|Harold E. Gulvin. Farm Engines and Tractors. McGraw-Hill Book Co., Inc., 1953.|
According to Gulvin's book:
"In 1869 an Illinois farm paper reported what it called 'the first actual success in steam plowing in America.' The steam plow ran 23 min, stopped for 6 min for wood, ran 13 min, stopped 8 min for water, and ran 1 min. It plowed 2.63 acres in 72 min, using 6 of a gang of 13 plows. The crew consisted of a man and team to supply fuel and water, a fireman, two men to manage the plows, and one of the inventors. The year 1876 is generally considered the date when the steam tractor engine was first used in the United States."