The real reason billionaire Gates just became the biggest owner of farmland in America. : Late last year, Eric O’Keefe was researching a mysterious recent purchase of 14,500 acres of prime Washington state farmland. His magazine, The Land Report, tracks major land transactions and produces an annual list of the 100 biggest US landowners. Sales of more than a thousand acres are “blue-moon events,” O’Keefe noted, so this one stood out. And Eastern Washington has some of the richest, most expensive farmland in the country. But the purchaser of record was a small, obscure company in Louisiana.