On Feb. 1, 1905, the first national forest reserves were transferred out of the Department of Interior and placed under the oversight of the Department of Agriculture. The Transfer Act moved more than 63 million acres and 500 employees to USDA, where a corps of trained foresters were ready to begin the conservation and farming of America’s forests. Now, the U.S. Forest Service manages more than 193 million acres and has 35,000 employees.

Environmental groups have repeatedly called for an end to logging on public lands over the decades. But the forest service’s primary mission — preserving forests in order to maintain a sustainable supply of timber for harvesting — harkens back 100 years to its original structure under the Department of Agriculture.

“Beyond serving as places for recreation, our forests are also sources of paper products, building materials, chemicals, and many other resources that drive our economy,” President George Bush said in a proclamation Feb. 1 honoring the Forest Service’s centennial.

Gifford Pinchot, the chief forester in 1905, established the famous “greatest good” yardstick for managing the nation’s forests: “Where conflicting interests must be reconciled, the question will always be decided from the standpoint of the greatest good of the greatest number in the long run.”