Short answers, pulled from the story.
The Sumerian debate between the hoe and the plough took place in the third millennium before the Common Era, with the poem dating back to approximately 2500 BC. This literary artifact personified the instruments to argue over which was superior for the survival of civilization. The text suggests the plough was already a symbol of progress and power at that time.
The first type of plough used in ancient Mesopotamia was the ard, a simple scratch plough that cut a shallow furrow into the soil without turning it over. This early device dates back to the 6th millennium BC and was pulled by domesticated oxen. The ard was a bow-shaped tool with a pointed share that dragged through the topsoil to create a narrow trench suitable for cereal crops.
John Deere, an Illinois blacksmith, introduced the steel plough in 1837. Deere's polished steel mouldboard could cut through the sticky, non-sandy soils of the American Midwest, which had previously been considered unsuitable for farming. This innovation opened up vast tracts of land for cultivation and fueled the expansion of agriculture across the United States.
The mouldboard plough required four to eight oxen or horses to pull it, which led to the rise of the manorial system in Northern Europe by the 10th century AD. This necessity for cooperation meant that multiple households worked together to cultivate the land, fostering the prevalence of corporations in medieval Europe. The heavy plough also led to farming being seen as men's work due to the physical strength required to operate it.
The chisel plough loosens and aerates the soil while leaving crop residue on top to reduce the effects of soil compaction. This type of plough is considered more sustainable than the mouldboard plough because it maintains high surface residue levels and reduces the risk of wind and water erosion. It helps to break up ploughpan and hardpan without turning the soil over completely.