Three reasons for the increasing demand for the production of wheat in the nineteenth century:
1.Increase in population from the late nineteenth century onwards which automatically gave a boost to the demand for wheat production to meet the needs of this rising population.The urban population in US was growing and export market was becoming bigger.
2.New technology substantially enhanced productivity in the 19th century, as sowing with drills replaced broadcasting, cradles took the place of sickles, and the cradles in turn were replaced by reapers and binders. Steam-powered threshing machines came into vogue.
3.The Russian supplies of whet were stopped and U.S became the sole wheat supplier. The spread of railways made it easier to export wheat to European countries.