CAMERON, Texas – In the woods and rolling farmland of Central Texas, Clint Walker is breeding queen bees.

Stashed in nondescript boxes underneath a stand of trees, the bees could be easily missed.

But the queens are a lifeline for Walker and other commercial beekeepers, who are furiously trying to replenish their depleted hives.

Nationwide, commercial beekeepers have been hit hard over the past two years by a mysterious malady known as colony collapse disorder, which can seemingly wipe out hives overnight.

Honeybees are critical components of U.S. agriculture. Commercial beekeepers move their hives all over the country so a wide array of crops can be pollinated.

The bees add an estimated $15 billion in value to staples such as nuts, fruits and vegetables.

The California almond crop alone requires 1.3 million colonies of bees, roughly half of all honeybees in the U.S. By 2010, the almond crop is projected to need 1.5 million colonies.

If colony collapse disorder continues, beekeepers may not be able to meet demand.

That’s why Walker has switched his emphasis to breeding queen bees.

“I can’t raise enough queens; I turn down orders every day,” said Walker, a third-generation beekeeper whose own hives were devastated by colony collapse disorder in 2006.

One of his customers, James Lockhart of Las Animas, Colo., lost two-thirds of his hives last winter and is spending this year trying to rebuild his business. A year ago, he had 3,000 hives. By winter, he was down to 1,100.

Lockhart traveled to Texas over the winter to start rebuilding his colonies with the help of Walker’s queen bees.

He has now built his Colorado operation up to an estimated 2,400 hives.

“This summer will kind of hurt, but at least we’re on our way back,” Lockhart said. “If we don’t get hit again we should be OK.”

But the problem is growing worse nationally.

Beekeepers surveyed by the USDA Agricultural Research Service last winter reported a total loss of about 36.1 percent of their bee colonies, a jump of 13.5 percent from a year ago. In an average year, beekeepers would incur losses of between 5 percent and 10 percent.

Jeff Pettis, lead researcher at the service’s Bee Research Lab in Beltsville, Md., who conducted the survey, said there are no clear-cut answers.

“We don’t have one thing we can point to; we’re looking at a lot of combinations,” Pettis said. “It’s a combination of some primary stress on the colony that could include low-level pesticide exposure, poor nutrition, Varroa mites – or something else – that allow visitors to take advantage of a weakened host. Then we’re seeing a secondary invader actually kill the colony.”

Despite plenty of attention for several years, the problem is still growing.

“We’ve added a large number of commercial beekeepers who two years ago had no problems and this year have big problems,” Pettis said.

In Texas, the situation is a little more hopeful.

Last year, Texas honey production jumped 50 percent after a dramatic decline in 2006. The number of colonies producing honey was estimated at 105,000 in 2007, up from 82,000 the year before.

Paul Jackson, the state’s chief apiary inspector, said he’s heard fewer complaints this year but concedes that no one knows whether that will last.

Many commercial beekeepers in Texas ship their hives to three or more states annually, so it’s hard to know the condition of their colonies

“Everything looks pretty good right now,” Jackson said. “The big story is going to be this fall and winter. That’s when you tend to start having your losses. If beekeepers start having it again in back-to-back years, then you’re going to have real hurt.”

Walker, who is based in Rogers outside Temple, said most beekeepers remain wary.

“Any beekeeper that tells you they’ve got the situation figured out, they’re lying to you,” Walker said. “When you can’t keep a hive healthy, you’ve got problems.

“Everyone in the industry – we’re all wringing our hands – because the researchers can’t definitely give us an answer as to what’s causing the problem,” he said.

Walker, whose father started Walker Honey in 1938, returned to the family business in 1991 and still thinks he was right to come home.

He saw about 1,000 of his 2,000 hives affected by colony collapse disorder two years ago. This year, his bees have started to recover even as many fellow beekeepers have had problems.

He attributes his reversal in fortune to changing the way he uses his bees. Instead of taking hives to West Texas last summer, he kept them home. He plans to do the same thing again this year.

“We didn’t take any bees to managed row crops,” Walker said.

“We stayed out of managed agricultural production, except for almonds in California. Does that mean I’ve figured it out? No. But it means I’m going to continue doing what I’m doing.”