After briefly leaving the service, Hartzog returned as associate director in 1963 with the promise of succeeding Conrad Wirth in January 1964.

During his nine-year tenure, he enlarged the service's role in urban recreation,[2] historic preservation, interpretation, and environmental education.

Harzog pioneered what became known as the Washington Monument syndrome political tactic and closed all national parks two days a week.

"[3] Nixon fired Hartzog in December 1972, despite attempts by Secretary of the Interior Rogers Morton to talk the president out of his decision.

[4] Nixon opted to replace Hartzog with the White House head of travel arrangement Ron Walker, an "unqualified appointment" who openly admitted "that he did not know the difference between the National Park Service and the Boy Scouts.