Answer:
The wilderness act of 1964.
Step-by-step explanation:
In this act, written by Howard Zahniser of the Wilderness Society, it was created a legal definition of wilderness ("...the earth and the community of life are untramelled by man,...), and protected 9.1 million acres of land. These areas can have no comercial activity and any motorized travel, such as cars, motorcycles, etc., and applies to portions of lands in national forests, parks, and other public lands.