Final answer:
The United States has distinct agricultural zones like the Corn Belt, centered on corn and soybean production, and the Great Plains, famous for wheat and cattle. Climate, water availability, and soil fertility define these regions' agricultural focus, while socio-economic factors influence farming practices and crop choices over time.
Step-by-step explanation:
The agricultural focus of each region in the United States is heavily influenced by climate, water availability, and soil fertility, which have cultivated diverse agricultural zones tailored to the conditions of their respective climates. This has led to the emergence of notable regions such as the Corn Belt and the Great Plains, contributing significantly to the nation's agricultural output.
In the Corn Belt, primarily east of the 100th meridian and centered on states like Iowa, corn (maize) and soybeans dominate due to ample rain and fertile soil that was once tallgrass prairie. As one moves westward toward the Rocky Mountains, through the Midwest and the Great Plains, the climate becomes more arid, shifting the agricultural focus to cattle raising and grain farms, where irrigation is possible.
Over time, economic factors such as changes in crop prices have prompted shifts in what farmers plant. Cities like Chicago became instrumental in the agricultural economy as centers for processing and distribution of food products. However, the landscape is also changing, with agricultural land shrinking due to urban development and issues like market consolidation creating challenges for farmers.