The late Margaret Cargill, whose Anne Ray Charitable Trust backed last year’s PBS Fall Arts Festival with an $800,000 donation, was the most generous philanthropic donor in America in 2011, according to this year’s Philanthropy 50 list from the Chronicle of Philanthropy. The top 50 donors gave a total of $10.4 billion in 2011, up from $3.3 billion the previous year, according to the Chronicle study. Cargill’s $6 billion bequest created the surge; although she died in 2006, her foundations weren’t able to liquidate her assets until last year, the Chronicle noted. Here is the entire list, and information about how the 12th annual research project was conducted.