ABSTRACT
Medieval Innovations The Romans used a light plow for sandy soil, which early medieval farmers improved by adding an iron coulter, a vertical blade attached to the plowshare. They also attached a wooden moldboard at the back that moved soil away from the break, leav-
ing a furrow in which to plant seed. However, the light plow proved difficult to use on the heavier, more clay-laden soils of Central and Northern Europe.
