DES MOINES, Iowa, Aug 14 (Reuters) - President George W. Bush on Wednesday urged corporate America to adopt old-fashioned farm values of "hard work and honesty" as hundreds of top CEOs swore by their financial results under a government order.

"We can't stand for corporate corruption to corrupt America," Bush said.

With the top brass of many of America's biggest companies meeting a deadline to certify their financial results, Bush used speeches in Iowa and Wisconsin to pound home his point that most corporate leaders are honest but that those who are not will be prosecuted.

Bush took off his jacket and rolled up his sleeves at the Iowa State Fair, speaking on a stage set on hay bales and surrounded by tractors and other heavy farm equipment gleaming under a hot summer sun.

He called on corporate America to follow "the good old-fashioned farm values" as a way to restore confidence among investors shaken by a series of corporate scandals that sent the stock market plummeting.

"I'm talking about values of hard work and honesty. I'm talking about telling the truth. I love the priorities of our farm families: Faith, family and telling the truth and being honest and upright, and corporate America needs to hear that signal."

He added, "I want to assure you something, we find somebody cooking the books, we find somebody not being open and honest, we find somebody trying to get ahead by sleight of hand, they will be prosecuted and they will be held to account."

Bush adopted a folksy Texas twang to talk to hundreds of fair attendees dressed in shorts and T-shirts, and referred to U.S. Trade Representative Bob Zoellick as "my man Zoellick, who's the trade guy" to talk up free trade.

HOG-CALLING CONTEST

"I was hopin' to get here in time for the chicken-calling contest, or the hog-calling contest," he said.

Interrupting his four-week Texas vacation for a two-day Midwestern road trip, Bush tested some of the themes for the fall campaign for November mid-term elections. He raised nearly $2 million for two Republican candidates -- $600,000 for Wisconsin Republican Gov. Scott McCallum's tough fight to hold his office, and $1.3 million for Des Moines lawyer Doug Gross' bid for governor of Iowa.

At an evening reception for Gross, Bush attacked the Democratic-controlled Senate's refusal to go along with his demands for a Department of Homeland Security.

Bush has threatened to veto the legislation establishing the 170,000-strong department unless managers have more flexibility over hiring and firing, which Democrats say would gut worker rights protections.

"If you look carefully at what they're doing, they're more interested in protecting their own political turf, and their own jurisdictions, than the American people. They want us to be hamstrung by a thick book of bureaucratic rules because they have been more interested in special interests," Bush said.

Speaking to a Milwaukee audience at the University of Wisconsin, Bush said the economy was in recession when he took office, then Sept. 11 hit, and then corporate scandals erupted that had "been in the making for a while."

A day after an economic forum in Waco, Texas, that mostly endorsed his proposals for restoring robust economic growth, Bush said the citizens he heard from there convinced him of the underlying strength of the economy.

But Sen. Joseph Lieberman, the Connecticut Democrat flirting with a 2004 election bid after narrowly losing the vice presidency in 2000 with Al Gore at the top of the ticket, ridiculed Bush's forum, saying, "it seemed a lot less like a summit than a valley."

Himself visiting the Iowa State Fair, Lieberman said he feared Bush "will lead us to a deeper valley of a double-dip recession because this economy is in trouble and this administration has had no economic growth strategy."

The president visits South Dakota on Thursday to hold a homeland security event near Mount Rushmore. Nampa-Reuters 0144 150802 WEB story ENDS (NAMPA 150148)