This is correct. It is called a shoe. Sometimes there is one on both ends of the cutter bar. The one near the pittman arm is the inside shoe and the other is the outside or land shoe.
To early farmers, any dividing of a field was "laying off a land." Laying off a smaller tract was done for a couple of reasons. At the rate of a few acres per day, it might me all a farmer could till before the planting or growing season passed. And, secondly, some progress could be seen in plowing a smaller tract; the psychological benefit of seeing an end to a task.
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