From the UC Blogosphere...
Looking for love...or a fast-food snack...or a little sun... A male flameskimmer dragonfly, Libellula saturata, is a sight...
A male flameskimmer dragonfly, Libellula saturata, perches on a bamboo stake in Vacaville, Calif. (Photo by Kathy Keatley Garvey)
The flameskimmer's wings shimmer in the morning light. (Photo by Kathy Keatley Garvey)
Congrats to Jessica Gillung for a well-deserved honor! Gillung, a postdoctoral fellow at Cornell University and a UC Davis...
As a graduate student at UC Davis, Jessica Gillung participated in many outreach programs with the Bohart Museum of Entomology. (Photo by Kathy Keatley Garvey)
Milkweed by Linda Lewis Griffith UCCE Master Gardener Common Name: California...
Bugs from the Bohart Museum of Entomology, UC Davis, grabbed the interest of fairgoers at the 144th annual Dixon May Fair,...
Entomologist Jeff Smith (left) shows insect displays from the Bohart Museum of Entomology to fairgoers last Saturday at the Dixon May Fair. (Photo by Kathy Keatley Garvey)
Entomologists Alex Dedon (left) and Jeff Smith of UC Davis engage with Carolyn Jones of Dixon, who served as chair of the 2019 Sacramento Orchid Show. (Photo by Kathy Keatley Garvey)
Forensic entomologist Alex Dedmon, a doctoral student at UC Davis, responds to a question from a fairgoer Saturday at the Dixon May Fair. (Photo by Kathy Keatley Garvey)
This fairgoer checked out the specimens of carpenter bees, honey bees, leafcutting bees and sweat bees from the Bohart Museum of Entomology at the Dixon May Fair. (Photo by Kathy Keatley Garvey)
An insect display on Hymenotpera (bees and wasps) drew the interest of this fairgoer at the Dixon May Fair. (Photo by Kathy Keatley Garvey)
Specimens from the order Coleoptera (beetles) fascinated many fairgoers at the Dixon May Fair. (Photo by Kathy Keatley Garvey)
Camouflaged insects include stick insects that look like leaves. (Photo by Kathy Keatley Garvey)
Butterfly specimens from the order Lepitoptera (butterflies and moths) brightened the Bohart Museum of Entomology display at the Dixon May Fair. (Photo by Kathy Keatley Garvey)
The Floriculture Building at the Dixon May Fair was more than flowers--it included specimens of pollinators and other insects from the Bohart Museum of Entomology. (Photo by Kathy Keatley Garvey)
Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
MGCC Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk. You asked about carpenter bees boring a hole in your roof beams and how to get rid of them without killing them. From your description and the description of the holes, it does indeed seem likely they are carpenter bees, but we would recommend getting a positive identification before taking control measures. These very large bees with a loud buzz are quite obvious, the females being large and shiny black. The males are those beautiful golden fuzzy 'teddy bear' bees. You may also see pollen-laden bees entering the hole to feed their babies!
Only the females build nests, boring a tunnel into soft wood, leading to one or several nest cavities. They do not create hives, but several females may use the same tunnel for the nest. They mate and lay eggs in the spring, the young bees developing over several months - there is only one generation each year. These bees can indeed damage wood structures, but unless there are many holes you probably have time to consider control methods. As you do not want to kill them, and there may be young brood inside the nest at this point, you might want to wait until late summer after the bees have emerged. Then you can plug the holes and paint or stain the wood to discourage any further nesting.
Here are some UC links with more information on this bee, and how to manage them.
We couldn't find any information on how to remove them without killing them - it also seems that even if the adults are excluded, the young bees can chew their way out of the nest after they hatch. So if you can wait, I think you would be fine waiting until later in the summer to paint and fill the holes, and then hopefully they will cause no further problems. Meanwhile, enjoy these beautiful and useful creatures in your garden.
If you are a DIY person, there are plenty of articles found via Google for fixing the holes as well as techniques to assure that the bees don't come back (they can be homing to their birthplace). And there may be contractors around that specialize in "fixing" the problem.
Good luck with this!
Help Desk of the UC Master Gardener Program ofContraCosta County (SMW)
Note: UC Master Gardeners Program of Contra Costa's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, email: email@example.com, or on the web at http://ccmg.ucanr.edu/Ask_Us/. MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog.