Early Corn Planting as a Water Conservation Strategy in the Southeastern USA

In the agricultural region of the Mississippi River Alluvial Plain of Arkansas and Mississippi, USA, known as the “Mississippi Delta,” corn is typically planted between March 15 and April 20 each year. As regional climate change continues to threaten agricultural productivity, the search for stabilized corn production becomes imperative. Even in this humid, subtropical climate, crops are often exposed to hot temperatures and drought in the summer months, which result in reduced yields at harvest. Conversely, corn planted earlier in the season may be susceptible to frost damage, so there is a risk-tradeoff annually debated by farmers. Recent research shows that planting earlier is associated with a higher probability of moderate harm to the crops while planting later increases the likelihood of severe harm to the crops. The purpose of this project is to determine the amount of water saved by planting earlier by analyzing irrigation requirements (based on temperature and precipitation data) during critical times in the corn-growth period for both early and late plantings. Results suggest that interannual variability is large, but early planting consistently results in decreased water use for irrigation, which reduces the use of valuable groundwater resources across the region.