Posts Tagged: Eric Mussen
It won't bloom until summer, but already many eyes are on the California buckeye.
The tree's blossoms are poisonous to honey bees. Bees are attracted to them and forage on them, but the end result of the food provisions to the colony can be deformed larval development.
We've seen bee hives within a quarter of a mile of California buckeyes (Aesculus californica). And we've seen honey bees, native bees and other pollinators foraging on the blossoms.
At the recent UC Davis Pollinator Gardening Workshop hosted by the California Center for Urban Horticulture, Extension apiculturist Eric Mussen talked about the poisonous plants. (See PowerPoint presentations.) That led to one workshop participant wondering if the flowers of the California buckeye are poisonous to native bees. (Honey bees are not native; the European colonists brought them to the Jamestown colony, Virginia, in 1622).
Responded Mussen: "My guess: either the native bees that have been in the areas around California buckeye for a long, long time are not poisoned by the pollen or they have been selected (by death of the other genetic types) to avoid the pollen, that eons of natural selection have adapted them to coexist with California buckeye while using their resources."
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, shared: "We know California buckeye nectar and/or pollen is toxic to honey bees from years of experience with managed hives. Toxicity to native bees and other flower visitors is not so easily determined and to my knowledge has not been investigated. The fact that populations of native bees and butterflies visit California buckeye flowers and continue to persist in areas where the tree is a dominant part of the plant community tends to confirm what Extension apiculturist Eric Mussen says about them. Some good research projects here. So we still do not know if it is the nectar, pollen, or both that may be toxic to honey bees, much less to native flower visitors."
According to gardeningguides.com, the seeds in their raw state are poisonous to humans, but native Americans learned to get around that and use them for food. They pounded the seeds into flour and then cooked the mixture. "This tree had multiple cultural uses among California Indian tribes," the website says. "Many indigenous groups utilized buckeye seeds for food, often when other plant food sources were scarce. These tribes included the Costanoan, Salinan, Kitanemuk, Serrano, Wappo, Sierra Miwok, Coast Miwok, Chumash, Kawaiisu, Northern Maidu among others. The Pomo ate the seeds even when other important food plants were plentiful. The seeds are poisonous to humans in the raw state. Thus, the nuts were cracked open with a rock, the shells removed, the seeds pounded into flour, and their toxic saponins removed in a lengthy leaching process. The meal was subsequently cooked and eaten. There are many different methods for processing and cooking buckeye seeds for food, depending upon the tribe. The seeds have medicinal properties and were cut into pieces, mixed with water, and made into suppositories for hemorrhoids by the Costanoan and Kawaiisu. The Pomo cut bark from the base of the tree and made a poultice, which was laid on a snakebite. Young buckeye shoots were sometimes used as spindles or twirling sticks in fire-making kits of the Sierra Miwok, Northern Maidu, Wappo, Yahi and other tribes. Many tribes mashed buckeye nuts and poured the contents into quiet pools to stupefy or kill fish."
And, no wildlife will eat buckeye seeds except squirrels, such as the California ground squirrel (Citellus beecheyi).
Meanwhile, the poisonous blossoms continue to beckon the honey bees--and their colonies keep producing deformed bees.
Honey bee foraging last May on a California buckeye, which is poisonous to honey bees. (Photo by Kathy Keatley Garvey)
A California buckeye blooming in May of last year on the UC Davis campus. (Photo by Kathy Keatley Garvey)
Indeed, to the untrained eye, the drone fly (Eristalis tenax) appears to be a bee. It's not; it's a fly.
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, calls the drone fly "The H Bee." That's because there's an "H" on its abdomen (see photo). Like all flies, however, it can be distinguished by one pair of wings and stubby antennae. The larva of the fly is a rat-tailed maggot that lives in drainage ditches, pooled manure piles and other polluted water. The adults are floral visitors. Pollinators.
The "H Bee" was among the pollinators that Thorp discussed at the UC Davis Pollinator Gardening Workshop, hosted March 6 by the California Center for Urban Horticulture.
Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology, switched from bee mimics (drone flies, syrphid flies and other insects) to talk about the "real" honey bees, Apis mellifera, which European colonists introduced to what is now the United States in 1622. "The honey bees' biggest problem today is malnourishment," he said. "A single honey bee colony requires an acre of bloom to meet its nutritional needs each day," he said.
The queen can lay 2000 eggs a day in peak season. "One cell of honey and one cell of pollen make one bee."
He urged the participants to "try to plant for late summer and fall bloom, when honey bees in California are having a hard time finding nectar and pollen resources."
Mussen cautioned that bees are subjected to toxic pollens and unnatural toxins (pesticides). Plants poisonous to bees include the California buckeye (Aesculus californica) death camas (Toxicoscordion venenosum), corn lily (Veratrum californicum) and some locoweeeds (Astragalus spp.)
Pesticides inside the hive (used to control varroa mites) and outside the hives can be fatal. However, he said, "any kind of pesticide a bee encounters--there's always a physiological change."
Following the morning-long speaker presentations, the participants visited the UC Davis Arboretum Teaching Nursery on Garrod Drive to check out and/or purchase Arboretum All-Stars and other plants, and they toured the Häagen-Dazs Honey Bee Haven, a half-acre bee friendly garden on Bee Biology Road that is under the wing of the UC Davis Department of Entomology and Nematology. The garden is located next to the Harry H. Laidlaw Jr. Honey Bee Research Facility.
Among those traveling the longest distance were Lake Tahoe UC Master Gardeners Lynne Broche and Bonnie Turnbull and Turnbull's 14-year-old daughter, Jessie Brown, a junior Master Gardener and an avid insect photographer.
The ceanothus blooming in the haven especially drew the attention of the workshop participants. Insects foraging in the ceanothus included two so-called "H bees"--the honey bee and its impostor, the H-marked drone fly.
The drone fly, Eristalis tenax, is often mistaken for a bee. The fly has the letter "H" on its thorax. (Photo by Kathy Keatley Garvey)
essie Brown, 14, a junior UC Master Gardener with the Lake Tahoe Master Gardeners, photographs insects in the ceanothus at the Häagen-Dazs Honey Bee Haven. (Photo by Kathy Keatley Garvey)
A honey bee apparently stung a 47-year-old father on his foot and he went into anaphylactic shock. Rushed to the hospital, he died 10 days later when his kidneys and heart failed. The article reported he was 6 feet, five inches tall, and weighed 17 stones, which is 238 pounds. (One stone equals 14 pounds).
His family indicated he was unaware of his allergic reaction to bee stings.
A sad and tragic case, indeed.
We know of people who have suffered severe allergic reactions and were raced to the hospital in time and fortunately survived. One was a Northern California parks employee who did not know he was allergic to bee stings.
How many people in the United States are allergic to honey bee stings? Approximately one or two out of every 1000 people, says Extension Apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology. "The severity of the response, to even a single sting, varies considerably from person to person."
Immediate injections with epinephrine will usually delay the possibility someone unable to breathe. Then a quick trip to a hospital where medical personnel can administrate antihistamines, steroids "and likely more epinephrine" are in order.
"While honey bees away from their hives normally do not pose too much of a sting threat, if the bees are intoxicated by exposure to certain pesticides, they can become an abnormal sting threat at distances quite a ways from the hives. Additionally, individuals who fear a sting, with good reason, sometimes are more apt to try to shoo the bee away. If a bee already is close to stinging, the additional movement of the 'shooer,' or if there is contact with the bee, results in a much greater likelihood of a sting."
Another piece of good advice that Mussen offers: "Individuals who do not appreciate attention by bees should do everything they can to not smell good to a bee. The use of flower-scented or bee products-scented soaps, shampoos, perfumes, or colognes should be avoided. There is no documented scientific study that suggests that honey bees can detect the odor of fear in humans. But if we watch from a distance, the physical reactions of fearful people often tend to be more likely to cause stings than the behavior of the rest of us."
Photographers who capture images of worker bees foraging in flowers are often asked if they've ever been stung. After all, they're just inches away from them. The usual answer: No. The bees are too busy gathering nectar and pollen for their colonies. Stings can and do occur when the worker bees are defending their hives. Or when you accidentally step on one.
Read Mussen's information on bee and wasp stings on the UC Integrated Pest Management (UC IPM) website.
This honey bee, in the process of defending her hive, is stinging Extension apiculturist Eric Mussen of UC Davis. That's her abdominal tissue being pulled out. (Photo by Kathy Keatley Garvey)
Close-up of two stings. (Photo by Kathy Keatley Garvey)
"Go native" with native bees, that is.
A bee condo is a block of wood drilled with specially sized holes for nesting sites. Bees lay their eggs, provision the nests, and then plug the holes. Months later, the offspring will emerge.
In our backyard, we provide bee condos for BOBs (short for blue orchard bee) and leafcutter bees.
In the summer it's fun watching the leafcutter bees snip leaves from our shrubbery and carry them back to their bee condo. It's easy to tell the nesting sites apart: BOB holes are larger and plugged with mud, while the leafcutter bee holes are smaller and plugged with leaves.
Osmia lignaria, a native species of North America, is sold commercially for use in orchard crop pollination.
If you want to learn how to build them or where to buy them, Thorp has kindly provided a list of native bee nesting site resources on the Harry H. Laidlaw Jr. Honey Bee Research Facility website. You can also purchase them at many beekeeping supply stores. (Also check out the Xerces Society's website information.)
Better yet, if you'd like to learn more about native bees and their needs, be sure to register online for the Pollinator Gardening Workshop on Saturday, March 15 on the UC Davis campus. Hosted by the California Center for Urban Horticulture, it begins at 7:30 a.m. in Room 1001 of Giedt Hall and ends at 2 p.m. with a plant sale at the UC Davis Arboretum Teaching Nursery and a tour of the Häagen-Dazs Honey Bee Haven, a half-acre bee friendly garden on Bee Biology Road, west of the central campus. For the small fee of $40 you'll receive a continental breakfast and box lunch and return home with an unbee-lievable wealth of knowledge. Speakers will include several honey bee and native bee experts: native pollinator specialist Robbin Thorp; pollination ecologist Neal Williams and Extension apiculturist Eric Mussen. See the complete list on the website.
You'll be hearing from Robbin, Neal and Eric, but you'll be thinking about BOB.
Leafcutting bees heading home to their condo. (Photo by Kathy Keatley Garvey)
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, shows Danielle Wishon of the California Department of Food and Agriculture a bee condo. (Photo by Kathy Keatley Garvey)
Blue orchard bees on display at the Bohart Museum of Entomology. (Photo by Kathy Keatley Garvey)
Close-up of bee nesting sites shown March 2 at the Bohart Museum of Entomology. (Photo by Kathy Keatley Garvey)
When a honey bee stings you, she makes the supreme sacrifice and dies. She's usually defending her colony. In the process, she leaves behind part of her abdomen. A beekeeper simply scrapes the sting with a fingernail or a hive tool to stop the pulsating venom and continues working.
But is it ever possible for a bee to "unscrew the sting?"
A beginning beekeeper asked Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology, that very question last week.
She prefaced her question this way: "Richard Dawkins wrote in his biography that he observed a bee working her stinger out of his hand--unscrewing, so to speak--thereby not losing her stinger or her life. Is this true? I'm just a beginning beekeeper but have read many books on the subject and have never come across this interesting bit of information."
Mussen has been asked thousands of questions about bees since he joined the UC Davis faculty in 1976. Bee stings are just one of the topics. Like all beekeepers, he's been stung many times. It's no big deal. However, one documented bee sting (below) turned out to be rather a big deal. It went viral. (It went from winning a feature photo contest sponsored by the Association for Communication Excellence (ACE), an international association of communicators, educators and information technologists, to being named the Huffington Post's "Most Amazing Photos of 2012"; one of the Sacramento Bee's top 10 news stories of 2012; and My Science Academy's top photos of the year. Along the way, scores of websites named it "Picture of the Day." It also will appear in a number of books.)
The photo (taken by yours truly) shows Mussen being stung by a bee in the apiary of the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road, UC Davis. At the time, we were walking through the apiary when he noticed a bee loudly buzzing around him. "Get your camera ready, Kathy," he said. "The bee's going to sting me."
That's exactly what the bee did. If you look closely, you can see the abdominal tissue, aka "guts," as she's trying to pull away. Usually a bee sting is a clean break.
So, can a bee "unscrew the sting?"
"As you may know, the sting of an adult worker honey bee has backward-pointing barbs that tend to hold the bee sting in the victim's flesh," Mussen told the beekeeper. "However, how well the sting stays stuck depends upon how deeply it was pushed in. Yes, some bees seem to make only a half-hearted effort to sting. The point of the sting pierces the skin, but doesn't go in very deeply. At that point, the sting can be pulled out if the bee begins to leave. It goes back up, inside the bee, but I do not know if, or how much, damage was done to the bee."
"These half-hearted stings are more commonly encountered with quite young workers. Sometimes the sting remains, but no venom is felt. Sometimes, a slight tinge of venom is momentarily noticed, then it is gone. So, while most stings are the full-blown, driven-pretty-deep-into-the-flesh type, there are less assertive attempts that result in intermediate sting results. The sting cannot be 'unscrewed,' because the barbs on the sting are directly across from each other and not in a spiral. However, the barbs are larger as the sting penetrates deeper."/span>
Extension apiculturist Eric Mussen getting stung on the wrist. (Photo by Kathy Keatley Garvey)