I found a couple of items on steam tractors.
I could not find one that I had previously read about where a steam
winch or a tractor was placed at one end of a paddock and a steel cable
draws the plough across the paddock. I think they had one tractor at
each end of the paddock and between the two they pull the plough back
and forth as they move along the side of the paddock.
In the 1800s in the UK there were teams operating during the farming year.

http://en.wikipedia.org/wiki/Steam_tractor

http://www.youtube.com/watch?v=jPG5lIwyCfU