You can tell it's summer along Yolo County roads by the acres and acres of sunflower fields.

Looking like real-life Van Gogh paintings (Van Gogh painted them in vases, Mother Nature paints them in rows), the sunflower fields are nothing short of spectacular. With tousled heads rising toward the sun and golden locks nodding in the breeze, they stand their ground.

Sunflowers (Helianthus Annuus), native to North America, are one of our most recognizable flowers. They're a good food source, a designer's dream, and dugout tradition.

Earlier this year we fielded a call from a young man from southern California who wanted to know when the sunflowers would bloom in Yolo County.  He wanted to propose to his girlfriend in a sunflower field.

This is one agricultural crop that does not go unnoticed. Not by people, not by animals, not by birds, and especially not by honey bees and sunflower bees.   

The California Gold Rush (1848-1855) has nothing on honey bees.

Sometimes foraging honey bees are covered with their own kind of gold--pollen--or protein for their colonies.

We saw this honey bee dusted with gold from head to thorax to abdomen as she gathered pollen from blanket flowers (Gaillardia). Her flight plan seemed uncertain, as her load was heavy and her visibility, poor. She struggled to take off, but take off she did.

Speaking of the Gold Rush and honey bees, entomologists always associate the arrival of honey bees in California with the California Gold Rush. That's because honey bees were introduced to California in 1853, right in the middle of the Gold Rush.

Back then, the hills were covered with wildflowers where bees gathered nectar (carbohydrates) and pollen (protein). Today, however, scientists are worried about bee  malnutrition.

"Honey bee colonies need a mix of pollens every day to meet their nutritional needs," says Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology. "In fact, they should have a one-acre equivalent of blossoms available to them daily to meet their demands.  They can fly up to four miles from the hive--a 50-square mile area--to gather that food and water (and propolis, plant resin)."

A worried beekeeper recently asked him about the declining bee population and wondered why his own colonies were dwindling.  In addition to malnutrition, Mussen listed a few other possibilities:

Varroa mites – "They suck the blood from developing pupae and adult bees, shortening their lifespans.  They vector virus diseases, the easiest to see being deformed wing virus.  If you have adult bees around the colony with curly, undeveloped wings, then you have too many mites.  If you see mites on the bees when you look in the hive, that is too many mites."

Nosema ceranae and other diseases – "You need a microscope to see the spores of a Nosema infection.  Go to Randy Oliver’s webpage, Scientificbeekeeping.com, and look at the information on Nosema ceranae and spore counting."

Contact with toxic chemicals – "Since your bees can fly up to four miles away to forage, that also is the distance within which they can get into trouble with bee-toxic chemicals.  It is not likely that the organic farm is a source.  However, if there are other farms around, or if your neighbors (golf courses, shopping centers, parks, playgrounds, etc.) are having problems with sucking or chewing insects, they may have used one of the neonicotinoids on their shrubs or trees.  Turf and ornamental dosages are considerably higher than those used in commercial agriculture.  So, the amounts of toxins in nectar and pollens can be toxic to honey bees and other pollinators."

Mussen also acknowledged that California buckeye blossoms are toxic to bees. "This was a fairly dry spring," he said. "Not too many weeds and wildflowers were around when the California buckeye came into bloom.  Buckeye pollen is toxic to developing bee brood and to adult bees, if it gets to be their primary food source in the colony."

The problem could also be due to other issues as well, Mussen said.  "Maybe the queens did not mate with enough drones, or the queens got too hot or too cold during their journeys to your hives, etc."

"As beekeepers, it is up to you to stick your nose in the hive, look at everything and try to determine what may be going wrong.  If you are feeling way too new at this to have any idea of what is going on, then contact your local bee club--there is one in practically half of the California counties--and find someone to help access your problems."

And the pollen, that precious protein? "When beekeepers examine their hives, they should see a good supply of pollen with many colors," Mussen says.

It's the Fourth of July--a time to celebrate our nation's Independence Day.

Hurrah for the red, white and blue!

That also covers red, white and blue pollen collected by our honey bees.

If you look closely, you'll see their "patriotic" colors.

"The importance of pollen to the health and vigor of the honey bee colony cannot be overstated," writes emeritus entomology professor Norman Gary of the University of California, Davis, in his best-selling book, "Honey Bee Hobbyist, The Care and Keeping of Bees."

"Honey satisfies the bees' carbohydrate requirements, while all of the other nutrients---minerals, proteins, vitamins and fatty substances--are derived from pollen. Nurse bees consume large amounts of pollen, converting it into nutritious secretions that are fed to developing larvae. During an entire year, a typical bee colony gathers and consumes about 77 pounds of pollen."

Gary adds: "Pollen in the plant world is the equivalent of sperm in the animal world. Fertilization and growth of seeds depends upon the transfer of pollen from the male flower parts (anthers) to the receptive female parts (stigmas)."

Our honey bees are not native to America, but they've been here so long that many people think they are. European colonists brought them here to Jamestown Colony, Virginia, in 1622. Honey bees were established here before our forefathers signed the Declaration of Independence on July 4, 1776.

So, today, a time to celebrate the Fourth and a time to celebrate our honey bees, Apis mellifera.

When you visit the half-acre Häagen-Dazs Honey Bee Haven,  a bee friendly garden on Bee Biology Road at the University of California, Davis, you might just see a cuckoo bee.

The cuckoo bee (see below) is a male Triepeolus concavus, as identified by native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, who maintains an office in the adjacent Harry H. Laidlaw Jr. Honey Bee Research Facility.

Thorp has been monitoring the garden not only since it was planted--in the fall of 2009--but BEFORE it was planted, to collect the baseline data. To date, he's detected more than 80 species of bees, "and counting."

The cuckoo bee, nectaring on a blanket flower (Gaillardia), is just one of the species he's found in the garden.

The female cuckoo bee lays her eggs in the ground nests of other bees, including the sunflower bee, Svastra. Cuckoo bees are kleptoparasites, meaning that they steal the food stores provisioned by the host bee. Cuckoos lack pollen-collecting structures (scopa). So when the cuckoo bee eggs hatch, the larva will consume the pollen ball collected by the hosts, and kill and eat the host larvae.

Like human kleptomanias, they've found a way to make it in this world at the expense of others.

Thorp annually teaches at The Bee Course, described as a "workshop offered for conservation biologists, pollination ecologists and other biologists who want to gain greater knowledge of the systematics and biology of bees," and held at the Southwestern Research Station, Portal, Ariz. This year's dates are Aug. 25 to Sept. 4.  The workshop attracts people from all over the world, including dozens from the UC system.