Honey bees, yes! Bumble bees, yes! Carpenter bees, uhh, not so much.
Ever seen carpenter bees drilling holes in dead limbs or untreated fence posts to build their nests? No? Well, you've probably seen them in their "robber role," piercing a hole in the corolla of a flower and robbing the nectar, bypassing pollination.
"Beneficial insects or pests?" we asked native pollinator specialist Robbin Thorp, distinguished emeritus of entomology at the University of California, Davis.
"Carpenter bees are controversial and their status as pests or beneficial insects is complicated," Thorp noted. "Some people consider only the negative effects of carpenter bee behaviors--tunneling in wood structures we create or nectar-robbing from some long-tubed flowers--deeming them pests and seeking ways to control them.
"But carpenter bees are important pollinators in native plant communities, and even beneficial as pollinators of some crop plants such as passion fruit, blueberries, melons, hybrid cotton and they are effective buzz pollinators of tomatoes and egg plant," he said. "Even effects of their nectar robbing are not entirely negative. They may actually enhance out-crossing by forcing legitimate pollinators to visit more flowers thus increasing out-crossing. In some cases, they may actually pollinate flowers while nectar-robbing from them."
"Carpenter bee tunneling into wood is an initial step in breaking down dead limbs and logs as part of the recycling process in natural communities. It is when they burrow into untreated wood used in our constructions that they are considered pests."
Thorp said that "any damage caused by them should be weighed against their positive contributions in trying to determine whether to attempt to control them or not."
Bottom line: we consider carpenter bees beneficial.
California has three species of carpenter bees.
- The biggest is the Valley carpenter bee, Xylocopa varipuncta. It's about an inch long. The female is solid black, while the male, commonly known as "the teddy bear bee," is a green-eyed blond. Why teddy bear? It's fuzzy and does not sting--or as Thorp says "Boy bees don't sting."
- The second largest is the California carpenter bee or Western carpenter bee, Xylocopa californica, often found in the mountain foothill areas of northern and southern California. It's known for its distinctive distinctive bluish metallic reflections on the body, Thorp says. The females have dark smoky brown wings.
- The smallest is the foothill or mountain carpenter bee, Xylocopa tabaniformis orpifex. The females are black with light smoky-colored wings. The male has bright yellow marks on the lower part of its face and some yellow hairs on the top front of its thorax.
Check out the images and descriptions of carpenter bees on BugGuide.net).
Want to hear more about California's bees, which total some 1600 species? Thorp will be giving a two-hour presentation, "Bee Aware Bee Cause," on Saturday, Jan. 7 starting at 1:30 at the Rush Ranch Nature Center, 3521 Grizzly Island Road, Suisun. The site is located off Highway 12, two miles south of Suisun City. The event, free and open to the public, is sponsored by the Rush Ranch Educational Council, in partnership with Solano Land Trust, owner of Rush Ranch.
Thorp, who holds a doctorate in entomology from UC Berkeley, taught entomology at UC Davis from 1964 to 1994. Although emeritus since 1994, he continues his research, writings, bee identification, public outreach and other "bee-involved" activities from his headquarters in the Harry H. Laidlaw Jr. Honey Bee Research Facility at UC Davis.
Thorp co-authored the UC California book, California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday) and Bumble Bees of North America: An Identification Guide (Princeton University Press). He annually teaches at The Bee Course (American Museum of Natural History), at the Southwestern Research Station, Portal, Ariz. The two-week course is offered for conservation biologists, pollination ecologists and other biologists who want to gain greater knowledge of the systematics and biology of bees.
Doom or gloom? Boom or bloom?
Today is Earth Day, and millions of folks around the world stopped--at least for a moment--to pay tribute to the 46th annual observance. They planted trees, weeded their gardens, greeted pollinators, or just thought about environmental issues.
Every Earth Day, we pay special attention to the tower of jewels (Echium wildpretii). The biannual, native to the Canary Islands, off the coast of Morocco, is a favorite in pollinator gardens, including ours. Seven feet tall and graced with pinkish blossoms splashed with blue pollen, it lives up to its name...tower of jewels.
Then it morphs into a tower of bees. Hello, honey bees, bumble bees, sweat bees and carpenter bees.
As they dive in, will they not only survive but thrive? If we each do our part, we can help the pollinators thrive.
Happy Earth Day!
It's the easy way to do it.
A carpenter bee heads for a foxglove blossom and drills a hole in the corolla to sip the nectar. This is "nectar robbing"--bypassing the pollination process and heading straight for the reward, the nectar.
Honey bees are quick learners. Soon they're sipping nectar from the hole pierced by the carpenter bee and they are not supplying "pollination services," either.
The carpenter bees (Xylocopa tabaniformis orpifex) of the Central Valley have emerged and are creating their own little Lovers' Lane on the salvia.
More males than females. More buzzing than foraging. More chasing than capturing.
This is the "bug" that some folks are afraid of--they describe them as "big black bees heading right at me and scarin' the livin' daylights of me--close enough for a buzz cut."
Well, the males ARE quite territorial. But only the females are solid black. The males have yellow on their thorax and head.
But hey, they shouldn't scare the livin' daylights out of you. They're pollinators.
It's good to know your floral visitors. Not all floral visitors are honey bees. Some are carpenter bees, bumble bees, wool carder bees, longhorned bees, and leafcutting bees, to name a few. Some are syrphid flies that mimic bees and wasps.
If you're yearning to learn more about pollinators, then the all-day Pollinator Gardening workshop on Saturday, April 28 in Room 1001 of Giedt Hall, UC Davis, is for you. "Your Sustainable Backyard: Pollinator Gardening" is sponsored by the California Center for Urban Horticulture (CCUH) at UC Davis. Among the speakers: native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, who will discuss "Bees 101: Species Diversity and Behavior." Yes, that will include carpenter bees.
Thorp's knowledge of all things bees is totally amazing. You'll come away wanting to spread the word: carpenter bees are pollinators, too. Don't fear them.
Pollination ecologist Neal Williams, assistant professor of entomology at UC Davis, will share the "Importance of Pollinators and Conservation." Ellen Zagory, director of horticulture at the UC Davis Arboretum, will cover "Bee Plants." Vicki Wojcik, associate program manager of Pollinator Partnership, will speak on "Pollinator Gardening: Design and Maintenance."
You'll "learn about bees and what they do, and how gardeners can support healthy populations through simple gardening practices," said coordinator Melissa "Missy" Gable, horticulturist and program director of CCUH. "This workshop is intended for anyone with a love of gardening."
"We have entomologists, horticulturists and design experts presenting at Pollinator Gardening," Gable said. "This workshop is designed both to inspire gardeners and equip them with all the necessary tools to provision pollinating insects in their own landscape. Without the pollination services of European honey bees and native bees, what fruits and vegetables would be accessible to us? Come learn what you can do your part to support healthy bee communities." Check out the registration site.
Following the workshop, participants can visit (1) the Häagen-Dazs Honey Bee Haven, a half-acre bee friendly garden next to the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road and (2) the UC Davis Arboretum Teaching Nursery on Garrod Drive and perhaps buy a plant or two. The haven is open all year around from dawn to dusk (free admission) while the teaching nursery will be open that afternoon to registered participants for a look-see at the demonstration gardens and for plant sales.
Perhaps, just perhaps, you might want to buy salvia to attract such floral visitors as carpenter bees!
“I’ve got black bumblebees buzzing around our backyard like crazy,” the caller said. “They’re loud. Very loud. They’re dive-bombing and scaring the cat and dog. I’ve never seen anything like this before.”
The unwelcome visitors were not bumblebees. They were carpenter bees.
Carpenter bees? No, they don’t know how to read blueprints or frame floors and walls. They nest in weathered wood, like your fence posts, utility poles or firewood. They tunnel into your deck, railing, shingles and shutters.
They are pests. But they’re also pollinators.
Native pollinator specialist Robbin Thorp, professor emeritus at the UC Davis Department of Entomology, fields many calls about carpenter bees.
This one pictured below is a male carpenter bee, Xylocopa tabaniformis orpifex Smith NB, Thorp says.
“It is stealing nectar from the base of the flower. They also spend a lot of time cruising around chasing everything that enters their territory.”
Contrary to popular opinion, carpenter bees don’t consume wood. If you don’t want them around, paint or varnish your wood. You can also plug their (unoccupied) holes with steel wool or caulk, or screen the holes so they don’t return.
The female and male carpenter bees that nectar the salvia (sage) in our bee friendly garden are about the size of bumblebees. “Robust” comes to mind. Okay, fat. They’re fat.
Their abdomens are bare and a shiny black. If you photograph them, you’ll see your own reflection. It’s like seeing your reflection in a black Lamborghini.
The female carpenter bees are a solid black, while the male carpenter bees are lightly colored around the head.
In comparison, bumblebees have hairy abdomens with at least some yellow markings.
If I were a carpenter and you were a…nah, I’d rather be a bumblebee./o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>/o:p>