Farmers in northwestern Minnesota, U.S. are doing whatever they can to save expensive fuel during the fall harvest. One easy way to save fuel is to work the farm machines not excessively. Some new tractors are being used with GPS-guided, auto-steering mechanisms. The GPS steering system allows farmers to reduce overlapping, which wastes fuel and fertilizer. Without the auto-steering mechanism, 10 percent to 15 percent of acreage can be wastefully over-treated.