- Author: Kathy Keatley Garvey
It's Thanksgiving Day, and as we sit down with family and friends to count our blessings, let's thank the bees.
If your table includes pumpkin, cranberries, carrots, cucumbers, onions, apples, oranges, cherries, blueberries, grapefruit, persimmons, pomegranates, pears, sunflower seeds, and almonds, praise the bees for their pollination services.
Honey bees (Apis mellifera) are generalists, while the squash bees (Peponapis pruinosa) are specialists that pollinate only the cucurbits or squash family, Cucurbitaceae.
And don't forget the spices. Honey bees visit the plants that eventually comprise our spices, including sage, basil, oregano and thyme.
Ready for dessert? Ice cream? Even milk and ice cream are closely linked to the honey bee. Cows feed on alfalfa, which is pollinated by honey bees (along with other bees).
Happy Thanksgiving!
![A squash bee, Peponapis pruinosa, pollinating a squash blossom. (Photo by Kathy Keatley Garvey) A squash bee, Peponapis pruinosa, pollinating a squash blossom. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/96180.jpg)
![Five honey bees offering their pollination services on a pomegranate blossom. (Photo by Kathy Keatley Garvey) Five honey bees offering their pollination services on a pomegranate blossom. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/96181.jpg)
- Author: Kathy Keatley Garvey
If you've ever been asked that, you may have responded--quite politely--"Small, thank you!"
You probably didn't thank the squash bees.
But as we celebrate Thanksgiving with family and friends, let's remember that squash bees probably pollinated the pumpkin that ended up as a pie on your table.
The squash bee, Peponapis pruinosa, is a specialist that pollinates only the cucurbits or squash family, Cucurbitaceae, which includes pumpkins, squash, gourds, cucumbers and zucchini. P. pruinosa is a species of solitary bee in the tribe Eucerini, the long-horned bees. There's also another genera, Xenoglossa.
Squash bees are early risers, rising before the sun does. They begin pollinating the blossoms as soon as they open. Other bee species, such as honey bees (which are non-natives), don't visit the flowers so early.
Around noon, the blossoms close for the day, so there's a limited time for pollination--and a limited time to admire and photograph them.
The females are ground nesters. "The males sleep in the blossoms at night and wait for the females to arrive," the late late Robbin Thorp (1933-2019), UC Davis distinguished emeritus professor of entomology, told us.
Another attribute: The squash bee is a native of North America, unlike the honey bee.
"Before Europeans brought honey bees to the New World, squash bees were busy aiding the adoption, domestication, spread, and production of squashes and gourds by indigenous peoples throughout the Americas," according to an article by USDA research entomologist James Cane.
"Hey, there, pumpkin, do you want another piece of pie, pollinated by our native bees, the squash bees?"
![The squash bee, Peponapis pruinosa, is a specialist that pollinates only the cucurbits or squash family, Cucurbitaceae. (Photo by Kathy Keatley Garvey) The squash bee, Peponapis pruinosa, is a specialist that pollinates only the cucurbits or squash family, Cucurbitaceae. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/87458.jpg)
![Close-up of a squash bee. Native to North America, it pollinates cucurbit blossoms early in the morning. The blossoms usually close around noon. (Photo by Kathy Keatley Garvey) Close-up of a squash bee. Native to North America, it pollinates cucurbit blossoms early in the morning. The blossoms usually close around noon. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/87459.jpg)
- Author: Kathy Keatley Garvey
Yes, hummingbirds are pollinators, too!
A capacity crowd of 250 will attend the fourth International Pollinator Conference, to be hosted by the University of California, Davis, from Wednesday, July 17 through Saturday, July 20 in the ARC Ballroom.
A welcoming reception took place from 6:30 to 8 tonight (Wednesday) in the Good Life Garden at the Robert Mondavi Institute, 392 Old Davis Road.
Themed “Multidimensional Solutions to Current and Future Threats to Pollinator Health,” the conference will cover a wide range of topics in pollinator research: from genomics to ecology and their application to land use and management; to breeding of managed bees; and to monitoring of global pollinator populations.
Co-chairs are pollination ecologist Neal Williams and Extension apiculturist Elina Lastro Niño of the UC Davis Department of Entomology and Nematology. The UC Davis Honey and Pollination Center, directed by Amina Harris, is coordinating the conference. Events manager Elizabeth Luu serves as the conference coordinator.
Keynote speakers are Lynn Dicks, Natural Environment Research Council (NERC) Research Fellow, School of Biological Sciences, University of East Anglia, England, and Christina Grozinger, distinguished professor of entomology and director of the Center for Pollinator Research, Pennsylvania State University, (the research center launched the pollinator conferences in 2012).
Dicks will speak at 9 a.m., Thursday, July 18 on "The Importance of People in Pollinator Conservation" while Grozinger will address the crowd at 9 a.m., Friday, July 19 on "Bee Nutritional Ecology: From Genes to Landscapes."
Dicks, an internationally respected scientist, studies bee ecology and conservation. She received the 2017 John Spedan Lewis Medal for contributions to insect conservation. Grozinger studies health and social behavior in bees and is developing comprehensive approaches to improving pollinator health and reduce declines.
Among the speakers is Rachel Vannette, assistant professor, UC Davis Department of Entomology and Nematology, who will discuss her hummingbird research.
The agenda:
Wednesday, July 17
- 6:30 to 8 p.m.: Early Registration and welcome reception in the Good Life Garden at the Robert Mondavi Institute, 392 Old Davis Road, Davis.
Thursday, July 18
6:45 to 8:30 a.m., breakfast at Segundo Dining Commons
8:45 a.m. Opening remarks and welcome
9 a.m. Keynote Address: "The Importance of People in Pollinator Conservation" by Lynn Dicks, School of Biological Sciences, University of East Anglia, UK
10 a.m. Session 1: Novel Quantitative Methods in Pollinator Ecology & Management
- "The Role of Bee and Non-Bee Pollinators in Australian Open and Protected Cropping Systems (How do we overcome the pollination challenges?)" - Romina Rader, University of New England, Australia
- "Implementing a Honeybee Foraging Model and REDAPOLL Fruit Set Predictions in Washington State's Decision Aid System" - Vince Jones, Washington State University
- "Using DNA metabarcoding techniques to improve plant-pollinator interaction networks" - Victoria Reynolds, University of Queensland, Australia
- "Citizen Science Data for Mapping Bumblebee Populations" - Claudio Gratton, University of Wisconsin
11:15 to 11:30: Break (Light refreshments in the foyer) - "From Theory to Practice: The Bumble-BEEHAVE Model and its Application to Enhance Pollinator Friendly Land Management" - Matthias Becher, University of Exeter, UK
- "A Laboratory System to Study the Effects of Stressors on Honey Bee Health and Fecundity" - Julia Fine, USDA-ARS Davis, Calif.
- "Using Automated Tracking to Link Individual Behavior to Colony Performance in Bumble Bees" - James Crall, Harvard University
Lunch at Segundo Dining Commons (opens from 11:30 a.m. - 1:30 p.m.)
1:45 p.m. Session 2: Drivers of Host-Pathogen Interactions
- "DWV as a Driver of Host Bee Decline" - Robert Paxton, Martin-Luther University, Germany
- "Novel Transmission Routes and Intensification as Drivers of Disease Emergence and Virulence in Honey Bee viruses" - Mike Boots, UC Berkeley
- "Viral Transmission in Honey Bees and Native Bees Supported by a Global BQCV Phylogeny" - Elizabeth Murray, National Museum of Natural History, Smithsonian Institution
3 to 3:15: Break (Light refreshments in the foyer)
- "Drivers of Pathogen Distributions in Feral and Managed Honey Bees" - Panuwan Chantawannakul, Chiang Mai University, Thailand
- "Serratia marcescens, a Pathobiont of Honey Bees?" - Kasie Raymann, University of North Carolina Greensboro
- "Foreign Fungi in Native Bees across the Commonwealth of Virginia" - Kathryn LeCroy, University of Virginia
- "Traits as Drivers of Plant-Pollinator-Pathogen Networks" - Quinn McFrederick, UC Riverside and Scott McArt, Cornell University
4:30 p.m.: Poster Session 1 in the ARC Ballroom - 6:30 to 8 p.m. Opening Reception
Robert Mondavi Institute Sensory Building, 392 Old Davis Road, Davis
Honey Tasting led by Amina Harris, director, Honey and Pollination Center
Friday, July 19
6:45 a.m. to 8:30 a.m., Breakfast at Segundo Dining Commons
9 a.m. Keynote: "Bee Nutritional Ecology: From Genes to Landscapes," by Christina Grozinger, Penn State University
10 a.m. Session Three: Variable Climates and Changing Pollinators
- "Bee Responses to Climate Change: from Micro- to Macroecology" - Jessica Forrest, University of Ottawa, Canada
- "A Climate Vise of Temperature Extremes May Explain Past and Predict Future Bumble Bee Range Shifts" - Michael Dillon, University of Wyoming
- "Climate Change Effects on Megachilidae Bee Species along an Elevation Gradient" - Lindsie McCabe, Northern Arizona University
10:15 to 11:05: Break (Light refreshments in the foyer) - "Testing the Phenological Mismatch Hypothesis for a Plant-Pollinator Iinteraction" - Charlotte de Keyzer, University of Toronto, Canada
- "Phenological Mismatch between Bees and Flowers Early in the Spring and Late in the Summer" - Gaku Kudo, Hokkaido University, Japan
- "Climate Change Impacts on Brazilian Pollinators" - Tereza (Cris) Giannini, Federal University of Para, Brazil
- "Pollinator Health in a Commercial Blueberry System" - Lief Richardson, University of Vermont
Lunch at Segundo Dining Commons (opens from 11:30 a.m. - 1:30 p.m.)
Optional Discussion: How do you relate your science to justice, equity and advocacy issue
1:45 Session 4: Causes and Consequences of Pesticide Use: From Use Patterns to Pollination Services
- "A New Framework for Environmental Risk Assessment of Pesticides" - Francisco Sánchez-Bayo, University of Sydney, Australia
- "Potency Paradox: Patterns and Drivers of Insecticide Use in U.S. Agriculture" - Maggie Douglas, Dickinson College
- "Estimating Pollinator Pesticide Exposure" - Maj Rundlof, Lund University, Sweden
Break (Light refreshments in the foyer) - "A Risk Assessment of Neonicotinoid Insecticides in New York" - Travis Grout, Cornell University
- "Risk of Exposure in Soil and Sublethal Effects of Systemic Insecticides Applied to Crops on Adult Female Ground-Nesting Bees Using the Hoary Squash Bee as a Model Species" - D. Susan Willis Chan, University of Guelph, Canada
- "Delayed Lethality: The Effects of a Widely-Used Fungicide on Honey Bees (Apis mellifera)" - Adrian Fisher II, Arizona State University
- "Sub-lethal Impacts of Pesticides on Bees" - Troy Anderson, University of Nebraska
Poster Session 2 and Networking at the ARC Ballroom
Saturday, July 21
8 a.m. Registration at the ARC Ballroom
6:45 a.m. to 8:30 a.m.: Breakfast at Segundo Dining Commons
9 a.m.: Session 5: Integrative Approaches to Improving Bee Health Across Landscapes
- "Combining Physiological and Ecological Data for More Effective Bee Protection and Conservation" - Cedric Alaux, INRA, France
- "Keeping Bees in a Warming World: Protein Biomarkers for Heat Stress and Queen Failure Diagnostics" - Alison McAfee, North Carolina State University
- "Factors Influencing Colony Survival in Migratory Beekeeping Based on Honey Bee Resistance Traits" - Michael Simone-Finstrom, USDA-ARS, Baton Rouge, Louisiana
- "Temporal and Spatial Dynamics of Pollinator Communities across North Carolina Agroecosystem" - Hannah Levenson, North Carolina State University
- "The Effects of Land Cover on Habitat Quality for Nesting Bumble Bees" - Genevieve Pugesek, Tufts University
10 to 10:15 a.m. Break (Light refreshments in the foyer) - "Improving Bee Health in Canola Pollination" - Shelley Hoover, Alberta Agriculture and Forestry
- "Mitigating Land Use Decisions that Destroy Bee Forage" - George Hansen, Foothills Honey, Oregon, USA
- "Impact of Landscape-Scale Floral Resources Availability on Pollinator Communities" - Aaron Iverson, Cornell University
- "Why are Crops Mainly Visited by Broadly Polylectic Bee Species?" - Katja Hogendoorn, The University of Adelaide, South Australia
12:15 Lunch
1:40: Session 6: Pollinators in Urban Environments
- Presentation by The Wonderful Company
- Honoring new California Master Beekeeper graduates - Elina Niño, UC Davis
- "Floral Trophic Ecology of a North American Metropolis Revealed by Honey Bee Foraging Assay" -
Doug Sponsler, Penn State University - "Pollinators and Urban Warming: A Landscape Physiology Approach" - Elsa Youngsteadt, North
Carolina State University - "Green Infrastructure to Support Urban Wild bees: Communicating Science to Practitioners" - Scott
McIvor, University of Toronto, Canada - "Urban Pollinator Conservation Opportunities: Integrating Research with Policy and Practice" -
Katherine Baldock, University of Bristol, UK - "Linking Pollinator Health, Microbiome Composition and Human Provisioning in Anna's Hummingbird
(Calypte anna) - Rachel Vannette, UC Davis
Break (Light refreshments in the foyer) - "Beekeeping Ordinances: Protecting bees and Neighbors" - Tracy Ellis, San Diego County
Department of Agriculture - "Beekeeping in the City: Successes and Challenges" - Charlie Blevins, San Francisco Beekeepers'
Association - "Electric Power Companies Protecting Pollinators" - Jessica Fox, Electric Power Research Institute,
Palo Alto - "The Effect of Land use on a Sexually Selected Characteristic of the Cabbage White Butterfly (Pieris
rapae) in the United States" - Anne Espeset, University of Nevada, Reno - "Urban Pollinator Conservation: Bee Campus USA and Bee City USA as a Model for Meaningful
Community Engagement" - Phyllis Stiles, Xerces Society for Invertebrate Conservation, Portland,Ore.
(There are no plans to video-record the conference, according to Elizabeth Luu (luu@caes.ucdavis.edu) of the UC Davis Honey and Pollination Center, the events coordinator for the conference.)
![A longhorned bee flies over a Mexican sunflower blossom (Tithonia) in Vacaville. (Photo by Kathy Keatley Garvey) A longhorned bee flies over a Mexican sunflower blossom (Tithonia) in Vacaville. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/61778.jpg)
![A squash bee, a specialist bee that forages on the genus Cucurbita, buzzes out of squash blossom in Vacaville, Calif. (Photo by Kathy Keatley Garvey) A squash bee, a specialist bee that forages on the genus Cucurbita, buzzes out of squash blossom in Vacaville, Calif. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/61779.jpg)
![A honey bee (Apis mellifera) and a yellow-faced bumble bee (Bombus vosnesenskii) share a flower on the UC Davis campus. (Photo by Kathy Keatley Garvey) A honey bee (Apis mellifera) and a yellow-faced bumble bee (Bombus vosnesenskii) share a flower on the UC Davis campus. (Photo by Kathy Keatley Garvey)](/blogs/blogcore/blogfiles/61780.jpg)
By Penny Pawl, UC Master Gardener of Napa County
When you are planning your summer garden, remember the pollinators. Bees and other pollinators are in trouble in California and across the U.S. and need our help. They are nectar feeders so put in plenty of blooming plants for them.
Without pollinators we would lose many food crops. There are 1,000 species of California native bees. Twenty-six of these are bumblebees and most of the rest are solitary bees.
The pollinators native to our area have evolved with the native landscape so it's important to have some native plants in your garden. Pollinators include native bees and butterflies. Honeybees are not native to the United States but were introduced for their honey. However, other pollinators are just as effective. Let me introduce you to some of our native bees.
For several years, I have created nests for the native mason bees. These nests consist of pieces of wood with 3/8-inch holes drilled into them. The one they visit most is a piece of firewood. Mason bees have nested in it repeatedly. I know they were there because of the mud in each hole.
Last year I actually saw the bees leaving their nests and then returning. They are about to come out this spring to pollinate the fruit trees. They don't spend much time flying around before they start building new nests for their babies.
The mason bee creates its nest in long narrow tunnels within the wood. The bees do not make these tunnels; they find them and move in. So I drilled the holes for them. The bees pack the holes with pollen, lay an egg, pack in more pollen and lay another egg. They put three to five eggs per hole depending on the depth. When they are done laying, around the first of April, they seal the holes with mud. I know the nest is full when I see mud in every hole. The eggs hatch the following spring.
This year I did not move the nest to a sheltered location. It appears that woodpeckers have tried to drill out the nest. I will wait and see how much damage the birds have done by the end of March.
I have bumblebees in my garden every year. They especially love my ‘Hot Lips' salvia from Mexico. They spend all day gathering nectar and are gentle.
Bumblebees nest in the ground. You should always leave a cleared area in your garden for them; they will not nest in mulch. I often find their little mounds. When they are done digging, you cannot tell they were even there. They love one particular area of my garden that I always keep clear of mulch.
I also see a lot of carpenter bees, the big bees that drill for nectar in the back of the flower. They are gentle and you can observe what they are doing easily.
They can be destructive when they drill into untreated lumber. I had them in my hothouse one year. They had drilled all the way to the end of a 12-foot-long 4 x 2 board. I had to replace that wood and paint it with latex to keep them out. Putting steel wool in the holes will also stop them. They do need a place to lay their eggs, however.
The male carpenter bee is a big brown teddy bear. He has only one purpose: to pursue females. He does not sting. I had a visit from one a few years back and he hung around me for a while. Once their mating duty is done, they die.
Digger bees and squash bees both nest in the ground. Squash bees emerge to pollinate squash and gourds. They are only present when these plants are in bloom. Even so, I hand-pollinate my squash to make sure I get fruit.
Bumblebees are said to buzz tomatoes, which are self-pollinating. Just to be sure the flowers do pollinate, I shake the vines every morning when I do my walk-through.
To lure pollinators to your garden, plan to have a variety of plants blooming every month of the year.
Workshop: UC Master Gardeners of Napa County will hold a workshop on “Growing Tomatoes” on Saturday, April 6, from 9:30 a.m. to 11:30 a.m. at University of California Cooperative Extension, 1710 Soscol Avenue, Napa.
Join our experienced tomato growers for tips and tricks on cultivating perfect homegrown tomatoes. Learn the latest research on tomato cultivation and care, and discover new and heritage tomato varieties. You'll get all the information you need to grow delicious and beautiful tomatoes in your own large or small garden or in containers. Growing America's favorite garden fruit is not only fun and easy, but also the best way to acquire healthy food for you and your family. Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County (http:/napamg.ucanr.edu) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
![California bumblebee (UC ANR) California bumblebee (UC ANR)](/blogs/blogcore/blogfiles/58799.jpg)
Few other vegetables are more representative of fall than pumpkins. Come October, mounds of pumpkins of various shapes and sizes are a common sight in Napa Valley. While they may seem to suddenly appear, pumpkins have a fairly long growing season. If you are considering growing pumpkins in your garden for a fall harvest, it's time to plant.
Pumpkins belong to a large botanical family that includes melons, cucumbers and other squash. Some tiny pumpkin varieties can fit in the palm of your hand. The record-setting types weigh in at over a ton. Pumpkins also come in shades beyond jack-o-lantern orange. For an unusual addition to your garden, seek out white, red or blue-skinned varieties.
One bonus of planting pumpkins is that they attract bees. Honeybees will happily do the work of pollination, but a garden with a range of plants will lure and nurture other bee species. Squash bees tend to fly early in the morning, before honeybees get going. You may never even know that they have visited your garden. To encourage squash bees, consider adopting a no-till regimen. Squash bees nest several inches below the soil, and frequent tilling can destroy their habitat and nesting populations.
It is a joy to watch pumpkins grow, but they do need space. If your garden has ample room, allowing the plants to ramble can help shade and cool the surrounding soil and prevent weeds from growing. Before planting, amend the soil with compost to get plants off to a healthy start. Plants can be started in small pots or direct-seeded. If you are aiming for maximum size, feed with a high-nitrogen fertilizer to stimulate leaf growth. When blooms appear and fruit set occurs, phosphorus and potassium become more important.
Once established, pumpkins grow fast. To promote larger pumpkins, select one or two good specimens and remove all others on the vine. This pruning will help the plant transfer nutrients to the remaining units.
Squash leaves can be susceptible to mildew. Irrigating with drip or soaker hose is preferable to overhead watering. Remove diseased leaves as soon as possible and do not overwater. Leaves may wilt on hot days but typically recover as the weather cools. If wilting persists, check to make sure plants have adequate water
Common pumpkin pests include cucumber beetles and vine borers. A home gardener can tolerate some damage rather than resorting to chemical sprays. Remember that pollinators and other beneficial insects might be frequenting the plant, too. Use light-permeable row covers to protect plants if an infestation is particularly heavy.
Trap crops can also help reduce insect damage by providing an alternative food source. Crop rotation can help by eliminating available food sources for future generations of pests. The University of California's Integrated Pest Management database is an excellent resource for pest- and disease-control advice.
Besides being delicious, pumpkins have other advantages for the home gardener. They can help minimize weed growth around taller plants such as sunflowers. Native Americans understood the wisdom of planting pumpkins with beans; the beans add nitrogen to the soil and pumpkins are heavy feeders. Many pumpkins store well and can provide tasty meals in winter when many vegetables are out of season.
You don't have to wait for the pumpkin to mature before enjoying the plant. The leaves are edible and can be cooked like spinach. Choose young, tender leaves for that purpose. Of course, the seeds are edible, too. Enjoy them roasted and salted to increase the food value of your crop, particularly if you have limited space. Saving seeds and swapping with friends can increase your garden's diversity with no extra expense.
Pumpkins grow well in Napa Valley. Consider planting a beautiful heirloom cultivar to enjoy as a table centerpiece in winter. Between the pumpkin's tasty flesh, its seeds and its nutritious leaves, this plant hits a triple.
Workshop: U.C. Master Gardeners of Napa County will hold a workshop on “Succulent Plant Success” on Saturday, July 7, from 9:30 a.m. to 11:30 a.m., at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Bring your love of succulents to this workshop dedicated to helping succulent gardeners grow the show-stopping plants we all hope for. Master Gardeners will show you the right kind of soil and containers and how to care for your succulents. They will also discuss myriad succulent types to help you make a succulent garden for yourself or to give as a gift. Please bring succulent cuttings you would like to share.Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.