After the mid- 1930s, their numbers fell even more after the United States Forest Service and the U.S. Grazing Service (the predecessor to the BLM) began to remove feral horses from federal land.
After the mid- 1930s, their numbers fell even more drastically due to intervention by the U.S. government. The United States Forest Service and the U.S. Grazing Service (the predecessor to the BLM) began to remove feral horses from federal land.