Underrated Beneficial Arthropods Part 1: Pollinators

The world of beneficial arthropods (insects and their relatives) far exceeds some of the common critters that we often associate with this category. Many of them perform vital functions in our own yards, gardens, and ecosystems all over the world. A very small sliver of all arthropods are considered pests of any kind though there are certainly some pretty devastating pests in this category. Most of these other organisms are either providing benefits or maintaining important ecosystem functions. They are often overlooked, as some of the more charismatic ones (like butterflies, bees, mantids, and lady beetles) take most of the spotlight. These other not-so-glamorous beneficial arthropods are just as important as the more famous ones, and often perform many tasks that go unseen and underappreciated.

I wanted to talk about each group of common beneficial arthropods (Pollinators, Natural Enemies, and Nutrient Cyclers), but as I was writing, I admittedly got a bit carried away. So in order to prevent this blog post from being extremely long, I decided to split this into 3 parts. Stay tuned for the next installments in my spring and summer GP blog posts. In the meantime let’s dig into some under-appreciated pollinators.

Underrated Pollinators

Goldenrod Soldier Beetle ( Chauliognathus pensylvanicus) feeding on pollen. Photo: Abiya Saeed

Ah yes, pollinators! Many people consider this their favorite category of beneficials (because very few things are as striking or charismatic as a bee or butterfly sipping nectar from a flower). This is also one of the first groups that come to mind when people think about beneficials in general. The classic image of a monarch butterfly or a honey bee on a flower is often associated as the representative image of this group. That being said, honey bees are just one example of the over 20,000 bee species that are found worldwide. But this group far exceeds butterflies and bees- and some of the less charismatic critters often get an unfair reputation, or just a lack of awareness about what they do. For a variety of reasons, including their anatomy, efficiency, abundance, and direct economic impact, bees are considered the most important pollinators. But many other animals are also great pollinators, some of which are the sole pollinators of certain plant species. In fact most arthropods that visit flowers have the potential to move pollen around, making them possible pollinators. But since I don’t have time to write a whole book’s worth of information into this blog post, I will focus on a few of the larger groups of these less famous pollinators. If you are interested in doing a deeper dive into the world of beneficial arthropods, I will include some resources at the end.

Flies

Flies (order: Diptera) are a huge group of insects, with over 110,000 described species in 150 different families. This group spans a wide variety of very well-known groups like house flies [Muscoidea] and mosquitoes [Culicidae], to not so well-known groups like stalk-eyed flies [Diopsidae] and long-legged flies [Dolichopodidae]. They encompass nearly all biomes and have a broad range of functional groups including predators, parasites, decomposers, and pollinators. In fact, some studies consider flies to be the second most important flower visitors after bees.

Green Bottle Fly (Lucilia sp.) on a Prickly Pear (Opuntia sp.) Photo: Abiya Saeed

According to a literature review by Cook et al. (2020): flies from 86 different families have been reported to visit over 1100 plant species. These flower-visiting fly species also include some that have important potential for crop pollination and have been recorded to visit many horticultural crops. This includes commonly known pollinating flies, e.g., bee flies [Bombyliidae], hoverflies [Syrphidae], and flower flies [Anthomyiidae]. But some flies we don’t usually associate with this role such as blow flies [Calliphoridae], flesh flies [Sarcophagidae], and horse flies [Tabanidae], and some that many may never have heard of such as nose flies [Rhiniidae] and march flies [Bibionidae], are included. Some species are even considered to have potential as managed pollinators, a role that we most commonly associate with honey bees and some other bee species.

Fun fact: only female mosquitoes need a blood meal in order to reproduce, whereas male mosquitoes feed on nectar, making mosquitoes pollinators! In fact, mosquitoes have been studied as pollinators of orchids, like the Blunt-leaf Orchid, Platanthera obtusata, among other plants.

Moths

We all know butterflies and moths (order: Lepidoptera) are well-documented flower visitors and important pollinators. Despite this, butterflies often get most of the limelight and attention from the general public while many moths often end up being overlooked. Even though moths make up nearly 90% of the over 160,000 described Lepidoptera species, there is a disproportionate amount of research that has historically been conducted on them when compared with butterflies. It has also been demonstrated that moths are the most important nocturnal pollinators, which is fairly intuitive when you think about their nocturnal foraging biology. A study conducted in Sussex by Anderson et al. (2023) demonstrated that moths had higher pollen deposition rates on bramble species indicating that they are more efficient pollinators of brambles than their diurnal counterparts. This has implications for the importance of moths in other plant groups as well, as new research continues to be conducted.

Clearwing Moth (Hemaris sp.) Photo: Steven Katovich, Bugwood.org

Fun fact: My favorite story to tell about plant-pollinator interactions is of Darwin’s Star Orchid (Angraecum sesquipedale). Charles Darwin was sent a sample of this striking orchid from Madagascar in 1862. Upon examination he found that the nectar tubes were 30 cm (~12 inches) deep! Based on this, Darwin hypothesized that it would take something that has a really long tongue to be able to access that nectar but nobody believed there could be such an insect and he was ridiculed by other scientists. In 1867 Alfred Russel Wallace examined the orchid and predicted there must be a moth in Madagascar that can reach this nectar in order to pollinate the plant. But no moth had ever been discovered which had a proboscis (a coiled and elongated mouthpart of butterflies and moths that is used to suck up nectar) that long. It wasn’t until decades later in 1903 a moth meeting these specifications was discovered. Aptly named in honor of the scientist who predicted its existence, Wallace’s sphinx moth (Xanthopan praedicta) also known as the ‘predicted moth’ has the longest proboscis (sometimes referred to as a tongue, though it is not quite a tongue) of any insect. This just demonstrates just how amazing plant and insect interactions and coevolutionary relationships truly are!

The Star Orchid alongside the ‘Predicted Moth’! Photographed by Robert Clark for Evolution

Wasps

Wasps are in the order Hymenoptera, shared with bees and ants. They often have a bad reputation due to a few particularly aggressive social wasp species that most of us have likely had an unfortunate interaction with. That being said, the wasp group is extremely large, diverse, and species-rich. With over 103,000 described species in the category (and scientist estimates stating that the actual number could be in the millions), wasps span a lot of crucial categories of beneficials including parasitoids, predators, and pollinators.

Many wasp species resemble bees and it can be easy to confuse them for each other when they are visiting flowers. The major differences between the two are the thread-like waist that wasps have, and their less-hairy sometimes shiny, overall appearance. In addition most wasp species are primarily carnivorous, feeding on insects and other sources of meat for their protein needs, making them a great resource for deterring common garden pests (stay tuned for more on that in the next part of the Underrated Beneficials series). Even though most of these wasps are carnivorous, they supplement their diet with sugars which they often get from nectar or honeydew produced by sap-sucking insects, e.g., aphids, and occasionally fruit.

White-Striped Black Mason Wasps ( Pseudodynerus quadisectus ) mating on a Goldenrod (Solidago sp.) Photo: Abiya Saeed

There are also some species of vegetarian wasps. A common example of these are the 300 species of pollen wasps (Masarinae) which, like bees, are nectar and pollen feeders (and many of which are important pollinators of certain plant species, such as the Water Leaf, Hydrophyllaceae).  Due to the fact that they have fewer hairs, wasps aren’t as efficient at pollination as bees, however, they can still be very important pollinators. Like bees, some wasps are generalist pollinators, visiting a wide-array of flowering plants, while others are specialists where a group of wasps relies on a group of flowering plants and vice versa. In these cases the pollination of those plants are reliant on these wasps.

Studies have shown that some generalist wasp species are better than some generalist bees at pollinating specific flowers. A 2018 study by Thomson examining the pollinators of the California Bee Plant (Scrophularia californica) showed that the western yellowjacket (Vespula pensylvanica) was a more effective pollinator in terms of pollen deposition when compared with honey bees and bumble bees. Some species of African pineapple lilies (Eucomis autumnalis and Eucomis comosa) and African milkweed (Pachycarpus grandifloras) are primarily pollinated by spider-hunting wasps (Pompilidae) in the genus Hemipepsis. Additionally over 100 species of orchids are reliant on wasps for pollination some of which use sexual mimicry to attract male wasps to flowers! And I would be remiss if I didn’t mention fig wasps (family: Agaonidae), who have been coevolving with their host plant for tens of millions of years. The fig (Ficus sp.) ‘fruit’ is actually an inflorescence (an enlarged stem with lots of little flowers inside). In order to pollinate those flowers, the female fig wasp squeezes into a small opening and moves around, laying her eggs in the ovaries of these flowers thereby spreading pollen from the fig that she was born in. The male offspring will remain in the fig while the new batch of females will emerge and look for a new fig in which to lay their eggs (see resources for more on this fascinating mutualism).

For more information on wasps as pollinators, check out the awesome article by Hooks and Espíndola, linked in the resources!

Fun fact: Sexual mimicry is used by some flowers to attract their pollinators. In these situations, the flowers use a combination of visual and chemical cues including mimicking the scent of specific female wasps and bees to attract males. An example of this can be seen in the wasp family Thynnidae, where male winged-wasps are searching for wingless females to mate with. When they stumble across the warty hammer orchid (Drakaea livida) they confuse it with a female thynnid wasp, because of the similar shape and scent, and try to mate with it. This process results in the pollen being deposited on the abdomen of the male wasp. As he goes to the next orchid in order to mate, the pollen is deposited on the new flower, resulting in pollination.

Beetles

Beetles (order: Coleoptera) are considered to be the largest insect order with over 350,000 described species, which makes up 25% of all known animal species on Earth! Like some of the previously mentioned orders, they include a large diversity of functional groups, including pollinators. Due to the incredible size of this order, they are considered to be the largest and most diverse group of pollinators with an estimated 77,000 flower-visiting species. In fact, based on pollen-covered specimens preserved in amber from 100 million years ago which is 30 million years earlier than the first records of bee pollinators, beetles are considered to be the first recorded insect pollinators! Even now they are considered to be vital pollinators of some of the most primitive flowering plant groups that still exist today, such as Magnolias.

Flower Longhorn Beetle (Analeptura lineola) on a Multiflora Rose (Rosa multiflora). Photo: Ansel Oommen, Bugwood.org

Although some beetles are specialists of certain plant groups ,especially those that are descendants of some of the earliest flowering plant groups including water lilies and magnolias, most are generalist pollinators and will visit a wide array of flowering plants. Some scientists even estimate that flower-visiting beetle species will visit 90% of all 350,000 flowering plant species. Beetle pollination is also essential for certain agricultural crops including Paw Paw (Asimina sp.) and the Atemoya (Annona x Atemoya).

For more information on the fascinating world of beetle pollination, check out the awesome article by Hooks and Espíndola, linked in the resources!

Fun fact: The process of cross-pollination that depends on beetles is referred to as ‘cantharophily’.

Resources

Cook et al. (2020). The Role of Flies as Pollinators of Horticultural Crops: An Australian Case Study with Worldwide Relevance. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7349676/

Anderson et al. (2023). Marvellous moths! Pollen deposition rate of bramble (Rubus futicosus L. agg.) is greater at night than day. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0281810

Hooks and Espíndola. (2017). Wasps, surprisingly cool pollinators. https://blog.umd.edu/agronomynews/2020/08/31/wasps-surprisingly-cool-pollinators/

The story of the fig and its wasp. https://www.esa.org/esablog/2011/05/20/the-story-of-the-fig-and-its-wasp/

Hooks and Espíndola. (2017). Beetles and Pollination.
https://blog.umd.edu/agronomynews/2020/06/29/beetles-and-pollination/

Bee Lawns: What’s all the buzz about?

A bee lawn is a way to benefit pollinators in our landscapes by providing additional floral resources, and often utilizes a mix of low-growing flowering plants in addition to turf species. Although flower gardens also provide flowering plants for pollinators, bee lawns can be multi-functional in their usability for recreational purposes with the added benefit of providing food for bees.

Habitat loss is one of the major factors implicated in the global declines of native bee species. Providing resources utilized by these critical pollinators can assist in mitigating this. Research through University of Minnesota has found 50 species of bees utilizing the flowers in bee lawns.

The purpose of bee lawns includes providing nutritious sources of nectar and pollen for pollinators, especially in urban environments, where these resources can often be scarce and difficult to find. Additional factors include recreational usability, and reducing inputs, e.g., irrigation, nutrients, weed control, and time spent mowing. Flowering plants suited for bee lawns have a variety of common characteristics including: low-growing and flowering heights, perennial life cycles, the ability to persist with turf species, and tolerance of mowing and foot traffic.

An important consideration is that bee lawns don’t necessarily mean weedy lawns or no-maintenance lawns, but instead require different types of management and serve different functions than traditional turfgrass lawns.

Not all bee lawns are created equal, and some work better than others.

Here are some turfgrass species that can work well for bee lawns:

Cool-season turf

A mix of fine fescues (which includes species such as: creeping red fescue, chewings fescue, hard fescue, and sheep fescue) are some of the best options for bee lawns due to reduced needs for inputs including irrigation, fertilizer, and weed controls, in addition to their compatibility with flowering plants. That being said, fine fescues do not tolerate heavy foot traffic, and may not be a suitable option for turf varieties in areas with heavy recreational use.

Kentucky bluegrass (KBG) is another option for bee lawns, though it requires higher maintenance (including more frequent irrigation and fertilizer inputs). KBG is considered an invasive species in some areas so do your homework.

Warm-season turf

Although there is limited research currently available for warm season turfgrasses and their compatibility with flowering plants specifically for bee lawns, certain species require lower inputs and could be a good option.

Centipede grass is a suitable option for a low-maintenance warm season turf species, and has been utilized in studies evaluating early-spring flowering bulbs as part of a lawn ecosystem for pollinators (see resources for more information).

Bermudagrass can also be used with flowering plants, though it has higher input needs than centipede grass. For more detailed information on warm season turfgrass species suitable to your geographic area and their respective input needs, I would encourage you to reach out to your local and regional extension offices.

Here are examples of flowering plants that can work well with turfgrass species:

Dutch white clover (Trifolium repens)

Dutch white clover (often referred to as white clover or clover) is a common occurrence in many lawns. Although some consider this to be a weed, white clover can provide several benefits including its adaptability to many soil types, the ability to withstand some shade and foot traffic, and the added benefit of being able to fix its own nitrogen. Like its name suggests, white clover produces white (and sometimes pink) flowers, and grows to a height of 4-6 inches. In addition to its hardiness, white clover is also an excellent source of forage for bees due to its long bloom time, and the great quality of nectar (high sugar content) and pollen (high protein content).

Dutch white clover flowers in a lawn (Photo: Whitney Cranshaw, Colorado State University, Bugwood.org)

Creeping thyme (Thymus praecox)

Creeping thyme is related to some of our favorite culinary herbs, and produces fragrant purple/pink flowers. It has a low growth habit (<6 inches) and can tolerate some foot traffic. It performs best in well-drained sandy or loamy soils, and is also considered to be drought tolerant and deer-resistant.

Self-heal (Prunella vulgaris ssp. lanceolata)

Self-heal is native to North America, Europe and Asia, and research from University of Minnesota has shown that 95% of the pollinators that visited the flowers were native bee species. It produces purple flowers and does well in a variety of soil types (with the exception of sandy soils) and in sun or partial shade.

Self-heal flowering with turfgrass (Photo: John D. Byrd, Mississippi State University, Bugwood.org)

Common violet (Viola sororia)

Violets are another flower that some consider to be a weed in home lawns. These spring blooming yellow, purple, and white flowers can be a good source of nectar for pollinators such as butterflies and bees. Violets grow to heights of 4-8 inches, and do well in a variety of soil types in addition to sun and shade.

Purple flowers growing in grass
Violets growing in a lawn (Photo: Sarah Eilers, Montana State University)

Other flowers

Additional low-growing flowers could also be great additions to bee lawns, including early spring flowering bulbs that can persist with turfgrass for multiple years, such as crocus and grape hyacinth (Muscari spp.), which have been observed to attract pollinating insects (especially honey bees).

For more information on the regional suitability of flowering plants to incorporate with turfgrass for bee lawns, contact your local extension offices for more information.

University of Minnesota’s Bee Lab has a lot of excellent information on bee lawns, their establishment, and the diversity of bees that visit them:
https://extension.umn.edu/landscape-design/planting-and-maintaining-bee-lawn#turfgrasses-for-bee-lawns-2939360

https://turf.umn.edu/news/if-you-build-it-who-will-come-evaluating-diversity-bees-flowering-lawns

Additional Resources:

https://www.canr.msu.edu/news/consider-a-flowering-bee-lawn-to-help-pollinators

https://extension.psu.edu/the-buzz-about-bee-lawns

Wisdom, M. M., Richardson, M. D., Karcher, D. E., Steinkraus, D. C., & McDonald, G. V. (2019). Flowering persistence and pollinator attraction of early-spring bulbs in warm-season lawns. HortScience, 54(10), 1853-1859.
https://journals.ashs.org/hortsci/view/journals/hortsci/54/10/article-p1853.xml

Larson, J. L., Kesheimer, A. J., & Potter, D. A. (2014). Pollinator assemblages on dandelions and white clover in urban and suburban lawns. Journal of Insect Conservation, 18(5), 863-873.
https://link.springer.com/article/10.1007/s10841-014-9694-9

Update on our bare-rooted perennial garden

Our south-facing pollinator garden.

Two years ago I installed a pollinator garden in early July. This goes against my recommendation to install plants in the fall, when roots have longer to get established and less stress is felt on the rest of the plant. But I wanted to see what would happen if I was careful to mulch well and keep it irrigated. Oh, and did I mention I was going to root wash every one of them? (Be sure to look at that process in the link from 2018.)

I reported on progress last year, and this year shows even more vigorous growth by nearly all the plants. Two of the three ‘Bandera Purple’ lavender died over the first winter, as they were marginally hardy (USDA 7-10) for our area. One straggler remains in the lower right hand corner of the photo below. The Agastache ‘Acapulco Red’ and the Verbena ‘Homestead Purple’ were planted near the front of the beds on both sides and while they survived the first year, they are now gone. My guess is that our cold snap in February 2019 wiped out those plants that were in less protected locations. Perhaps we’ll fill those spots in later with something more cold hardy, or just let the escaped Viola tricolor continue to colonize bare spots.

Overall, the garden is wildly successful in attracting hummingbirds and a variety of native bees and other insects.

The southwest garden is being colonized by violets that have hopped out of a nearby container. Wood chip mulch keeps the soil cool and moist.
The southeast garden with its invading strawberries (soon to be relocated). The tiny lavender in the back right corner is a rescue plant.

I still have a little work to do – I’m relocating the strawberry adjacent to the southeast garden so it stops invading the perennial bed. But after that I’m calling this garden finished.

Eggplants getting their buzz on

eggplantflower

I was checking my eggplants today, and watching the bumble bees getting busy with the large purple flowers. As they flew in, buzzing away, they landed on the flower and kept buzzing — but the note changed, dropping in pitch. The bumble bee hummed away for a while, then flew off to the next flower.

I was watching buzz pollination at work. Egg plants, and a lot of other flowers, don’t leave their pollen hanging out in the open where any ant or fly that happens by could eat it. Rather they wrap them up in little packages that, when vibrated at just the right rate by a buzzing bumble bee, sends the pollen shooting out, so that bumble bees, which pollinate effectively, can access the pollen, but other insects, that would just eat it all, can’t.

In the garden, it isn’t easy to catch a glimpse of the pollen spewing forth, but luckily there are videos. Thank goodness for youtube. Watch it, and next time you are in your garden and hear a bee land in the flower and suddenly change the tone of its buzz, know you are seeing — and hearing — buzz pollination at work.

Cross-pollination making you cross?

No, your cucumbers have not hybridized with your melons.

I’ve been fielding different versions of the same question a LOT lately.
Three different people have sent pictures of “cucumelons” telling me they planted cucumbers next to their melons, and now the cucumbers look strange, so they’re concerned that they have cross pollinated with the melons. One person planted what was supposed to be a red raspberry next to their yellow raspberry, but the new plant is producing yellow fruit, so they think that it must be cross pollinating with their yellow plant, causing the fruits to turn yellow. Not to mention similar queries about tomatoes, peppers, and watermelons. It seems like every time a piece of produce turns out looking differently than what people expect, they blame pollen from the plant next to it.

I’m sure the highly educated readers of The Garden Professors know this already, but to clarify, there is a very simple reason why you don’t need to worry about one plant pollinating another plant and changing the quality of your produce UNLESS you are planning on saving seeds to grow for the next year.

When a flower is pollinated and starts developing into a fruit full of seeds, it is only the seeds themselves that combine the genetics of the two parents to develop into something new. Everything else – the flesh of a tomato, or cucumber or melon or raspberry – is produced solely by the mother plant, and the daddy of those seeds inside doesn’t matter a bit. Think about when a woman is pregnant… the identity of the father of the child inside her doesn’t change the character of the skin of her belly.

If you want to save seeds of your plant for next year, it is another matter, and you should be sure to isolate or (better yet) hand pollinate different varieties of the same species from each other to make sure they don’t hybridize unintentionally. You still don’t need to worry about your cucumbers and melons, however – they won’t hybridize by chance in your garden. If a plant doesn’t produce the right colored fruit or flower, most likely it was just mislabeled at the nursery. Grow a strange looking cucumber, chances are it was left on the plant too long. Cucumbers are harvested and eaten when young and immature, leave them too long and they get… strange looking. No need to blame it on the melons next to them.

There IS one exception to this, one common plant in the garden where the source of pollen makes a huge difference in what you harvest: Corn. Corn is the exception because what we’re eating is the seed itself, not the fruit produced by the mother plant surrounding the seed. That’s why if your sweet corn gets a dose of pollen from the field corn the farmer is grown next door, it comes out starchy and not sweet.

It also makes breeding colorful corn for fall decorations REALLY fun… Because when you see a multicolored ears of corn like this from my garden last year:

multicolored corn
You can carefully pick out just the seeds showing the colors you like best, say the palest blues and pinks, sow them together the next year, and get something looking like this:

pink and blue corn
Or plant all the darkest kernels together and get this:

black corn

Are Pretty Flowers Useful?

Yesterday I had the opportunity to listen to Marla Spivak, a very highly regarded bee scientist, talk about how bees defend themselves from disease.  Very interesting stuff.  I took a lot of information away from the talk, two bits of which I want to share with you.

The first is a vocabulary word — propolis – go ahead, google it (I don’t think too much inappropriate stuff will pop up) – it’s an antimicrobial “ointment” which bees create from stuff like the resins on tree buds.

The second is that the number of bee colonies is the US has been going down in the US since 1945 for a number of reasons.  One of the most important of which is the fact that we like to kill flowers, such as dandelions and clover, which bees like, and then we plant crappy flowers – at least as far as the bees are concerned.  The whole crappy flower thing isn’t something that I’d spent much time thinking about, so it was kind of an ah-ha moment for me.

Here’s how it works.  People tend to like double flowers.  Double flowers usually occur because the male parts of the flowers – the parts which normally contain pollen – instead develop into petals.  It’s a mutation – very pretty – but it inhibits the flower from reproducing itself through seed and it certainly isn’t great for bees who rely on pollen for food.  So when we plant our gardens we are removing plants that bees may love because we consider them weeds.  Then we replace these flowers with what amounts to plastic fruit.  My opinion – this is probably more significant to the lives of both honey bees and native bees than whether we plant natives or exotics.

So let your yard go wild!  The bees will thank you.

Bees and Pesticides

I had the opportunity to read a disturbing post over at Garden Rant the other day about the insecticide clothianidin and how the EPA required its producer, Bayer, to run tests on the safety of using plants grown from seeds treated with clothianidin for bees.  Tests which were, apparently, never carried out appropriately.  This post sent me over to another site, AlterNet, which explained the problem in detail.  In a nutshell what happened is that the EPA asked Bayer to run some tests on how its new pesticide might affect bees. Bayer was unresponsive at first, but eventually did run some tests (which were not what you would call robust) which showed that bees did fine when flitting around in a field of plants which came from clothianidin treated seeds  – at least for as long as the test was carried out.

Then one of our commenters asked for our opinion, and heaven knows, I am always more than happy to offer my personal opinion!  So here it is.  I am extremely unhappy with both Bayer and the EPA in this instance.  They didn’t do what they were supposed to do.  It’s as simple as that.  Tests were supposed to be run to demonstrate that it is unlikely that clothianidin affects bees.  This wasn’t done in a reasonable period of time.  Period.  As long as stuff like this occurs nobody is going to trust the EPA or the chemical manufacturers.  In terms of whether the tests were sufficient (basically some hives in a field of treated plants), well, I would have liked to have seen more depth, but they didn’t seem to be bad studies.

The implication is that, because we don’t have enough testing, clothianidin could be causing bee colonies to collapse.  This goes hand in hand with the suspicion that imidacloprid is leading to colony collapse since both of these chemicals are neonicotinoids.  We know that these pesticides can get into flowers where bees come into contact with them.  The question is whether the bees contact enough to cause hives to collapse (There is no question that these chemicals, at some level, are poisonous to bees – just as almost anything can be poisonous to humans at a high enough dose – even water).

One thing that is lost in this discussion is that SEED TREATMENTS were being examined.  A seed treatment is when the seeds which are planted are treated with a pesticide (in this case clothianidin) to protect the seed itself and the young plant from insects.  As the plant grows the insecticide will break down and become diluted – And so it is probably not going to be present at high levels in pollen that the plant (which comes from the treated seed) produces.  Still, there is potential for this to happen and so it is best if the plants which come from the seed are tested – hence the EPA’s request.

Historically, there are pesticides which have clearly and unambiguously lain waste to bee hives, the most infamous of which was Penncap-M.  This was a unique pesticide because it was a microencapsulation of the very dangerous insecticide methyl parathion.  The microencapsulation process made this pesticide last longer, and made it somewhat safer to handle, but it also made the pesticide into tiny little beads – about the same size as, you guessed it, pollen.  In fruit trees in particular this stuff would become attached to the bees (just like pollen does) and you can imagine the disastrous results.  The answer was to limit the use of this poison to certain times of the year and certain situations when bees were not likely to be around.  Why wasn’t it just banned outright?  Because it worked well and, when used appropriately, it didn’t affect bees (Here I’m giving you the official line – In my opinion its use should have been even more restricted than it was).   Penncap-M is not closely related to the neonicotinoids chemically, though it does affect insects’ nervous systems as many insecticides, including the neonicotinoids, do.

You can count me as one of the people who suspect that the neonicotinoids have something to do with colony collapse.  I’m not a bee researcher — but it is easy to see how the use of these chemicals might weaken a hive to the point where mites or disease could come in.  One of the things that drives me a little nuts though are those people who think that banning neonicotinoids is going to save our bees.  It seems quite obvious at this point that these chemicals are definitely not the sole cause of the disease and perhaps not even one of the major contributing factors.  They essentially banned these pesticides in parts of Europe, and guess what?  They still have bee colonies collapsing.  An interesting side note is that historically large-scale losses of bees isn’t as odd as we might think – in fact, we might have seen this disease (CCD) before.  Perhaps even in the 1800s.  In short, it seems that the answer to this problem is not as simple as banning some pesticides (though restricting their use may be a piece of the solution).  I wish it were.

Bee studies, blogs, and biases

My original posting last Wednesday (“Ignorance and the so-called “bogus” bee study“) has generated some vigorous discussion, which is exactly what I hoped it would do. At some point, one of our readers posted the link on the original blog site, where it generated the following response:

“The issue on CCD and these studies that point to “causes” other than pesticides comes down to a question: What came first? The pesticides or the problem. Farmers almost always have the gut answer correct. In this case the farmers are the hundreds if not thousands of beekeepers who are certain that neonicotines are root cause of colony collapse disorder. I’m not a PhD, admittedly, but I’ve yet to read anything that points to an answer other than the pesticides.

“And for Linda to suggest that science can’t be “bought” at universities is an incredibly naive statement. I’m not saying Jerry was bought out, not at all. But I do think, overall, there’s a ton of pressure from the chemical industry for scientists to find an answer, any answer, that doesn’t point back directly to pesticides.”

I responded to this posting on the blog this morning, where it sat waiting for approval by the moderator:

“There are dozens of peer-reviewed studies on colony collapse disorder that can be easily accessed by anyone who is really interested in the science. Here’s a quote from a 2009 article:

“Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels), no single measure emerged as a most-likely cause of CCD.”

From “Colony collapse disorder: a descriptive study.”

Authors: Engelsdorp, D. van; Evans, J. D.; Saegerman, C.; Mullin, C.; Haubruge, E.; Bach Kim Nguyen; Frazier, M.; Frazier, J.; Cox-Foster, D.; Chen, Y. P.; Underwood, R.; Tarpy, D. R.; Pettis, J. S.

Available at: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0006481.”

Then….it was deleted.

For whatever reason, the moderator of this blog didn’t want to post my response. So I’ve reposted it above, and have a couple of other observations:

1) “Gut answers” aren’t science. Sure, gut feelings can convince researchers to explore some particular question, but they are inspirations – not necessarily answers. As my husband pointed out, people once had “gut feelings” that the earth was flat and that the sun orbited around the earth. Enlightenment happens.

2) Let’s see some specific examples where science has been “bought” at universities. I’m sure there are a few bad apples (especially in pomology – HA!), but to my knowledge none of my colleagues have pandered to chemical companies and falsified data for publication. This is a serious charge – and if it’s true, we all deserve to see hard evidence.

As always, feel free to post YOUR comment. We won’t censor you, even if you don’t agree with us.

Ignorance and the so-called “bogus” bee study

I’m angry.  Really, really angry.  And it’s all Kenny’s fault.

Kenny S., one of our long-time blog followers, alerted me to a blog posting dismissing a new study on colony collapse disorder (CCD). The post was devoid of any evidence of bogusness, other than a link to “great reporting” by New York Magazine. Aside from the general snarkiness of this article, we’re breathlessly informed that Fortune magazine (a hotbed of scientific inquiry) uncovered an unholy connection between the lead author (Dr. Bromenshenk) and Bayer.  That article recounts Dr. Bromenshenk’s sins, which include (1) accepting research money from Bayer, (2) not serving as an expert witness in a legal case against Bayer and (3) not studying every single possible cause of CCD.

Next I looked at the contested study, which is in an online journal.  Apparently none of the reporters/bloggers have bothered reading this, because they could easily discover the following:

1) there are 18 authors from many institutions, not just Dr. Bromenshenk and “Army scientists”;

2) the methodology was specific for protein analysis (not for pesticides nor any other nonliving factor);

3) funding was not provided by Bayer or any other corporation;

4) competing interests, such as Dr. Bromenshenk’s company, are openly acknowledged;

5) the article does not suggest anywhere that pesticides are blameless in CCD.

The body of the article is pretty technical and I’m not an entomologist. Still, this is in a peer-reviewed journal (albeit online rather than print).  You can see the review process and the list of academic reviewers if you were so inclined (as anyone who writes about science should be). Thus, qualified scientists (in addition to the 18 authors) find this to be a legitimate study.

Let’s look at Dr. Bromenshenk’s research history.  (For the record, I don’t know him and had never heard of him until yesterday.)  He’s published at least 26 scientific articles (in journals including Science) on various aspects of bee biology for the last 27 years.  To do these studies, he needs funding.  Guess what?  Universities don’t provide funding.  Magazines don’t provide funding.  Bloggers don’t provide funding.  Other than a handful of relevant government agencies (like NSF or USDA), most big grants come from corporations.  Like Bayer.

Now this is why I’m mad. There’s widespread perception among nonacademic types that corporate grant money “buys” results. That’s insulting. Most scientists do what they do because they love the thrill of discovery. There’s no thrill if you’ve rigged the results. Moreover, if you rig the results you’re going to be found out…eventually. A scientist with 27 years of credible, scientifically reviewed research is hardly a data rigger. And he’d have to convince 17 coauthors to go along with the scam.

Near the end of the Fortune article (and ignored by subsequent articles and blogging) was Dr. Bromenshenk’s efforts to get Bayer and the beekeepers to talk to each other. Though he was able to get Bayer to appoint a beekeeper advisory board (to assist with experimental design) in an effort to increase “trust and transparency” with the public, it hasn’t been terribly successful.

So here we have a man who’s devoted more than a quarter of a century to studying bees, who has published extensively in the peer-reviewed literature, who is trying to shed light on why bee colonies are dying, and who has tried to bring the pesticide industry and environmentalists to the same table.  You tell me why he’s being pilloried.