in the Garden Janet Mackey, [email protected], 3-23-11

My husband and I were beekeepers in Maryland for 3 years before we moved out here to California, and I find honey bees to be absolutely fascinating. I am going to focus on just 3 aspects of honey bees.  First, I’ll buzz through some honey basics  Then I’ll address 2 questions directly relevant to bees in this garden ̶ Since honey bees are native to Asia via Europe, how the heck did these little gals get to California? ̶ How is it that a non-native component of the ecosystem – the non-native – is so important to native plants?

Honey bee biology  The honey bee, Apis mellifera, is the only bee that makes honey. They are the quintessential social , living in hives of 20-30,000 bees with clearly defined division of labor. All of the work is done by female worker bees as nurse bees, mortuary bees, and field bees. The drones are produced in much smaller numbers and just have one purpose – fertilizing a virgin queen, should one appear in the neighborhood. The purpose of the hive is to protect the queen. When it is cold, they form a swarm around her to keep her at 92 degrees. If the hive is threatened, the bees will sting. But the bee dies when she stings, so she only stings if threatened, and she can only sting once. Emergency Rooms report that most people who show up with a “bee sting” have usually been stung by a yellow jacket, which is more aggressive and can sting multiple times.  Honey bees collect a large amount of nectar and year round to keep the hive supplied. Nectar is converted to honey and stored for food during bad weather. Pollen provides protein needed for raising young bees. You can see bees carrying pollen – balls of yellow or orange packed into pockets on their back legs. The color of the nectar and the presence of different types of pollen in the hive affect the color of the honey produced.  Without honey bees, fruit trees bear fewer fruits, berries are smaller and misshapen, and vine crops like squash and , bear small fruits that don’t fill out properly.  Several pests arrived in the U.S. in the 1980s and 90s that killed off large numbers of hives. The honey bee did not co-evolve with these pests and honey bees are just beginning to develop resistance. As a result of pressure from these alien pests, most of the feral honey bee colonies in the U.S. disappeared. Survival of the honey bee in the U.S. is probably due to the management of these pests by beekeepers. , the problem that has led to huge losses among commercial beekeeper in 2007 and 2008, is probably caused by a combination of exposure to very low levels of pesticides (that accumulates in the beeswax of the hive), stress associated with hives being moved from crop to crop, malnutrition (single crops during 6-week life; inadequate food or nutritive supplements during off- season), and disease. How did honey bees get to the garden?  English colonists brought beehives to the New World to supply honey for sweetening and to make mead and to provide beeswax for candles and waterproofing. The first record of bees being sent was in 1609. By 1621 the Virginia Company was regularly sending hives, and charts of early settlement in Massachusetts showed an apiary as early as 1640.  Bees swarm in the spring, if the hive is crowded, so very quickly honey bees brought to the colonies set up hives in the wilds of the east coast. The Eastern Woodland Indians prepared fields by girdling trees and burning their bark, but left the dead trees standing, and the hollow trees provided great locations for new hives for feral bees.  Since colonial times, many households kept bees for honey and beeswax. Understanding of the role honeybees played in plant wasn’t really understood until after WWII. It wasn’t until the 1950s that research about the benefit of active pollination of fruits started to transfer to practical application in the field.  Honey bees have been important to the industry in California. Almond trees are among the earliest flowering trees. There was great synergy between almond farmers who recognized that their crops benefitted from high levels of pollination when hives were brought in and beekeepers who had very weak hives at the end of winter when bees were at the end of their stored honey. Nearly 1 million honey bee colonies come to California every February for the 3 weeks of almond pollination. Honey from almond trees is not collected because it has a very unpleasant bitter taste.

How is it that a non-native insect is so important to native plants?  Honey bees can use nectar and pollen from any source – they didn’t need to co-evolve with a plant as long as they can access its resources. They need LOTS of nectar to feed the hive, so they look for large sources – such as flowering trees with thousands of flowers or fields of flowers.  UC Davis entomologist reported that more than 130 native California plants are visited by, and probably pollinated by, honey bees.  There are thousands of species of bees. There are 81 known species of bees in Berkeley, 1,600 species in California, and 4,000 in the U.S. Native bees of all sizes and shapes are critical as .  Differences between honey bees and native bees: Natives are mostly solitary, nest in the ground, don’t die after stinging, aren’t affected by some of the same pests and diseases since they don’t live together in hives with 20 – 30,000 sisters, and don’t make honey.  Unfortunately, native bee populations also are in decline. The loss of native bees is probably connected to alteration and loss of habitat. Industrialization of agriculture starting in the 1960s features large areas of monoculture without the weeds and wildflowers in hedgerows that are the natural habitat of wild pollinators. Without areas near nectar sources, the bees have disappeared. Widespread use of pesticides has also taken its toll on bee populations. (Beekeepers can work with farmers to have pesticides applied when the bees aren’t flying. Native bees don’t have this type of advocate.)  Honey bees most likely have not displaced or out-competed native bees. They aren’t aggressive, and there is plenty of nectar available. The problem native bees face is habitat loss. It may be that honey bees that pollinate native plants will be seen as a critical part of ensuring survival of native bee populations since the honey bees kept native plants pollinated in the absence of their natural pollinators. To sum up, honey bees are a great benefit to native plants, even if they didn’t evolve with them. Beekeepers have not domesticated the honey bee, they just help manage them. That management may have kept them from being decimated by disease and pest attacks and it certainly has been a boon to farmers who have added “pollination management” to optimize crop yields.

Apis mellifera – Salvia apiana, Salvia mellifera, Salvia ‘Bee’s Bliss’

Additional bits of information Magnitude and value of honey bee pollination services  In the United States alone, it is estimated that honeybees accomplish 1/4 of the pollination needed for all fruit produced for human consumption - an estimated $10 billion worth of work each year.  Nearly ¾ of the country’s commercial crop pollination by honey bees occurs in California  The greatest value of honey bee pollination is associated with the production of seeds. 20 vegetables (asparagus, carrots, celery, onions, radishes, and turnips) and many forage crops (, clovers, vetch) produce seed only when their flowers have been pollinated adequately.  500,000 colonies of bees are operated by 400 commercial and semi-commercial beekeepers in California. About 2,000 hobby beekeepers. Commercial beekeepers move their hives up to 6 times a year for crop pollination or to put the bees near natural forage.  California State Beekeepers Association organized in 1889  Almond Board of California was created in 1950 by the U.S. Congress to promote the relationship between honey bees and Almond crop – really can’t talk about in the U.S. without talking about almond pollination  Almond trees planted unsuccessfully by monks at California missions in mid-1700s, but weather was too cool and moist. During the 1800s, almonds were planted further inland and thrived in the San Joaquin and Sacramento areas.  Because the almond trees bloom so early (February), there aren’t many pollinators in California available to pollinate them. Almonds aren’t native here.  600,000 acres of almonds in CA in 2006; 700,000 acres in 2009  Cost per hive for almond pollination went from $10/hive in 1973 to $80 in 2006, $150 - $170 in 2009.  Cost for annual hive maintenance about $178/hive for off-season feeding (sugar water), nutrition supplements (pollen to encourage queen to start laying eggs earlier in the season to have enough bees for the almond flowering season), antibiotics and pesticides to keep the colony healthy.  With pollination service costs going up, almond growers are testing effectiveness of lower density of hives in the orchards; will have an impact on demand for hives  99% of almonds grown in U.S. and 80% of almonds grown worldwide come from California  In 2004 almond exports were double the value of California wine exports “Bee” came into use in the U.S. in the mid-1600s for a gathering of people with the purpose of combining work and fun, like a quilting bee. Bees and honey bees were an important part of colonial America.