For thousands of years, farming ran on muscle — human or animal. Then came the steam engine, the steel plow, and the reaper, and suddenly the race was on to mechanize agriculture. This documentary traces that evolution, focusing on the fierce competition between John Deere, Ford, and International Harvester to build the first reliable all-purpose tractor. By 1929, the field had narrowed dramatically, but the machine we recognize today had finally emerged — and it would go on to transform farming forever. This free program is open to the public. It is approximately 56 minutes, not rated, and made possible through PBS.