It won't bloom until summer, but already many eyes are on the California buckeye.
The tree's blossoms are poisonous to honey bees. Bees are attracted to them and forage on them, but the end result of the food provisions to the colony can be deformed larval development.
We've seen bee hives within a quarter of a mile of California buckeyes (Aesculus californica). And we've seen honey bees, native bees and other pollinators foraging on the blossoms.
At the recent UC Davis Pollinator Gardening Workshop hosted by the California Center for Urban Horticulture, Extension apiculturist Eric Mussen talked about the poisonous plants. (See PowerPoint presentations.) That led to one workshop participant wondering if the flowers of the California buckeye are poisonous to native bees. (Honey bees are not native; the European colonists brought them to the Jamestown colony, Virginia, in 1622).
Responded Mussen: "My guess: either the native bees that have been in the areas around California buckeye for a long, long time are not poisoned by the pollen or they have been selected (by death of the other genetic types) to avoid the pollen, that eons of natural selection have adapted them to coexist with California buckeye while using their resources."
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, shared: "We know California buckeye nectar and/or pollen is toxic to honey bees from years of experience with managed hives. Toxicity to native bees and other flower visitors is not so easily determined and to my knowledge has not been investigated. The fact that populations of native bees and butterflies visit California buckeye flowers and continue to persist in areas where the tree is a dominant part of the plant community tends to confirm what Extension apiculturist Eric Mussen says about them. Some good research projects here. So we still do not know if it is the nectar, pollen, or both that may be toxic to honey bees, much less to native flower visitors."
According to gardeningguides.com, the seeds in their raw state are poisonous to humans, but native Americans learned to get around that and use them for food. They pounded the seeds into flour and then cooked the mixture. "This tree had multiple cultural uses among California Indian tribes," the website says. "Many indigenous groups utilized buckeye seeds for food, often when other plant food sources were scarce. These tribes included the Costanoan, Salinan, Kitanemuk, Serrano, Wappo, Sierra Miwok, Coast Miwok, Chumash, Kawaiisu, Northern Maidu among others. The Pomo ate the seeds even when other important food plants were plentiful. The seeds are poisonous to humans in the raw state. Thus, the nuts were cracked open with a rock, the shells removed, the seeds pounded into flour, and their toxic saponins removed in a lengthy leaching process. The meal was subsequently cooked and eaten. There are many different methods for processing and cooking buckeye seeds for food, depending upon the tribe. The seeds have medicinal properties and were cut into pieces, mixed with water, and made into suppositories for hemorrhoids by the Costanoan and Kawaiisu. The Pomo cut bark from the base of the tree and made a poultice, which was laid on a snakebite. Young buckeye shoots were sometimes used as spindles or twirling sticks in fire-making kits of the Sierra Miwok, Northern Maidu, Wappo, Yahi and other tribes. Many tribes mashed buckeye nuts and poured the contents into quiet pools to stupefy or kill fish."
And, no wildlife will eat buckeye seeds except squirrels, such as the California ground squirrel (Citellus beecheyi).
Meanwhile, the poisonous blossoms continue to beckon the honey bees--and their colonies keep producing deformed bees.
And maybe give them a hug? Or two? Or three?
Some 3000 third-graders who participated in the annual Solano County Youth Ag Day on March 18 at the Solano County Fairgrounds made a beeline for the bugs at the Bohart Museum of Entomology's hands-on activity.
Future entomologists? Maybe.
The UC Davis-based insect museum, directed by Lynn Kimsey, provided just one of the activities on the Vallejo fairgrounds, where the youngsters visited cows, rabbits and chickens; watched sheep-herding dog demonstrations; participated in 4-H SET (science, engineering and technology) events, and went home knowing that chocolate milk doesn't come from brown cows.
The bugs? Oh, sure, some of the youngsters were initially a little squeamish and squirmish when they saw the Madagascar hissing cockroaches and walking sticks. But the "fear factor" soon vanished as they watched the insects crawl up their arms. The bugs tickled and the youngsters giggled.
Tabatha Yang, the Bohart Museum's education and outreach coordinator, said the youths really enjoyed the "hissers" and "stick insects" and learning more about them. Bohart museum volunteers Maia Lundy, Noah Crockette and Rachael Graham delighted in showing the bugs to the youngsters. A display of bee and butterfly specimens also drew "oohs" and "aahs."
The Bohart Museum, home of nearly eight million insect specimens, plus a live "petting zoo," traditionally provides an educational display at the Solano County Ag Day. The Solano County Fair Association hosts the annual event.
Next up in the Bohart Museum's lineup of educational activities: an open house from 1 to 3 p.m., Saturday, April 12 at its headquarters in Room 1124 of the Academic Surge Building, Crocker Lane. It's part of the campuswide Picnic Day.
If you like oranges, you can thank a honey bee.
Oranges are 90 percent dependent on honey bees for pollination.
Remember that week of freezing temperatures back in December? Yes, it affected California's $2 billion citrus industry. California Citrus Mutual estimated the freeze wiped out a quarter of the industry. And yes, expect to see the price of oranges and orange juice rise slightly.
Meanwhile, as spring descends in the Central Valley, the orange tree buds are slowly opening, much as they have since the Gold Rush Days when settlers began commercial production of oranges in California, then primarily in the Los Angeles area.
The sight of honey bees pollinating orange blossoms on a warm spring day is a sight to bee-hold.
Orange blossom special...
Indeed, to the untrained eye, the drone fly (Eristalis tenax) appears to be a bee. It's not; it's a fly.
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, calls the drone fly "The H Bee." That's because there's an "H" on its abdomen (see photo). Like all flies, however, it can be distinguished by one pair of wings and stubby antennae. The larva of the fly is a rat-tailed maggot that lives in drainage ditches, pooled manure piles and other polluted water. The adults are floral visitors. Pollinators.
The "H Bee" was among the pollinators that Thorp discussed at the UC Davis Pollinator Gardening Workshop, hosted March 6 by the California Center for Urban Horticulture.
Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology, switched from bee mimics (drone flies, syrphid flies and other insects) to talk about the "real" honey bees, Apis mellifera, which European colonists introduced to what is now the United States in 1622. "The honey bees' biggest problem today is malnourishment," he said. "A single honey bee colony requires an acre of bloom to meet its nutritional needs each day," he said.
The queen can lay 2000 eggs a day in peak season. "One cell of honey and one cell of pollen make one bee."
He urged the participants to "try to plant for late summer and fall bloom, when honey bees in California are having a hard time finding nectar and pollen resources."
Mussen cautioned that bees are subjected to toxic pollens and unnatural toxins (pesticides). Plants poisonous to bees include the California buckeye (Aesculus californica) death camas (Toxicoscordion venenosum), corn lily (Veratrum californicum) and some locoweeeds (Astragalus spp.)
Pesticides inside the hive (used to control varroa mites) and outside the hives can be fatal. However, he said, "any kind of pesticide a bee encounters--there's always a physiological change."
Following the morning-long speaker presentations, the participants visited the UC Davis Arboretum Teaching Nursery on Garrod Drive to check out and/or purchase Arboretum All-Stars and other plants, and they toured the Häagen-Dazs Honey Bee Haven, a half-acre bee friendly garden on Bee Biology Road that is under the wing of the UC Davis Department of Entomology and Nematology. The garden is located next to the Harry H. Laidlaw Jr. Honey Bee Research Facility.
Among those traveling the longest distance were Lake Tahoe UC Master Gardeners Lynne Broche and Bonnie Turnbull and Turnbull's 14-year-old daughter, Jessie Brown, a junior Master Gardener and an avid insect photographer.
The ceanothus blooming in the haven especially drew the attention of the workshop participants. Insects foraging in the ceanothus included two so-called "H bees"--the honey bee and its impostor, the H-marked drone fly.
It's a glorious day, the first day of spring, and what better time to mark the occasion by visiting the UC Davis Arboretum Teaching Nursery on Garrod Drive?
Mother Earth, a mosaic ceramic sculpture by talented Donna Billick of Davis, co-founder and co-director of the UC Davis Art/Science Fusion Program, overlooks a thriving garden populated with honey bees, butterflies, sweat bees, syrphid flies, and ladybugs.
Today we saw the mournful dusky-wing butterfly (Erynnis tristis), the first of the year. (How ironic a butterfly with such a sad name would be in the garden the first day of spring!) The more colorful painted ladies (Vanessa cardui) arrived earlier this month. (See the Central California butterfly monitoring site of Art Shapiro, distinguished professor of evolution and ecology at UC Davis for more information on butterflies and his research.)
The UC Davis Arboretum Teaching Nursery attracts scores of pollinators with such plants as ceanothus, salvia, California fuchsia, cut-leaf lilac, rosemary, bulbine and Spanish lavender.
Meanwhile, the officials at the teaching nursery are gearing up for their next public plant sales, set for three Saturdays: April 5, April 26 and May 17 from 9 a.m. to 1 p.m. Garden and irrigation experts will offer guidance for what to plant in your garden, including the Arboretum All-Stars, and offer advice on drought-related resources. A plant doctor clinic is also planned. (Members say 10 percent on plant sales.)
While you're browsing through the plants, don't overlook the pollinators! Indeed, they may just nudge you into buying a specific plant...