Just how important are honeybees to the human diet? Typically, according to the U.S. Department of Agriculture, these under-appreciated workers pollinate 80 percent of our flowering crops, which constitute one-third of everything we eat. Losing them could affect not only dietary staples such as apples, broccoli, strawberries, nuts, asparagus, blueberries and cucumbers, but may threaten our beef and dairy industries if alfalfa is not available for feed. One Cornell University study estimated that honeybees annually pollinate $14 billion worth of seeds and crops in the U.S. Essentially, if honeybees disappear, they could take most of our insect pollinated plants with them, potentially reducing mankind to little more than a water diet.
Bees are of inestimable value as agents of cross-pollination, and many plants are entirely dependent on particular kinds of bees for their reproduction (such as red clover, which is pollinated by the bumblebee, and many orchids). In many cases the use of insecticides for agricultural pest control has created the unwelcome side effect of killing the bees necessary for maintaining the crop. Such environmental stresses plus several species of parasitic mites devastated honeybee populations in the United States beginning in the 1980s, making it necessary for farmers to rent bees from keepers in order to get their crops pollinated and greatly affecting the pollination of plants in the wild. In recent years commercial honeybee hives have suffered from colony collapse disorder, which, for unknown reasons, left many bee boxes empty of bees after overwintering. Bee venom has also been found to have medicinal properties, used for treating arthritis, multiple sclerosis and even fibromyalgia, and more recently to treat sexual dysfunction, cancer, epilepsy and depression.
Pollination is transfer of pollen from the anther (the male part of the flower) to the stigma (the female part of the flower). Some plants can pollinate themselves: in this case, the pollen passes from the anther to the stigma inside the same flower, and this is called self-pollination. Other plants need pollen to be transferred between different flowers or different individuals of the plant. This is cross-pollination. Many plants can be pollinated both ways. Plants can be pollinated by wind or animals.
Flowers pollinated by bees most often bloom in daytime, and can be different colors (though seldom red). The scent of daytime, bee-pollinated flowers tends to be less strong than that of night-pollinated flowers, which are often pollinated by bats or moths.
Honeybee-pollinated flowers have nectar tubes no more than two centimeters long. They have nectar guides (patterns to direct the bee towards the nectar) and often a landing place for bees. Bees are especially attracted to white, blue and yellow flowers. Plants pollinated by insects are called "entomophilous," and insects are generally the most important pollinators. Usually a honeybee can visit between 50 to 1,000 flowers in one trip, which takes between 30 minutes to four hours. Without pollen, the young nurse bees cannot produce bee milk or royal jelly to feed the queen and colony. If no pollen is available to the colony, egg laying by the queen will stop.
Humans' intense agricultural practices have greatly affected the pollination practices of bees in the U.S. The increased use of pesticides, the reduction in the number of wild colonies and the increased value of both bees and pollinated crops have all added to the importance of protecting bees. Furthermore, many homeowners believe dandelions and clover are weeds, that lawns should be only grass to be mowed down regularly, and that everything but the grass should be highly treated with pesticides. This makes a hostile environment for bees, butterflies and other pollinators. Many bee poisoning problems could be prevented by better communication and cooperation among the grower, pesticide applicator and the beekeeper.
Maria Boland originally wrote this story for MNN State Reports.