Using Spearmint And Lemongrass To Protect Bees From Mites That Threaten Hives

Amrine, not wearing any protective garb, picks up the small, metal firepot and blows more smoke through a nozzle into one of the stacked, wooden boxes placed near the tree line. The smoke is designed to keep the bees from attacking. It causes them to gorge themselves with honey – a survival instinct in case they must vacate the hive and recreate it elsewhere.

As bees continue swirling around his head, Amrine explains that the bees aren’t angry but confused from the smoke. He looks for the hook to attach the pollen trap.

“I was stung five times yesterday,” Amrine said, momentarily looking away from the hives. “On a bad day without my suit, I might get 50 to 100 stings. I probably get an average of 2,000 bee stings a year, but it doesn’t hurt me. I’m immune.”

He patiently screws the trap to the box, finishing it off with duct tape to seal any small holes. Located in an unassuming area next to the WVU Greenhouse, one might miss the importance of this research site.

But the honeybees are part of an ongoing research project at WVU that promises to put the University on the map in the world of apiculture (beekeeping) and aid the honeybees’ declining populations from what scientists are calling Colony Collapse Disorder (CCD).

The ongoing CCD problem escalated in November 2006 and seems to have spread to 27 states and Brazil, Canada and many parts of Europe.

This problem is not only important to beekeepers and to honey lovers; nearly one-third of the human diet comes from insect-pollinated plants, and the honeybee is responsible for 80 percent of that pollination, according to the U.S. Department of Agriculture.

A congressional study said honeybees add about $15 billion a year in value to the U.S. food supply. Among the crops to be affected are apples, nuts, avocados, soybeans, asparagus, broccoli, celery, squash, cucumbers, peaches, kiwi, cherries, blueberries, cranberries, strawberries, cantaloupe and other melons.

The shortage will potentially affect the beef industry too because the growth of alfalfa is dependent on pollination from the bees.

Although scientists around the country are investigating several possible causes, including pesticides, viruses, genetically modified crops and even cell phones, Amrine said he is certain that at least 70 percent of the CCD is caused by tiny mites, roughly the size of a sesame seed, and the pathogens they carry.

Amrine, an entomologist in WVU’s Davis College of Agriculture, Forestry and Consumer Sciences, and one of the nation’s foremost acarologists (mite specialist), bases that estimate on the research he has been doing on the bees since 1996.

Working in conjunction with Bob Noel, a beekeeper from western Maryland, they have come up with a three-part, all natural protocol for managing honeybees designed to kill or deter the maximum number of mites while having very little impact on the bee colony. The results are slated to be published in the International Journal of Acarology June 1.

The protocol involves first treating the hives with two essential oils: spearmint and lemon grass, (constituents of Honey B Healthy ^TM, a product now marketed by Noel).

“African people used lemon grass to manage honeybees for the last 60,000 years. They deserve the original credit for that. We mix it with spearmint, and it helps the bees resist the pathogens the mites carry by possibly boosting the bees’ immune systems,” said Amrine. “The underlying mechanisms of action of essential oils are poorly understood. There are various reports that state they are cytophylactic or that they actively stimulate the immune system to help ‘fight off’ pathogens. We treat declining honeybees with Honey B Healthy, and within 21 days, we see improvement.”

The next step is using a special wintergreen formula mixed with grease and shaped into patties. The grease is mixed with sugar, mineral salt, honey and wintergreen and placed inside the hives.

“The bees will eat it,” Amrine said. “It also combats pathogens and gives the honeybees an edge in improving their health. It doesn’t kill bacteria, but it stops their growth. Also the grease gets on the bees and makes it harder for the mites to try to hitch a ride.”

The final part of the protocol involves applying a formula of formic acid to the hive with soaked pads that trap the heat and cause the acid to evaporate. “Formic acid is present in the honey already in small amounts,” he said. “Heat from the brood causes the formic acid to evaporate and holds this vapor inside the nest. It kills 93 percent of the mites inside the hive in a one-day treatment.”

Amrine has worked with beekeepers across the country and in Europe. In 2006, he was named Researcher of the Year by Florida State Beekeepers for the help he gave some members of the group. “Every time we went to Florida, we got at least a 93 percent kill of mites,” Amrine said. “The beekeepers were amazed to see how well this worked. They’ve been fighting the mites and CCD for the past several years.”

Beekeepers, like any phase of agriculture, have to rely on the unpredictability of nature to make their living. One colony of bees is worth approximately $250, and pollination contracts with growers can earn a beekeeper as much as $250,000.

“Those beekeepers using our methods have a lot of bees and are doing quite well,” he added. “They are amazed to see how well this works.”

Amrine is one of the authors of what many feel is the defining mite guide, “Revised Keys to the World Genera of Eriophyoidea” (Acari: Prostigmata).