The US Department of Agriculture (USDA) periodically releases data related to farmland in the US. This data can be analyzed to look at macroeconomic trends to determine how farmers are responding to world economic conditions. This chart shows the US farmland usage by crop from 1997-2017 for a few select crops.
Overall, the total amount of acreage in the US has steady declined over the past two decades. In 1997 there was ~955 million acres of farmland. That has steadily dropped to ~900 million acres in 2017.
The main reason for this is simply due to improvements in crop yields. Back in 1950 corn yields would average 40 bushels per acre. In present times corn yields average closer to 160 bushels per acre. Maintaining farmland hasn’t been as necessary due to improved yields that can feed much more people.
Another big reason for this is that farmland is disappearing due to rapidly expanding cities and towns. This so called urban sprawl has replaced agricultural land with land for commercial, industrial and residential development. Simply put, farmland has become less of a priority.
US Farmland Usage by Crop 1997-2017
Corn has reigned supreme in recent years due to the demand for corn based ethanol as a fuel alternative. However, the main reason why soybeans have surpassed corn as the most planted crop is due to Chinese demand. China is a huge importer of soybeans, soybean oil and soybean meal. In addition, their population has rapidly expanded since the disastrous Great Leap Forward, and food imports are required to maintain this.
In response, US production of the crop has skyrocket to meet the demand. It’s increased so much in fact that the US is currently the world largest producer of soybeans, though Brazil is close behind.
While wheat used to be the dominant crop in the US, it is much past its hay day. Despite a growing population, US wheat consumption has remained flat. In addition, wheat has not benefited nearly as much from the increased yields in recent years. Farmers have thus turned to other options for planting.
In the history books Cotton was King, especially in the South where it was a cash crop. But it has been a long time since cotton reigned supreme in the US. Low prices and the removal of a government subsidy have greatly reduced the number of cotton farmland in recent years.