Officials at Churchill Downs in Louisville, Ky., announced Friday that the purse for the 2011 Kentucky Oaks has been doubled to $1 million-guaranteed &ndash; making it the richest North American race for 3-year-old fillies &ndash; while also releasing the balance of the stakes schedule for the 2011 spring meet.\r\nAs usual, the $2 million Kentucky Derby will be the centerpiece of the meet. The 137th running of the Derby is set for May 7, when five other stakes will be run.\r\nThe Oaks is one of six stakes set for the May 6 card, when total stakes purses will reach $2 million for the first time. In 2010, the richest race for 3-year-old fillies was the $750,000 Cotillion at Parx Racing in Philadelphia.\r\nThe doubling of the Oaks purse comes in the same year that MI Developments, the chief rival of Churchill Downs Inc., began offering a $2.2 million bonus for races tied to the Black-Eyed Susan Stakes, which is set for May 20 at Pimlico, which is owned by MID.\r\nThe Oaks purse had been $500,000-added since 2000. Last year, when Blind Luck narrowly defeated Evening Jewel, the gross was $584,300. As recently as 1981, when Heavenly Cause won, the purse was less than six figures when grossing $79,300.\r\nIn all, 25 stakes worth more than $7.3 million are on the spring schedule. Churchill announced a number of changes, including purse decreases for the Stephen Foster, from $600,000 to $500,000, and the La Troienne, from $400,000 to $300,000. Three races had their purses increased, most notably the Alysheba, which doubles from $150,000 to $300,000.\r\nAlso, Churchill eliminated four stakes for this year: the Fleur de Lis, the Kentucky Juvenile, the Locust Grove, and the 3-year-old sprint race formerly known as the Matt Winn, which has been lengthened to 1 1/16 miles and now takes the place of the Northern Dancer on the June 18 Foster program.\r\nThe 39-day spring meet opens April 30, with the first of four night programs at the meet. Closing day is July 4.\r\nThe stakes schedule for the Churchill fall meet, which will include the Breeders&rsquo; Cup championships for the second straight year, will be announced at a later date.