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Wild pollinators cannot replace honey bees . . .

At least not in the way we’d like. In the past few years a flood of articles has heralded native pollinators as “saviors”—groups of selfless, tireless, seldom-seen gladiators that are going to step in and save our food supply once the honey bees die off.

This is a comforting thought, and perhaps one day native pollinators will shoulder the bulk of our pollination needs—but it won’t happen within our current system of agriculture. It can’t. Successful transition to native pollinators will require nothing short of a complete overall of our current farming system.

If you read about the biology and ecology of wild pollinators, you will see they can be very efficient in terms of the number of flowers pollinated per minute. So efficient, in fact, that you wonder why the heck we ever started using honey bees. But as you dig deeper, you will also see they have very different life cycles and habitat requirements.

Some native pollinators will forage only a few hundred yards from their homes while honey bees will easily cover a three-mile radius—even more if resources are scarce. Some native pollinators visit only one plant species, or several, while honey bees pollinate hundreds. Some native pollinators are active only a few weeks of the year while a honey bee colony will forage any time the weather permits. Most native pollinators live singly or in small groups while honey bees live in massive colonies. The list goes on.

In the “old days,” let’s say before the end of WWII, people who kept honey bees kept them for honey. And if you didn’t keep bees, you didn’t worry about pollination. In fact, no one paid any attention to pollinators because there was no shortage. A farmer planted a field, the pollinators did their thing, and a crop was harvested. Short-lived, picky pollinators weren’t a problem because there were hundreds of different kinds. There was always one or a dozen other species to pick up where the last one left off.

But the Green Revolution changed how we farm and, before long, there weren’t enough native pollinators to do the job. The fields were too big, the habitat was too scarce, and pesticides were everywhere. As farms got bigger and more mechanized, honey bees had to be trucked in along with other forms of migrant labor.

Even the people who are currently studying native pollinators concede that without significant changes, native bees might supplement—but not supplant—honey bees. Some experts estimate that up to 30% of the farmland would have to be converted to bee habitat. Hedgerows, borders, and habitat strips would have to be interspersed with crops. This reserved land would need to remain un-tilled and be planted with large numbers of flowering plants so that something was always in bloom.

Thing is, even with all those resources devoted to wild species, it might not be enough. We would have to change pesticide practices, stop poisoning roadside weeds, and eliminate larger-than-life fields. We would have to become stewards—rather than pillagers—of the land.

I wouldn’t want to discourage anyone from keeping a hive of honey bees or tacking a bee block to a fencepost. But even thousands of them won’t assure a future food supply. To do that we must change the way we farm—from endless rows of monoculture to GMOs to weed control—it all has to be fixed. Native pollinators can’t save us unless we save them first. Care of pollinators needs to be job one.

Rusty
HoneyBeeSuite

Bumble bee on ceoanthus.
Bumble bee on ceoanthus.

Carrot honey . . . really!

Carrot honey is indeed unusual—unusual because domesticated carrots, Daucus carota, are a biennial crop that develop their famous taproots during the first summer of growth. When you want to grow a carrot, you buy a seed, plant it, harvest the carrot two or three months later, and never see a carrot flower. So how do you get carrot honey?

To get carrot honey you have to find a seed grower—a farmer who grows carrots for the express purpose of harvesting their seeds at the end of the plant’s second year of life. And what better place to find a seed farmer than in Oregon?

Oregon is famous for seed production. The Willamette Valley produces most of the grass seed grown in the United States, as well as seeds for many vegetables and herbs. Other parts of Oregon also grow seed, and the carrot honey I tasted came from Madras, an agricultural community in central Oregon. I’m told that carrot seed is not grown in the Willamette Valley because the crop tends to out-cross freely with wild carrot (Queen Anne’s Lace), a plant that is plentiful in that local area.

Although carrots are readily pollinated by wild insects including bees, wasps, and various flies, vast acreages of carrot flowers need the help of honey bees or mason bees to get a reliable seed set. The bonus for the beekeeper is a crop of rare honey.

Carrot honey has a dark amber color with an aroma reminiscent of chocolate. The taste is strong with a bite to it—a sharp spike in an otherwise earthy, caramel flavor. I also detected a “grassy” aftertaste, not quite like foraging on a meadow, but something close to that. This honey would be intriguing in any recipe where you want the taste of the honey to shine through. It would also complement a balsamic vinegar and olive oil dressing. But even if you prefer your honey straight up, don’t miss this one; it is a different experience and a must-try for your life list.

Since I was tasting while writing, I’m now seriously stuck to the keyboard—a sweet occupational hazard. While I clean up this mess you should consider giving carrot honey a try. My sample came from Flying Bee Ranch in Salem, Oregon.

Rusty
HoneyBeeSuite.com

The wild carrot is closely related to the cultivated one. Photo by Vera Buhl.
The wild carrot is closely related to the cultivated one. Photo by Vera Buhl.

Wednesday wordphile: floral fidelity

Although honey bees are polylectic, which means they visit many different species of flowering plants, they also exhibit floral fidelity, which means that a bee visits only one kind of flower on any given foraging trip. If there are enough flowers of one type available, a honey bee will continue to visit that same kind of flower all day long.

Floral fidelity is one of the main reasons that honey bees are such great pollinators of agricultural crops. When released into an apple orchard, for example, the honey bees will just keep working the apples; they will pay little attention to the weeds flowering at the side of the field or growing between the rows.

Most native bees—while superb pollinators in their own right—will forage on anything they come across, whether it be apples, dandelions, or thistles. However, native bees tend to visit more flowers per minute than honey bees, which partially makes up for being pollen packrats.

These two different foraging patterns go hand-in-hand with different flight ranges. Honey bees can fly for extremely long distances—a trait that allows them to keep searching for that same flower type and, consequently, allows them to pollinate huge tracts of monocropped farmland. Native bees fly only very short distances, so they are compelled to forage on anything they find within their range. (You can think of honey bees as obsessive/compulsive and native bees as pragmatic.)

From the beekeeper’s perspective, floral fidelity allows for the production of varietal honeys. If the honey bees were foraging randomly, it would be much more difficult to harvest a recognizable varietal.

The downside to floral fidelity to the honey bees is this: if the crop they are working has low-quality pollen, most of the pollen coming into the hive during the flowering period of that crop will have the same low-quality. Or if the crop has been treated with a systemic pesticide that resides in pollen, the honey bees will get an extra high dose of the pesticide.

Native bees who mix up their pollen sources as they forage have a better chance of bringing home a “balanced diet”—and one that may not be so heavily loaded with pesticides.

Floral fidelity is also called floral consistency, flower fidelity, and other similar names.

Pollen can carry disease to native bees

While studying pesticides in pollen, I was always curious about the potential for pollen to carry disease organisms as well. Indeed, a new study that appeared in the December 22 PLoS ONE confirmed my worst fears—that pollen may be a major route of viral infection from managed honey bees to wild native bees.

The authors of the study examined the four viruses that are most commonly found in North American honey bees—deformed-wing virus, sacbrood virus, black queen cell virus, and Kashmir bee virus—plus Israeli acute paralysis virus, which is often found in conjunction with colony collapse disorder. They asked a number of questions about bee-to-bee disease transmission and then set up a series of experiments to answer those questions.

They found eleven species of wild pollinators in Pennsylvania, New York, and Illinois that carried at least some of the viruses. These viruses were much more likely to show up in wild pollinators that lived near apiaries known to be infected with the various pathogens.

Tests on both the pollen and the bees themselves showed that in many cases disease-free foragers were carrying pollen loads that contained viral diseases—especially deformed-wing virus and sacbrood virus. This finding indicates that the pollen, itself, may be capable of transmitting the disease from one bee to another—it may not be necessary for an infected bee to pass the virus directly to another bee. Similar to human viruses that survive on door knobs, these bee viruses appear to survive on pollen grains.

In other experiments, honey bees and bumble bees kept in greenhouses were shown to transmit Israeli acute paralysis virus among themselves by simply foraging on the same flowers. The disease moved freely in both directions, from honey bees to bumble bees and from bumble bees to honey bees.

The authors point out that the exact mechanisms of disease transmission via flowers and pollen are not understood and more study is needed to see if host plants have a greater role in disease transmission than just as physical carriers. In the meantime, it is important for beekeepers to understand the impact diseased honey bees may have on wild pollinator populations. Honey bee health needs to be a priority if we are to maintain the health—or perhaps the very existence—of wild pollinator populations.

For more information, you can download the complete paper for free at http://www.plosone.org/article/info:doi/10.1371/journal.pone.0014357.

Rusty

Pollinators are not going to change, so we have to

It is easy to blame the loss of bee habitat on “them”—them being industrial farms, expansive orchards, sprayed fields, and freeways kept neat with herbicides. But in truth, our modern cities and suburbs are just as bad. We have covered the land with mulch, decking, concrete, flagstones, bricks, pavement, and lawns. None of these things are attractive to bees—not managed bees and certainly not solitary bees.

We install many of these unnatural surfaces to suppress weeds and mud. But it’s weeds and mud that the bees need. Most of the world’s bee species are solitary, and most of the solitary bees either nest in the ground or use mud to build their homes. By covering every square inch of earth with something to protect us from mud, we deny these creatures a place to live.

To make it all worse, the things we plant are not helpful to bees either. Lawns are carefully tended to preclude any broad-leaved plants. Lawns used to be planted with a clover and grass mix. Those lawns never needed nitrogen fertilizer because the bacteria that live on the roots of clover fixed atmospheric nitrogen into something the grass could use. But clover has long since fallen out of fashion. Now we kill the clover with chemicals and then add chemical fertilizer to make up for the lack of nitrogen. How can we be so confused?

And instead of lining our lawns with flower borders, we now use evergreen trees and shrubs that are easy care and don’t flower. Collectively, our lawns look sterile and uninviting—like the front of a bank. Sure, they are neat and trim, but nothing lives there.

Part of the problem is that we are busy, so we want landscapes that are easy to care for. But our gains in ease have been more than offset by losses in beauty, biodiversity, and seasonality. Our lawns look the same regardless of whether it is spring or fall, summer or winter. And somehow it is not okay to have worn and dead plants falling to the ground or dry seedheads releasing—heaven forbid—seeds. Everything must be clean, neat, sterile, and artificial. It is more acceptable to have a pink plastic flamingo in your suburban yard than a cosmos that has turned brown and fallen over. A junk car in the driveway is more acceptable than an overgrown lawn. And you can spread all the poisons you want—but please get rid of those dandelions!

We won’t be able to solve the problem of diminishing pollinators until we redefine what is good and bad in urban and suburban landscapes. We need to convert at least a portion of our close-cropped, weed-and-feeded, monocropped lawns into patches of meadow, wild flowers, clovers, and native plants. We have to understand that it’s okay for a plant to die back in the winter and for seeds to blow on the wind. And there has been room for—dare I say it?—mud .

Each time I ponder what I can do for the bees I realize that the problem is bigger than it first appears. Laws, ordinances, and homeowner associations preclude a lot of things that would be good for pollinators. Social norms preclude a lot more. And when pressed, people will explain that pollinators live “out there”—in the country, in the woods, or in the wild.

But there is no “wild” anymore, and the very worst place for bees is the agricultural regions. And the woods? The Department of Natural Resources in my own state routinely sprays new plantings of Douglas-fir with herbicide—which leaves nothing for wild bees to eat.

Unfortunately I don’t have an answer for any of this, but something has to give. Values have to change. A whole lot of people have to care. Until that time, the plight of the pollinators is simply going to get worse—and most of us won’t even know it is happening.

Rusty