Economic Evaluation of Texas High Plains Cotton Irrigated by LEPA and Subsurface Drip

As water supplies and availability continue to decline in Texas, it is imperative to adopt the most efficient irrigation systems and management techniques. The focus of this study was to optimize irrigation management techniques for low energy precision application (LEPA) irrigation and subsurface drip irrigation (SDI), and compare resulting cotton lint yields and profitability of these irrigation approaches. Four-year average LEPA and SDI cotton lint yields were l046 lb/ac and 1171 lb/ac, respectively, using only 7.3-in or less of seasonal irrigation water per year. Differences in LEPA and SDI yields are attributed to higher water losses by the LEPA system due to soil surface evaporation. Economic analysis of Texas High Plains cotton production showed that LEPA resulted in higher net returns to management and risk than SDI as irrigation capacity increased above the 0.1 in/d level. However, SDI treatments resulted in net returns of over $80/ac and may be an acceptable alternative where LEPA installation costs are greater than $333/ac, physical constraints prevent the use of LEPA, or SDI installation costs are lower than $800/ac.