This threshing machine is being operated with the power from a steam engine. There were very few other tractors at that time. This grain threshing is being done on the Olof Person Farm near Lake John, in South Dakota, USA. Through the license plate on the car, I managed to trace the year to 1912. This is a very good picture of an old-time threshing rig. The bundles were all being hauled with horses.
You can see by the basket size they had a good coffee break, usually one at mid-morning, then a heavy noon meal and lunch, coffee again in mid-afternoon. The lady with the lunch basket no doubt brought the person with the camera out to the field.
I think most of the people in the picture are from the Person family, any help identifying them would be appreciated. I zoomed in on two that I think might be Erik Grape and Charlie Wayrynen.