According to the National Agricultural Statistics Service (NASS), winter wheat acreage harvested in the Mid-South states of Arkansas, Louisiana, Mississippi, and Tennessee declined from 1.7 million in 2001 to 480,000 in 2005. In the fall of 2005, 840,000 acres of wheat were planted in the four states. If the 2001-2005 ratio of harvested to planted acreage of 81 percent holds, an estimated 680,000 million wheat acres will be harvested in the four states in 2006.
Most of the wheat in the Mid-South is doublecropped with soybeans.
Projected returns to monocrop soybean and wheat/soybean doublecrop systems using cost estimates and budgets for 2006 published by Mississippi State University (http://www.agecon.msstate.edu/Research/budgets.php ), the University of Arkansas (http://www.aragriculture.org/crops/soybeans/budgets/default.htm ), Louisiana State University (http://www.lsuagcenter.com/en/money_business/farm_business/budgets ), and the University of Tennessee (AE 06-12) are given in the accompanying table. Cost estimates do not include charges for land, management, and overhead. Estimated returns do not include government payments.
The cost estimates for the soybean monocrop systems are an average of Mississippi and Arkansas (minus fertilizer) budget figures, which are within 5 percent of each other. Tennessee and Louisiana cost estimates for nonirrigated monocrop soybeans are $152 and $147 per acre, respectively.
Projected soybean yields are those used in the Mississippi budgets, whereas projected doublecrop yields are those used in each state's budget.
Estimated returns to monocrop soybeans range from $37 per acre for nonirrigated May plantings to $126 per acre for irrigated early plantings. Estimated returns to doublecrop systems range from $0 per acre for the Arkansas nonirrigated system to $117 per acre for the Louisiana nonirrigated system.
Estimated returns for the Louisiana nonirrigated doublecrop system are much higher than those for the other states because the wheat budgets have no lime, potassium, phosphorus, herbicide, and fungicide inputs, and the projected soybean yield is greater.
Returns to doublecropping shown in the budgets of states other than Louisiana are not as high as those from the early-planted monocrop systems. Projected returns to irrigated systems are higher with monocrop soybeans.
Based on these estimated returns, it is likely that the decline in wheat acreage in the Mid-South is tied to the economics of monocropping soybeans compared to doublecropping. Returns to doublecropping equaling returns from the best soybean monocrop system are dependent on low wheat inputs and relatively high yields for both crops. Continuous low inputs to wheat likely will not sustain doublecropping as a viable enterprise.
Larry G. Heatherly is a retired USDA-ARS research agronomist and current crop consultant. e-mail [email protected] 
|Early-planted NI monocrop soybean||152||40||84|
|Early-planted IRR monocrop soybean||227||60||126|
|May-planted NI monocrop soybean||128||28||37|
|May-planted IRR monocrop soybean||216||50||78|
|Arkansas NI doublecrop wheat/soybean||315||50/25||0|
|Arkansas IRR doublecrop wheat/soybean||392||50/45||41|
|Louisiana NI doublecrop wheat/soybean||240||45/35||117|
|Mississippi NI doublecrop wheat/soybean||362||70/25||20|
|Mississippi IRR doublecrop wheat/soybean||410||70/45||90|
|Tennessee NI doublecrop wheat/soybean||330||55/30||32|
|*Average of Mississippi and Arkansas (minus fertilizer) cost estimates for monocrop soybeans, which were within 5% of each other. Individual states' estimated costs for doublecrop systems.|
|**Mississippi projected soybean yields for monocrop soybeans, and individual states' projected yields for doublecrop systems. 2001-2005 NASS average wheat yields for Arkansas, Louisiana, Mississippi, and Tennessee are 50.2, 45.3, 48.5, and 50.8 bushels per acre, respectively (four-state average of 49.5 bushels per acre).|