Federal farming gurus have spent nearly $56 million in recent years attending conferences around the world to talk about everything from bugs and bacteria to dirt and diversity.

In nearly two dozen cases, a single U.S. Department of Agriculture employee attended a conference at a cost to taxpayers of $10,000 or more, according to a Washington Examiner analysis of agency records. In one instance, the USDA spent nearly $57,000 for a conference attended by only one of its employees, according to agency disclosures that do not provide any explanation of the cost.

Nobody's minding the store.

Officials at USDA refused to explain spending on those or any other conferences they attended over the last four years.

USDA employees attended more than 100 overseas conferences, with China, Australia, Italy, France and Germany among the most popular destinations.

The agency website says an estimated 53,000 of its employees went to more than 1,100 conferences between the 2008 and 2011 fiscal years.

A review of data compiled by The Examiner from other sources, including USASpending.gov, found the department's posted figures may not accurately reflect all of its actual costs or how many federal employees were involved. (See the Examiner's interactive map of USDA conference locations in the map embedded above, and see the USDA's published spreadsheet of conference spending in the spreadsheet embedded below.)

The Examiner also found that hundreds of the globe-trotting bureaucrats attended events costing more per person than the now-infamous General Services Administration conference in Las Vegas two years ago.

The most costly event, according to the department's website, was a $1.2 million August 2009 gathering of 450 department employees at the Grand Hyatt Hotel in Washington, D.C., where the Obama administration's plans for the department were discussed.

Among the listed speakers was Van Jones, President Obama's controversial green jobs czar, who abruptly resigned two weeks after the rural development conference. The topic of his presentation was "transfer of wealth," according to the conference agenda.

Two months later, the agency spent another $700,000 to send more than 500 employees to a Dallas conference for training on a new farm bill.

In March 2010, USDA spent $1.2 million to send 600 staffers to a diversity management training conference for Asian, black and Hispanic employees in Kansas City.

Diversity meetings targeting minority employees account for more than a tenth of the agency's total spending on conferences, about $6.1 million.

The USDA went to 31 conferences that cost more than $10,000 per person, including nearly a dozen in foreign countries.

The agency sent 752 workers to 125 conferences that were more expensive per-person than the event that led to GSA's meltdown earlier this year, which cost about $3,000 per attendee.

The most expensive trip on a per-person basis was a July 2008 management conference in Washington, D.C., attended by a single USDA employee at a cost of $56,650.

Among the most unusual was a 2007 event in which the department sent a single employee to a two-week "China food and wine pairing" conference in New York City at a cost of $37,128.

The USDA online database gives no details for any conference beyond costs, dates and locations of the conferences, and the number of employees who attended.

Department officials did not respond to an Examiner request for additional information, even after the newspaper submitted specific written questions.

Unlike other federal departments and agencies, USDA must post its conference spending data online as a result of a provision Congress included in the 2008 farm bill in response to prior spending abuses.

"Nobody's minding the store," said Sen. Tom Coburn, R-Okla., a longtime critic of USDA travel costs. Coburn authored the disclosure provision in the 2008 farm bill.

"Across the federal government, too often it's seen as a perk that 'I ought to have this as part of my job, so I get to travel to Las Vegas or Hawaii or Florida,'" Coburn said.

Before anyone is sent to a conference, department officials should ensure the event is critical to the department's mission, the appropriate employees are attending, and video conferencing is not an available alternative, Coburn said.

But those criteria are not being met, he said.

Among the examples of conference spending not included on the USDA website is an August 2009 payment for a professional development conference at the Opryland Hotel in Nashville. The USDA Inspector General spent $463,940 for rooms at Opryland, according to USASpending.gov.

The Examiner also identified several costly conferences that occurred outside the timeframe in the official USDA database, which covers the department's October-September fiscal year. The most recent event listed on the USDA site was in June 2011.

Unreported conferences between June and December 2011 add $1.8 million to the overall cost of USDA gatherings. The five-year total balloons to $66 million when conferences for the first nine months of 2007 are added.

Mark Flatten is a member of the Washington Examiner special reporting team. He can be reached at mflatten@washingtonexaminer.com. Data editor Jennifer Peebles contributed to this story and can be reached at jpeebles@washingtonexaminer.com.