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)
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)
This would include mustards, clover and buckwheat, plants that honey bees love.
Kellison, the executive director of the Santa Rosa-based Partners for Sustainable Pollination, will speak Thursday, Aug. 8 at the 13th annual Sustainable Winegrowing Field Day, to be held at the Shone Farm at 7350 Steve Olson Lane, Forestville.
The field day is sponsored by the Sonoma County Winegrowers, Santa Rosa Junior College Agriculture/Natural Resources Department and the California Sustainable Winegrowing Alliance.
Kellison, to speak at 11:30 a.m., will cover bee-friendly farming, agricultural practices to improve bee health, and why it’s important to plant bee friendly landscapes, including bee gardens. "One major factor in the decline of all bees is the lack of food plants," she says.
Wine growers and beekeepers can work together to make better bee nutrition a reality, Kellison says.
Natural forage and nutrition are essential to good honey bee health and to their ability to cope with pests, pathogens and other stressors, she points out. "Special consideration must be given to encouraging plantings of late summer and fall blooming plants to help hives survive through the winter to the next blooming season."
Among the half-dozen speakers at the field day will be Doug Gubler of UC Davis, who will discuss “Fungicide Resistance Management and Prevention for Grapevine Diseases." Lucia Varela, UC Cooperative Extension pest advisor, will provide a display on how to identify the adult Virginia creeper leafhopper.
Partners for Sustainable Pollination (PSP), founded in 2007, aims to work with farmers and beekeepers to improve the health of honey bees and support native pollinators. "We foster awareness and support for providing increased availability of flowering plants to honey bees and native pollinators," Kellison says.
Partners include local conservation districts, growers, beekeeping and farm groups, and other stakeholders.
One of the PSP advisors is Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology.
Honey bee foraging on mustard, a good cover crop for bees. (Photo by Kathy Keatley Garvey)
Upside down honey bee on mustard. (Photo by Kathy Keatley Garvey)
You've probably seen a blue moon, which happens every two to three years. That's when a second full moon occurs in a single calendar month.
You've also probably seen blueprints, blue books and blue-plate specials. You've sung the blues and you've been blue.
But, have you ever seen a blue honey bee? As blue as...well...a blueberry?
We recently visited the half-acre Häagen-Dazs Honey Bee Haven on Bee Biology Road, University of California, Davis, when we saw a...drum roll...blue bee! It was foraging on a purple coneflower.
I captured the image with a Nikon D700 camera, equipped with a 105mm macro lens. Settings: shutter speed, 1/160 of a second; 6.3 f-stop; and 800 ISO. No flash. No tripod.
Honey bee guru/Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology looked at the photo and agreed it was a blue bee.
Now Mussen, who has been with the department since 1976 and is a favorite of the national news media, knows bees. He's also captured many images of bees, none blue (although many beekeepers have turned blue, especially during massive colony losses).
So, a blue bee?
"The exoskeletons of insects are waxy and oily," Mussen said. "Given just the right angle to the sun, you can see structural colors that are not the true pigments of the exoskeleton. In fact, there are some very shiny, metallic-looking insects that lose their sheen when they die, never to be seen again."
Just the right angle to the sun.
Once in a blue moon...
A blue honey bee on a coneflower. (Photo by Kathy Keatley Garvey)
Blue bee scaling the coneflower. (Photo by Kathy Keatley Garvey)
The California Gold Rush (1848-1855) has nothing on honey bees.
Sometimes foraging honey bees are covered with their own kind of gold--pollen--or protein for their colonies.
We saw this honey bee dusted with gold from head to thorax to abdomen as she gathered pollen from blanket flowers (Gaillardia). Her flight plan seemed uncertain, as her load was heavy and her visibility, poor. She struggled to take off, but take off she did.
Speaking of the Gold Rush and honey bees, entomologists always associate the arrival of honey bees in California with the California Gold Rush. That's because honey bees were introduced to California in 1853, right in the middle of the Gold Rush.
Back then, the hills were covered with wildflowers where bees gathered nectar (carbohydrates) and pollen (protein). Today, however, scientists are worried about bee malnutrition.
"Honey bee colonies need a mix of pollens every day to meet their nutritional needs," says Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology. "In fact, they should have a one-acre equivalent of blossoms available to them daily to meet their demands. They can fly up to four miles from the hive--a 50-square mile area--to gather that food and water (and propolis, plant resin)."
A worried beekeeper recently asked him about the declining bee population and wondered why his own colonies were dwindling. In addition to malnutrition, Mussen listed a few other possibilities:
Varroa mites – "They suck the blood from developing pupae and adult bees, shortening their lifespans. They vector virus diseases, the easiest to see being deformed wing virus. If you have adult bees around the colony with curly, undeveloped wings, then you have too many mites. If you see mites on the bees when you look in the hive, that is too many mites."
Nosema ceranae and other diseases – "You need a microscope to see the spores of a Nosema infection. Go to Randy Oliver’s webpage, Scientificbeekeeping.com, and look at the information on Nosema ceranae and spore counting."
Contact with toxic chemicals – "Since your bees can fly up to four miles away to forage, that also is the distance within which they can get into trouble with bee-toxic chemicals. It is not likely that the organic farm is a source. However, if there are other farms around, or if your neighbors (golf courses, shopping centers, parks, playgrounds, etc.) are having problems with sucking or chewing insects, they may have used one of the neonicotinoids on their shrubs or trees. Turf and ornamental dosages are considerably higher than those used in commercial agriculture. So, the amounts of toxins in nectar and pollens can be toxic to honey bees and other pollinators."
Mussen also acknowledged that California buckeye blossoms are toxic to bees. "This was a fairly dry spring," he said. "Not too many weeds and wildflowers were around when the California buckeye came into bloom. Buckeye pollen is toxic to developing bee brood and to adult bees, if it gets to be their primary food source in the colony."
The problem could also be due to other issues as well, Mussen said. "Maybe the queens did not mate with enough drones, or the queens got too hot or too cold during their journeys to your hives, etc."
"As beekeepers, it is up to you to stick your nose in the hive, look at everything and try to determine what may be going wrong. If you are feeling way too new at this to have any idea of what is going on, then contact your local bee club--there is one in practically half of the California counties--and find someone to help access your problems."
And the pollen, that precious protein? "When beekeepers examine their hives, they should see a good supply of pollen with many colors," Mussen says.
Honey bee is covered with pollen from a blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)
Honey bee is dusted with pollen from the blanket flower. (Photo by Kathy Keatley Garvey)
Lift off? The bee struggles to take off. (Photo by Kathy Keatley Garvey)