BOISE, Idaho – Billionaire J.R. Simplot, the spud king of America, died May 25 at his Boise home. He was 99.

Ada County Coroner Erwin Sonnenberg said Simplot apparently died of natural causes.

The quintessential Idaho farmer dominated the state’s business and political landscape for 70 years, and the company that bears his name remains a powerful force today – in Idaho and beyond.

His food production business expanded after World War II into freezing and canning, developing the product that would become the company’s mainstay: the frozen french fry.

Simplot struck a deal with McDonald’s Corp. founder Ray Kroc, and his fry business grew with Americans’ love for fast food.

In the mid-1970s, Simplot was charged with trying to manipulate Maine potato futures.

He was barred from commodities trading for six years and paid $50,000 in fines and an undisclosed amount to settle a lawsuit.

Simplot and his family were ranked at No. 80 on Forbes magazine’s 2006 list of richest Americans, with an estimated wealth of $3.2 billion.

His businesses, still family owned, manufacture agriculture, horticulture and turf fertilizers; animal feed and seeds; food products such as fruits, potatoes and other vegetables; and industrial chemicals and irrigation products.

In 1980, at age 71, Simplot took a gamble on the next generation of businessmen, giving Ward and Joe Parkinson $1 million for 40 percent of what would become computer chip maker Micron Technology Inc. Over the years, he pumped in $20 million more to help Micron build its first manufacturing plant and to stay afloat. Micron went on to become a major producer of DRAM memory chips, which are used to store information in personal computers.

Not a religious man – “I’m a fact man and if it don’t add up, I don’t buy it; I don’t believe in hocus pocus,” he said in a 1999 interview – Simplot credited his longevity to disdain for tobacco and alcohol.

He used to reward workers who quit smoking with $200 and once paid a couple to travel to Idaho schools exhibiting black lungs in bottles.

Born John Richard Simplot in Dubuque, Iowa, he was raised with five siblings on a homestead in Declo in south-central Idaho.

In 1923, he left home at age 14 with four $20 gold coins given to him by his mother. He paid $1 a day for room and board at Declo’s only hotel.

As a shrewd young businessman, Simplot bought interest-bearing scrip paid to teachers who were also boarding there for 50 cents on the dollar. He used it as collateral on a bank loan to buy 600 hogs at $1 each.

He spent the winter shooting wild horses, selling the hides and boiling the meat with potato scraps to feed the hogs.

When pork prices jumped the next year, he brought some rare fat hogs to market for a whopping $7,500.

That was Simplot’s stake for the potato business. He leased land and from an early partner learned to plant certified seed, not cull potatoes as was common then. Idaho’s dominance in potatoes grew with the innovation.

Simplot bought an early electric potato sorter and by 1940 had bought or built 33 potato warehouses along the rich Snake River plains from Idaho Falls to Vale, Ore.

A chance encounter with a Chicago businessman led Simplot into the onion-drying business in Caldwell in 1941. He made $500,000 the first year and soon was supplying much of the dried potatoes and vegetables consumed by U.S. troops during World War II.

The young man then started buying ranches, cattle and timberland. Taking notice of the wartime shortage of fertilizer, he bought phosphate reserves and built a fertilizer production plant at Pocatello.

Late into his life, the former McDonald’s board member drove his white Lincoln Town Car with “Mr. Spud” vanity plates to the fast-food chain for hash browns or french fries several times a week. More recently, he could be seen driving around Boise in a motorized cart.

In 2004, he donated his former home in the Boise Foothills to the state to be used as Idaho’s new governor’s mansion.

Like many captains of industry, Simplot had scrapes with the law.

In 1977, he and the J.R. Simplot Co. each paid $40,000 in penalties for failing to report income and claiming false deductions.

Looking back on the incident in the late 1990s, he essentially dismissed it, saying, “Basically, I’ve never done anything wrong that I know of.”