The steel plow was used to turn the top layer of soil, covering up the previous years plant matter and giving the farmer fresh black soil for the next years crop.
The steel plow was mainly used in the Midwest to break up the prarie sod to make it farmable. After its invention though it has been used everywhere a thick layer of soil needs to be turned. A very...
Yes it remains in use, but contour plowing and other conservation practices have ended the ravages of the dust bowl years. No one plows those unbroken mile long furrows anymore.