Bulls are judged with a "dummy" weight for four seconds to see how hard they will jump and twist to buck a rider. Bulls that do well can sell for up to $50,000.
The bucking bull has long been the embodiment of the American rodeo, and it takes just four seconds for a strong young bull to reap its owner as much as $50,000 in prize money.
Four seconds is how long each 1- or 2-year-old bull will wear a weight strapped to its back as the massive animal is judged on how high it kicks and how much it twists.
In the past 10 years, bucking bulls have become a major industry. The price of the best bloodlines can soar to $250,000, and competitions take place everywhere from Madison Square Garden to Wyoming.
Randy Shippy, owner of Shippy Rodeo Bulls in Colome, S.D., has seven bulls entered in a nearby regional competition. The competition is used to get young bulls ready for the contests with higher prizes.
The bulls kick and defy the brawny cowboys trying to place a blue box known as a "dummy" on their backs. By throwing off the box, the bull learns what it's like to throw weight.
It's supposed to get him ready to throw off a determined cowboy in a year or two, and Shippy says training bulls this way is only one new thing about the sport.
"We're trying to get animals that have good structure, good muscle, lots of kick, speed, intensity, you know, where they're really whipping," Shippy says.
Over the past 10 years, prize money has increased tenfold, industry officials say, because of the combination of more sponsors, greater competition and television contracts.
"People like coming to bull ridings — businesses know that," says Tony Weborg, the owner of the bull ring hosting the competition. "Bull riding draws good crowds, so they get a lot of bang for their buck."
Smaller competitions draw sponsorship from local business, but the national bucking bull competitions attract weightier sponsors: Ford, Stanley Tools and Evan Williams Bourbon. The industry has grown as major networks have signed on to air bucking bull events.
Matt Scharping, a Minnesota genetics company executive whose stiff collar looks a bit out of place in the dusty ring, gets publicity from a bull he co-owns with professional football player Jared Allen of the NFL's Minnesota Vikings.
The winnings support Allen's charity to help wounded soldiers.
"Since March we've raised $33,000 for the charity — the bull industry has," Scharping says.
The bucking bull industry has grown by 500 percent, according to the Professional Bucking Bull Association: Entry fees are up, and prizes are 10 times larger than they were 10 years ago.
Spectators and investors know they might not win big; in fact, they might lose what they've spent on the sport. But it's the challenge, they say, even the romance of literally rubbing shoulders with an enormous bull — an icon of the rodeo — that inspires them.
As the stakes keep growing, more people are getting into the game, in turn making the stakes grow even higher. The Professional Bull Riders Association says its world championships in Las Vegas this fall will pay the top winners $2 million.