College of Allergy, Asthma and Immunology (ACAAI), pollen counts are expected to more than double by 2040.

"Climate changes will increase pollen production considerably in the near future in different parts of the country," said Dr. Bielory, ACAAI board member and fellow. "Economic growth, global environment sustainability, temperature and human-induced changes, such as increased levels of carbon dioxide, are all responsible for the influx that will continue to be seen."
In the year 2000, pollen counts averaged 8,455. Fast forward to 2040, and these counts are anticipated to reach 21,735. Researchers predict counts in 20-year increments up to the year 2100, and are incorporating various climatic factors in their models including weather patterns, changes in precipitation and temperature. The study, taking place at Rutgers University in New Brunswick, N.J., is ongoing to analyze various allergenic plants being grown in climate chambers mimicking future conditions.

While pollen counts will progressively increase over the years, the study also found the sneezing season will begin earlier every year.

"In 2000, annual pollen production began on April 14, and peaked on May 1," said Dr. Bielory. "Pollen levels are predicted to peak earlier on April 8, 2040. If allergy sufferers begin long-term treatment such as immunotherapy (allergy shots) now, they will have relief long before 2040 becomes a reality."

An earlier report by the same researchers demonstrated an increase in ragweed pollen in a section of the country, from Texas to the Canadian border, over the past 25 years. This was associated with an increase of ragweed pollen by two to three weeks as one moves north.

ACAAI allergists recommend allergy sufferers begin treating their symptoms with over-the-counter or prescribed medications two weeks before symptoms usually start. While there isn't a cure for allergies, immunotherapy is the only treatment that can prevent disease progression. It can also result in health care savings of 41 percent.
For allergy sufferers looking to combat seasonal symptoms, ACAAI suggests:
  • Know your triggers. You may think you know that pollen is causing your suffering, but other substances may be involved as well. More than two-thirds of seasonal allergy sufferers actually have year-round symptoms. An allergist can help you find the source of your suffering and treat more than just symptoms.
  • Work with your allergist to devise strategies to avoid your triggers, such as:
  • Monitor pollen and mold counts — most media report this information during allergy seasons.
  • Keep windows and doors shut at home, and in your car during allergy season.
  • Stay inside during mid-day and afternoon hours when pollen counts are highest.
  • Take a shower, wash hair and change clothing after being outdoors working or playing.
  • Wear a mask when doing outdoor chores like mowing the lawn. An allergist can help you find the type of mask that works best.