When it comes to combating world hunger and boosting agriculture, Howard G. Buffett—son of the world-famous investing icon—is a strategist much like his father.

But while the elder Buffett is known for his flighty plays in the stock market, you might say Howard G.’s passions are more down to earth.

"Soil is any farmer's most valuable working capital," says Buffett, who spends most of his time managing the Howard G. Buffett Foundation, based in Decatur, Ill., and as an advocate for soil conservation. "Soil fertility has the single largest impact on production capacity."

Buffett was in Seattle recently to discuss the manifesto, 40 Chances: Finding Hope in a Hungry World he co-wrote with his son Howard W. Buffett. Both men are farmers, but they’re not strangers to corporate boardrooms. Warren Buffett has said he'd like Howard G., 58, currently a board member at Berkshire Hathaway, to succeed him as non-executive chairman.

In 2006, Warren Buffett challenged his son by asking him what he would do if he had the resources to do something great. Howard G., an advocate of habitat protection and biodiversity, focused on a fundamental issue: hunger and food security for the world's poorest billion people.

Buffett, who farms 1,500 acres in Illinois, notes the U.S. benefits from some of the best soils and most productive agricultural lands in the world—a fertility belt that covers most of the lower 48 states.

That means that when the U.S. maximizes the productivity of its agricultural land, it should be able to save fragile ecosystems elsewhere. 

But the opposite has occurred. For example, he notes, an unintended consequence of former president Jimmy Carter's grain embargo in l980 against the former Soviet Union was the opening up of world markets to Brazil and Argentina, resulting in the destruction of huge tracts of Amazon rainforest to make way for agriculture.

In fact, Buffett says, American farmers have the potential to increase yields dramatically. This may seem surprising since U.S. farmers have been consuming water far more quickly than it's being replaced, stressing the nation’s water supplies.

But Buffett, who contends U.S. industrial farm practices are no longer cutting edge (Brazil, with far less productive soil, can nearly match our land productivity), advocates a "brown revolution." By that, he means paying attention to soil quality and engaging in conservation techniques that are well known but that industrial farmers in the U.S. nevertheless have ignored: cover crops, crop rotations, reduced tillage and the like.