 Marshall's dream of permanent wilderness protection became a reality 25 years after his death when President Lyndon B. Johnson signed the Wilderness Act into law on September 3, 1964, in the Rose Garden of the White House.Written by Howard Zahniser—who died of a heart attack at age 58 four months before the bill was signed into law— the legislation authorized the United States Congress to set aside a total of 9 million acres in selected areas in the national forests, national parks, national wildlife refuges, and other federal lands as units to be kept permanently unchanged by humans.It also provided for more acreage to be designated as wilderness for preservation.