Cargill heirs Whitney MacMillan and Cargill MacMillan Jr. are not only the richest Minnesotans, they're lapping the rest of the field.

Forbes magazine released its list of the 400 richest Americans this week, and the brothers came in at No. 42, with a net worth estimated at $7 billion each -- more than double from a year ago, thanks to booming business at Cargill Inc. and fertilizer producer Mosaic Co.

That's also almost double the net worth of the third-richest Minnesotan, Carl Pohlad, whose $3.6 billion puts him at No. 102 nationally. He moved up from No. 114 last year.

MacMillan and MacMillan Jr. moved up from last year's rank of 135. Mary Janet Cargill was at 163 on the list this year with $2.5 billion. She did not appear on the list last year.

The Cargill-MacMillan family owns about 90 percent of Minnetonka agribusiness giant Cargill, where revenue rose 36 percent and earnings 69 percent in its most recent fiscal year.

Cargill has a majority stake in Mosaic, which saw its stock price soar until the commodities market peaked in July.

The richest American is Microsoft founder Bill Gates, with $57 billion, followed by investment tycoon Warren Buffett, at $50 billion.

CASEY COMMON