Eric Mussen

That's the question PBS Newshour asked Extension apiculturist (retired) Eric Mussen of the UC Davis Department of Entomology and Nematology for its "Just Ask" feature.  

Mussen, who retired in June after 38 years of service but continues to maintain an office in Briggs Hall on the UC Davis campus, has been stung plenty of times. And the whole world knew it when this photo of "The Sting" (below) went viral.

When a bee stings, it cannot remove its barbed stinger without yanking out its abdominal tissue, aka "guts." It's basically a suicide mission in defense of its hive. Of the three castes in the colony, only the female worker bee dies when it stings. The queen can sting multiple times. The drone (male) has no stinger.

The stinger is hollow and pointed, like a hypodermic needle, Mussen told PBS Newshour reporter Anna Christiansen. The stinger, he explained, contains two rows of lancets, or saw-toothed blades. 

Christianson also quoted Mark Winston, biologist and author of Bee Time: Lessons from the Hive (Harvard University Press) as saying that the blades alternate, “scissoring together into your flesh."

"It looks — and works — like a screw anchor, meaning that once in, the stinger can't retract," Christianson wrote. "Muscles connect the stinger to a venom sac, from which a cell-destroying toxin is pumped into the hole."

Mussen further explains bee stings in a UC Statewide Integrated Pest Management (UC IPM) Pest Note, Bee and Wasp Stings.

"Stingers are effective weapons because they deliver a venom that causes pain when injected into the skin," Mussen wrote. "The major chemical responsible for this is melittin; it stimulates the nerve endings of pain receptors in the skin. The result is a very uncomfortable sensation, which begins as a sharp pain that lasts a few minutes and then becomes a dull ache. Even up to a few days later, the tissue may still be sensitive to the touch."

"The body responds to stings by liberating fluid from the blood to flush venom components from the area. This causes redness and swelling at the sting site. If this isn't the first time the person has been stung by that species of insect, it is likely that the immune system will recognize the venom and enhance the disposal procedure. This can lead to very large swelling around the sting site or in a whole portion of the body. The area is quite likely to itch. Oral and topical antihistamines should help prevent or reduce the itching and swelling. Try not to rub or scratch the sting site, because microbes from the surface of the skin could be introduced into the wound, resulting in an infection."

Mussen says that nearly everyone has been stung by an insect at one time or another., and for beekeepers, it comes with the occupation.  "It's an unpleasant experience that people hope not to repeat, but for most people the damage inflicted is only temporary pain," Mussen wrote. "Only a very limited portion of the population—one to two people out of 1,000—is allergic or hypersensitive to bee or wasp stings. Although this publication is about stings from bees and wasps, the information pertains to stings from fire ants as well."

He warns that it is important to remove the stinger immediately because the venom will continue to pump for 45 to 60 seconds following a sting.  Mussen usually scrapes and removes the stinger with a fingernail. "Much has been written about the proper way to remove a bee stinger, but new information indicates it doesn't matter how you get it out as long as it is removed as soon as possible. Fingernails or the edge of a credit card are both effective tools. If a stinger is removed within 15 seconds of the sting, the severity of the sting is reduced."

Read more about bee stings in the PBS Newshour feature question, and in the UC IPM Pest Note, Bee and Wasp Stings.

Give me an "A" (for excellence).

Give me a "B" (for bee).

Give me a "C" (for Cosmos).

Watching honey bees collect nectar and pollen on the showy Cosmos (Cosmos bipannatus) is not to be missed.

As if performing a ballet, the enchanting bees enter stage left and are such show-stoppers that you want to erupt with applause at every precise move. Bravo!

Cosmos is a spectacular annual with saucer-shaped floral heads, ranging in color from white and pink to lavender and crimson. It's a relatively late bloomer. In our family bee garden, they began blooming in late summer and are continuing into fall.

In their newly published book, California Bees and Blooms: A Guide for Gardeners and Naturalists, entomologists Gordon Frankie of UC Berkeley and Robbin Thorp of UC Davis teamed with photographer Rollin Coville (UC Berkeley-trained entomologist) and botanist Barbara Ertter (UC Berkeley) to offer interesting information on bee species and advice for growing and managing bee friendly plants. It's a "must-have" for every gardener and naturalist or would-be gardeners and naturalists. Did you know there are more than 1600 different species of bees in California alone, and some 4000 throughout the country?

One section goes into depth about plants, including Cosmos. You'll learn its description, origin and natural habitat, range and use in urban California, flowering season, resource for bees (nectar and pollen), most frequent bee visitors, and bee ecology and behavior. It's not surprising that the book, by Heyday, is published in collaboration with the California Native Plant Society.

And what are the most frequent bee visitors? "A wide variety of bee species, especially Melissodes robustior, Melissodes species, and Halictus ligatus. In the Central Valley, it attracts honey bees, Agapostemon texanus, Anthophora urbana, Xeromelecta californica, and Svastra obiqua expurgata."

The authors describe all those species--and more. Some we know generally as longhorned bees, sweat bees, metallic green sweat bees, digger bees, and sunflower bees.

Blooms. Bees. Beautiful.

Hide the cactus! There's a Mexican cactus fly in our midst.

A large black fly hovers over a Mexican sunflower (Tithonia) in our bee garden and then drops down to sip some nectar. At first glance it looks like a carpenter bee but this one hovers like a syrphid fly, aka flower fly or hover fly.

"Hover fly," I say.

Entomologists Martin Hauser, Lynn Kimsey and Robbin Thorp quickly identified the critter.

Hauser, senior insect biosystematist with the Plant Pest Diagnostics Branch of the California Department of Food and Agriculture, says it's in the genus Copestylum (with over 350 species in the new world) and figured it to be the species,  mexicanum, commonly known as the Mexican cactus fly.

Said Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis: "Nice, this is actually a kind of syrphid flower fly, better known as a cactus fly. The larvae breed in rotting cactus tissue."

Native pollinator specialist Robbin Thorp, emeritus professor of entomology, also figured it to be a Mexican cactus fly, Copestylum mexicanum.  "It's commonly known as a cactus fly (Syrphidae, Tribe Volucellini).  "It used to be in the genus Volucella, But now it's in the genus Copestylum."

This fly is not small. It's about 3/4 of an inch long. It lays its eggs in rotting plant material "and they really like rotting cacti," Hauser commented. "As far as I know, they only go into dying cacti and do not attack healthy cacti…. But there is actually not much known about their biology."

The resident cacti expert at our house is worried, showing his best prickly pear expression. He quickly canvasses the yard. Whew! No rotting cacti. All thriving and in good health.

So far, so good...

Jeweled beetles at the Bohart. (Photo by Kathy Keatley Garvey)

That's the theme of San Francisco's Exploratorium Pier 15 event on Thursday night, Oct. 2.

Graduate student Ralph Washington of the UC Davis Department of Entomology and Nematology, will be staffing the Bohart Museum of Entomology table for four hours at the event.

Washington, who studies with major professor Steve Nadler and is a Bohart Museum associate, will showcase the “oh my” drawers, so named because onlookers exclaim “oh my” when they see them; and live animals from the petting zoo,  which include Madagascar hissing cockroaches and  walking sticks. He also will provide a slide show presentation focusing on camouflage and deception in the insect world. 

The event will take place from 6 to 10 p.m., at Pier 15, located at Embarcadero at Green Street, San Francisco. General admission is $15; for members, it is $10. The event is open only to adults 18 and over.

“After Dark” is a mixture of theater,  cabaret and a gallery, according to its website.

Tabatha Yang, education and outreach coordinator at the Bohart Museum, said "After Dark" is aimed at young adults.

From the website: 

“Delve into the science behind deception at After Dark. Find out how expert wine detective Maureen Downey exposes costly counterfeits—without uncorking a bottle. Glimpse the blurred margins between science and art in Victorian spirit photography with Fine Arts Museums of San Francisco curator Melissa Buron, and walk through a virtual mirror staged by Exploratorium physicist Paul Doherty. Play with exhibits exploring the nature of perception, including a room-sized “Vanishing Act.” Encounter the uncanny in the mischievous mentalism of Brad Barton, Reality Thief, and let magician and Exploratorium scientist Luigi Anzivino show you how the odds can be stacked against you in a seemingly innocent game of chance. Learn the tricks carnivorous plants use to lure their treats, meet servals and ocelots from Bonnie Cromwell's Classroom Safari, and become a connoisseur of camouflage—animal and otherwise.”

Information on tickets and parking and other data on the Exploratorium Pier 15 website.