The Wilderness Act of 1964 () was written by Howard Zahniser of The Wilderness Society. It created the legal definition of wilderness in the United States, and protected 9.1 million acres (37,000 km²) of federal land. The result of a long effort to protect federal wilderness and to create a formal mechanism for designating wilderness, the Wilderness Act was signed into law by President Lyndon B. Johnson on September 3, 1964 after over sixty drafts and eight years of work. The Wilderness Act is well known for its succinct and poetic definition of wilderness: "A wilderness, in contrast with those areas where man and his own works dominate the landscape, is hereby recognized as an area where the earth and its community of life are untrammeled by man, where man himself is a visitor who does not remain." – Howard Zahniser When Congress passed and President Lyndon B. Johnson signed the Wilderness Act on September 3, 1964, it created the National Wilderness Preservation System. The initial statutory wilderness areas, designated in the Act, comprised 9.1 million acres (37,000 km²) of national forest wilderness areas in the United States of America previously protected by administrative orders. The current amount of areas designated by the NWPS as wilderness totals 757 areas encompassing 109.5 million acres of federally owned land in 44 states and Puerto Rico (5% of the land in the United States). Background Throughout the 1950s and 1960s there were growing concerns about the rapidly growing population in America after World War II, a period known as a baby boom. Additionally, American transportation systems grew in size which made transportation easier and increased environmental concerns. A leading concern was that environmental degradation would have an impact on air and water quality, this was partly addressed by the initial passage of the Clean Air Act in 1963. The problem of American wilderness available still persisted even after attempts to regulate pollutants. Part of America's identity was its vast untamed wilderness that was untouched by humans, which had fallen to about 2.5% of the total land in America by the 1960s. Previous efforts to conserve the nature had yielded public land designations and protections such as the National Parks System, National Forests, and primitive areas. Unfortunately, many of these designations came short of providing the necessary protections needed to keep the land preserved for future generations. The shortcomings of previous protections was exclaimed