Final answer:
The land used for corn farming in the USA has increased over the years, especially in states like North Dakota, due to factors like converging crop prices and higher yields per acre for corn compared to wheat.
Step-by-step explanation:
The land used for corn farming in the USA has seen significant changes over the years, particularly in the upper Midwest, which was traditionally known as "King Wheat." As of mid-2019, there has been a notable increase in corn production. In 1997, North Dakota planted 780,000 acres of corn, whereas recent figures suggest a substantial increase in land allocated to corn. A factor in this increase is converging prices that make it advantageous for farmers to plant more corn. It's important to note that corn yields more bushels per acre compared to wheat, contributing to the growth in corn acreage.