Agricultural Land Use Change in the US Cotton Belt

Over 20% of the world’s cotton is produced in 17 southern states in the U.S., collectively known as the Cotton Belt.  Corn, grain sorghum, and peanuts are the major summer row crops competing with cotton for acreage in the region. Spatial differences in planted acreage of these crops is due to the variability in soil characteristics, irrigation water availability, and climatic conditions (mainly quantity and distribution of rainfall). However, there are temporal variations in agricultural land use in this region driven by ecological, and economic factors, and government policies. This study identified and quantified the factors influencing acreage distribution among the major crops in the region. Historic data on irrigated and dryland acreages of corn, cotton, grain sorghum, and peanuts by county from 1972 to 2015 was used to estimate the model. Regression equations were developed for each crop with its planted acreage as the dependent variable and year, lag acreage of that crop, the lag fiber:grain price ratio, and dummy variables for years each farm bill was in effect as explanatory variables. Iterative Seemingly Unrelated Regression (SUR) was used to simultaneously estimate these equations.  Separate models were used to estimate irrigated and dryland acreages.