Daughter Joan Whitney Payson raced horses under the nom de course Manhasset Stable.

Greentree Stable horses won many important steeplechase and flat races throughout the United States.

Murphy stayed until the end of the 1930 Pimlico fall meeting, and was replaced by James G. Rowe, Jr.[2] Trained by Rowe, the Whitney stable's colt Twenty Grand earned the Eclipse Award for Horse of the Year in 1931 and was inducted into the National Museum of Racing and Hall of Fame in Saratoga Springs, New York in 1957.

[7] Greentree Stable also had polo ponies[8] and steeplechasers, one of which won the 1946 American Grand National.

After the deaths of John and Joan Whitney, their heirs sold the Kentucky property to its current owners, Gainesway Farm, in 1989.