American Billy Davis has been keeping bees since the 1960s. He has followed the sharp drop in the number of honeybees across the country. Two years ago, he set up a non-profit group called the Sustainable Honeybee Program. It is developing stronger bees and teaching beekeepers how to strengthen their bee colonies.

　　Brenda Kiessling volunteers with Sustainable Honeybee Program.

　　"All the trees that you see came from a seed. That seed was produced by a flower that was pollinated by a bee. If we didn't have the bees, we wouldn't have the trees, we wouldn't have the flowers, we wouldn't have all the fruits and vegetables, or one-third of the food that humans need."

　　Brenda Kiessling is a retired doctor. As a girl, she was raised on a farm. That is when she started watching bees.

　　"They work as a family. They are very interesting. It's always different. Even if you have one colony of bees, when you come out to look at it, you have to 'read it' that day. It's not going to be the same, doing the exactly same thing as yesterday."

　　Experts say more than one-third of the honeybees are disappearing. Their disappearance could have resulted from a combination of things like climate change, parasites and chemicals used in agriculture.

　　Virginia beekeeper Billy Davis is working to help honeybees survive.

　　"We are our salvation, not chemical companies or the professors. They do a lot of research that's important, but when the rubber hits the road, it's going to be the beekeepers."

　　Americans are trying different ways to fight the loss of bees. They include using less chemicals and pesticides. More people are planting bushes and flowers that bees prefer.

　　The Sustainable Honeybee Program works with bees. The program operates a farm with more than 50 bee colonies. Alex McLellan is the group's chief operations officer.

　　"The ultimate goal here is to generate bees that are able to take care of themselves better. And we proved by not using chemicals here for the last seven or eight years, that it is possible to keep bees and to have them survive without the use of chemical intervention. And that's important."

　　One tactic to help bee populations stay healthy is "hygienic behavior," or the ability to identify and remove diseased bees from the colony. Brenda Kiessling says the beekeepers test for this by using liquid nitrogen.

　　"We freeze 100 cells. We come back in 24 hours and we test what percentage of the cells the workers have removed and gotten rid of. Queens which have a hygienic percentage of 95 or 100 percentage are excellent."

　　Alex McLellan says the group has breeding programs for producing queen bees and sharing them with local beekeepers. He says these 'hygienic honeybees' will be able to recognize threats to the colony, and take corrective action.

　　"We keep records on every single hive, and that compendium of records goes back quite a long time. From that we can look at the genetics and the survivability of all our hives. Prior to this year, I think we had a survivability of something over 90 percent, that's far higher than the average nationally."

　　Richard Whitlow is one of the more than 20 volunteers who work at the farm.

　　"Today we are inspecting the hives to make sure there is enough room for the queens to lay eggs and that they are starting to work on their storage for the winter. Egg laying is very important so that they can build the hive up, to have a thriving hive going into the winter."

　　Training volunteers is only the first step. The next steps are up to them, when they go home, to use what they learned and share with their neighbors.

　　I'm Marsha James.

　　VOA's Faiza Elmasry reported this story from Purcellville, Virginia. Marsha James adapted it for Learning English. George Grow was the editor.