Greentree Stable, in Red Bank, New Jersey, was a major American thoroughbred horse racing stable and breeding farm established in 1914 by Payne Whitney of the Whitney family of New York City. Payne Whitney operated a horse farm and stable at Saratoga Springs, New York with his brother Harry Payne Whitney, who also had a large stable of horses. Greentree Stable had a training base at Aiken, South Carolina, while Greentree Farm in Lexington, Kentucky was established in 1925 as its breeding arm.