Greentree

Greentree is a estate in Manhasset, New York on Long Island. The estate was constructed for businessman Payne Whitney in 1904 and was owned by members of the Whitney family for much of the 20th century. It is currently owned by the Greentree Foundation, a philanthropic nonprofit organization.
History.
Payne Whitney purchased the estate for his bride, Helen Julia Hay, in 1904. As with other Gold Coast Mansions, the original estate was pieced together. The five family farms that were purchased to make up the new estate were the Mitchell, Ketchum, Brinkerhoff, Skidmore, and Schenck farms.
Later, John Hay Whitney and his second wife, Betsey, occupied the main house, where Mrs. Whitney remained in residence there until her death in 1998. Radio and TV talk show pioneers John Reagan "Tex" McCrary, and his wife, model and movie star Jinx Falkenburg, intermittently lived on the Jock Whitney estate with their sons from 1947 to 1977.
The estate was later divided, with gifts of land being made to several organizations.
The remaining 408 acres, including the family home, are run by the Greentree Foundation, as a conference center dedicated to international justice and human rights issues. The Greentree Foundation was founded in 1982 by Betsey Cushing Roosevelt Whitney, and has owned the property since 2000.
The estate has hosted the Manhasset negotiations, a round of talks between Morocco and the Polisario Front, August 10–12, 2007, as part of a set of UN-led meetings centering on the future of Western Sahara, among others.