In 1959 , the Forest Service opened 42,500 acres ( 172 km ) to recreation .
In 1960 Congress passed the Multiple - Use -- Sustained Yield Act that , among other things , stressed timber production in the national forests .
In 1959 , the Forest Service opened 42,500 acres ( 172 km ) to recreation , and in 1960 Congress passed the Multiple - Use -- Sustained Yield Act that , among other things , stressed timber production in the national forests .