- (Focus Area) Yard & Garden
- Author: Kathy Keatley Garvey
We miss the late Robbin Thorp, 1933-2019, distinguished emeritus professor of entomology at UC Davis, who co-authored Bumble Bees of North America: an Identification Guide (Princeton University Press, 2014).
He loved to share his expertise on bumble bees, which originated more than 100 million years ago. But their distribution and diversity are not well known, he used to tell us.
Bumble bees are just one of the some 20,000 species of bees that populate the world. Of that number, however, only about 250 species are bumble bees, and they all belong to the genus Bombus.
Some 46 different species of bumble bees reside in North America, north of Mexico, Thorp related for a Bug Squad blog posted on July 10, 2014.
In their book, lead author Paul Williams and co-authors Thorp, Leif Richardson and Sheila Colla published information about bumble bees and their history, plant favorites, distribution maps, up-to-date taxonomy, and extensive keys to identify the many color patterns of the species.
They list sites to spot bumble bees:
- farms and gardens with a diversity of flowering crops and herbs
- hay fields
- roadside ditches
- windbreaks with good abundance and diversity of “weedy” flowering plants, such as clovers and vetches
- wetlands and wet meadows
- hardwood forests
- mountain meadows, and
- urban parks and gardens
The primary species found in Yolo County, Thorp related, are:
- Yellow-faced bumble bee, now known as the Vosnesensky bumble bee, Bombus vosnesenskii
- Yellow bumble bee, Bombus californicus, now known as Bombus fervidus
- Black-tailed bumble bee, Bombus melanopygus, formerly known as Bombus edwardsii. This is the first to fly in the winter and spring.
- Crotch bumble bee, Bombus crotchii, a short-tongued species
- Van Dyke bumble bee, Bombus vandykei, a medium long-tongued species
Lately we've been observing B. vosnesenskii, and B. fervidus, B. melanopygus in our pollinator garden in Vacaville, Solano County.
Currently, B. fervidus favors the rock purslane, Calandrina grandiflora. What a joy to see!
- Author: Lauren Fordyce
Aedes mosquitoes can transmit some of the most debilitating and deadly mosquito-borne pathogens to humans, such as Zika virus, dengue virus, chikungunya virus, and yellow fever virus. One Aedes species is also capable of transmitting heartworm to dogs. These invasive mosquitoes are now present in many regions of California, from Shasta County to San Diego County. View a map of Aedes distribution by county.
The yellow fever mosquito (Aedes aegypti), the Asian tiger mosquito (Aedes albopictus), and the Australian backyard mosquito (Aedes notoscriptus) are unlike most native mosquitoes. They prefer to bite during the day, especially around your legs and ankles. Adults are black with white stripes on their legs and back.
Many Aedes mosquitoes live in close contact with people and can breed in backyards and even inside homes. They are known as “container breeding mosquitoes” because they lay eggs in small containers, such as flowerpots or old tires. Eggs are laid in moist areas just above the water surface, can overwinter, and are resistant to drying so may remain viable for months or longer.
How can you protect yourself?
In many areas of California, public Mosquito and Vector Control Districts aim to keep mosquito numbers down to tolerable levels. You can aid their efforts by eliminating mosquito breeding sources around your home. This includes keeping fine mesh screens on windows and doors in good condition, draining standing water or treating it with Bacillus thuringiensis subspecies israelensis (Bti), and wearing mosquito repellents and protective clothing outdoors.
Learn more about invasive Aedes mosquitoes and how to protect yourself by visiting the following resources:
- UC IPM Pest Notes: Mosquitoes: https://ipm.ucanr.edu/PMG/PESTNOTES/pn7451.html
- Mosquito repellent information from the California Department of Public Health: https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/Mosquito-Repellent.aspx
- Interactive map of Aedes distribution in California: https://cdphdata.maps.arcgis.com/apps/webappviewer/index.html?id=57367199287a4d18a2cecf107854255b
- Invasive Aedes fact sheet from the Mosquito and Vector Control Association of California: https://acrobat.adobe.com/id/urn:aaid:sc:US:908f4b9e-8266-47b3-9e3d-ec165913fc7f?viewer%21megaVerb=group-discover
- Author: Kathy Keatley Garvey
In images, text, and analogies.
“Just like in a honey bee colony, it takes a team to win an award," he said, and graciously proceeded to thank all those who made it possible. Family, friends, students, postdoctoral fellows, colleagues, staff and more. Or, as he said "work performed by the cast of thousands deserve the distinguished research award."
Leal, former professor and chair of the Department of Entomology (now the Department of Entomology and Nematology) joined the Department of Molecular and Cellular Biology faculty in 2013. He is first UC Davis faculty member to win Academic Senate's trifecta of coveted awards: Distinguished Teaching Award for Undergraduate Teaching (2020), Distinguished Scholarly Public Service Award (2022) and now, the Faculty Distinguished Research Award.
A week before the seminar, Leal was elected to the National Academy of Sciences.
“Dr. Leal is an internationally recognized entomologist and a world leader in his field for his groundbreaking and transformative research in insect olfaction and chemical ecology,” said UC Davis distinguished professor Bruce Hammock, who nominated Leal for the Faculty Distinguished Research Award.
Leal credits Hammock, a 25-year friend and colleague, as instrumental in “luring” him from his tenured position in the Ministry of Agriculture, Forestry, and Fisheries, Japan, to the Department of Entomology (now the Department of Entomology and Nematology) in 2000. A native of Brazil, Leal received his Ph.D. in applied biochemistry from the University of Tsukuba, Japan, with subsequent postdoctoral training in entomology and chemical ecology at the National Institute of Sericultural and Entomological Science and Cornell University, respectively.
In his letter of nomination, Hammock pointed out "I especially applaud him for elucidating the mode of action of the insect repellent DEET, developed in 1946 and known as ‘the gold standard of repellents.' Its mode of action remained an enigma for six decades until Walter's discovery. In researching the neurons in mosquito antennae sensitive to DEET, he isolated the first DEET-sensitive odorant receptor, paving the way for the development of better repellents.”
Leal's analogy of bees working together to succeed, just like what occurs in a successful lab, is spot on. The worker bees inside the hive perform specific duties: nurse maids, nannies, royal attendants, builders, architects, foragers, dancers, honey tenders, pollen packers, propolis or "glue" specialists, air conditioning and heating technicians, guards, and undertakers.
As an aside, Leal mentioned that one research project in his lab involved his daughter Helena, honey bees and her shampoo. “Helena always said the bees were bothering her and then when we collected the volatiles from her, we noticed that there was a contaminant, isoamyl acetate,” Leal told the crowd. “To make a long story short, isoamyl acetate is a chemical that elicits a very aggressive behavior. It's called a sting pheromone known from the early 1960s, and we figured out that that chemical was coming from a shampoo that she was using at that time--the so-called Aussie. So, she stopped using that shampoo and there was no problem with the bees anymore.”
Read more about his lecture here and watch his lecture at https://youtu.be/HkfhsYQE5bI.
- Author: Lauren Fordyce
Help increase public awareness of invasive species and encourage participation in the ongoing fight against invasive species by celebrating California Invasive Species Action Week (CISAW) June 1- 9, 2024.
Invasive species include non-native plants, animals, and pathogens that can negatively impact our waters, native ecosystems, agriculture, health, and economy. Every day this week, UC IPM will share information spotlighting a different invasive species, its impacts, and what you can do to help.
Keep an eye out for our upcoming blog posts and check out the resources below to learn more about invasive species:
- Read UC IPM's previous blog posts on invasive species.
- Buy firewood where you burn it. Moving firewood can transport many invasive pests to new areas. Visit the California Firewood Task Force for more information.
- Learn about pest quarantines in your area from the California Department of Food and Agriculture.
- Don't plant invasive species and when possible, try to plant California natives. Visit the PlantRight website for more information on plant selection.
- Report invasive species to your local County Agricultural Commissioner. Contact information for your location can be found at the California Department of Agriculture County/State Liaison page.
- Watch a webinar. June 3-7th UC ANR will be hosting lunchtime webinars to discuss various invasive species and the work being done to combat them. To learn more and register, visit the Invasive Species Lunchtime Talks website.
To learn more about events scheduled for California Invasive Species Action Week and to view more ways you can help, go to https://wildlife.ca.gov/Conservation/Invasives/Action-Week.
A beautiful tree sits on the north side of Little Chico Creek, shading the picnic table at site #34 in Lower Bidwell Park. Its thick, smooth lower branches are perfect for climbing, and its form is both rounder and more symmetrical than its relatives at higher elevations. And its occurrence at our low altitude (elevation 197 feet) is rare.
Captain George Vancouver of the British Royal Navy commanded a voyage of exploration and diplomacy from 1791 to 1795 which circumnavigated the globe and made contact with five continents. Madrone's species name honors the Scottish surgeon, botanist and naturalist, Archibald Menzies, who noted this tree during Vancouver's voyage of exploration. Menzies, who spent many years at sea serving with the Royal Navy and on private merchant ships, recognized its similarity to the European arbutus, A. unedo, which today is a popular landscape tree in Chico. Its red fruits are shaped like strawberries, and in fact the Spanish word madroño translates as “strawberry tree.” Other common names include madroa, madroo, madroña, and bearberry.
While all parts of the Pacific madrone are remarkable, its best-known characteristic is that it freely peels its outer bark. Once this skin-like outer layer is shed, the remaining bark is smooth and polished, with a distinctive reddish color. Young bark darkens to a deep red with age; younger stems can range from green to chartreuse, and young trunks are frequently orange. Older portions of the bark become a dark, brownish red. The deep color of the bark contrasts nicely with the tree's large, glossy, dark green foliage. In spring, sprays of small, bell-shaped white flowers adorn the branches, giving way to red berries in the autumn months.
The madrone has evolved an effective method of seed regeneration: each berry contains between three and 30 seeds, and when the berries dry they develop hooked barbs that can latch onto the fur and skin of passing mammals, hitching a ride to colonize new locations.
The Pacific madrone ranges in height from about 33 to 82 feet but can reach up to 100 feet or more in ideal conditions. In those perfect conditions, it can reach a thickness of 5 to 8 feet at the trunk, much like an oak tree. Ideal conditions include a sunny site such as a south or west facing slope with soil that is well drained and lime free.
The largest known specimen of Pacific madrone lived in Joshua Creek Canyon Ecological Reserve on the Big Sur Coast. At least 125 feet tall and more than 25 feet in circumference, and listed on the American Forests National Big Tree list, it sadly was severely burned in the 2016 Soberanes Fire.
Surviving Drought and Fire: At the base of its trunk, the Pacific madrone has a woody, globe-shaped, regenerative organ known as a burl. This structure is a peculiar adaptation to its forest habitat, which historically experienced regular burns at intervals averaging between 10 and 35 years. The Pacific madrone is susceptible to fire, but also relies on fire to regenerate. Its low resistance to fire is due to its thin bark. Conversely, repeated top-kill by fire encourages burl development, enhancing Pacific madrone survival - the burl serves as a source of stored carbohydrates for prolific postfire sprouts. These rise from dormant buds on the burl, and initially grow rapidly after a fire.
A massive, wide-spreading root system increases its ability to withstand summer drought. In fact, the tree prefers dry, well-draining soils and does not tolerate direct watering during the summer months. Once established, Pacific madrone is windfirm, drought enduring, and somewhat tolerant of wet, freezing conditions.
Native American Uses: The Concow tribe calls the tree dis-t?'-tsi or kou-wät′-chu. Native Americans sometimes ate the berries, but were more likely to make them into a type of cider, or chewed them to cleanse their mouths, since the berries' high tannin content makes them astringent. Madrone berries were used in necklaces and other decorations, and as bait for fishing. Tea made from the bark and leaves was used to treat stomach aches, cramps, skin ailments, and sore throats. The wood was used to make implements and it was particularly useful as firewood; its density and hardness ensures it burns long and hot -- even better than oak.
Pacific madrone is a particularly beautiful tree, with its reddish curved trunks supporting a broad, spreading crown of deep green leaves. It is most often seen as a single specimen tree displaying its finery among the more common Douglas fir and tanoak. It is currently declining throughout most of its range, unfortunately due to 100 years of forest fire control and urban development in its native habitat. We are lucky to have our lovely, rare specimen in Lower Bidwell Park.
UC Master Gardeners of Butte County are part of the University of California Cooperative Extension (UCCE) system. To learn more about us and our upcoming events, and for help with gardening in our area visit our website. If you have a gardening question or problem, email the Hotline at mgbutte@ucanr.edu or leave a phone message on our Hotline at 530-552-5812. To speak to a Master Gardener about a gardening issue, or to drop by the MG office during Hotline hours, see the most current information on our Ask Us section of our website.