A 160-acre research validation farm was established in 1990 as a joint project of the Texas Agricultural Experiment Station, Texas Agricultural Extension Service, and Lamesa Cotton Growers. This farm provides an opportunity to evaluate conservation tillage cropping systems under both dryland and irrigated conditions. The farm is equipped with a low-energy precision application (LEPA) center pivot for high-frequency deficit irrigation. In 1993, irrigated cotton yields ranged from 737 to 1048 lb lint/A. Minimum tillage and conservation tillage systems produced higher cotton yields than the conventional tillage system. Net returns from all conservation tillage systems were higher than with conventional tillage. Highest net returns for irrigated cotton were achieved with a minimum tillage, continuous cotton system. Dryland cotton yields ranged from 214 to 553 lb/A, with highest yield produced with the wheat-cotton conservation tillage rotation system. Highest net returns for dryland cotton were achieved with wheat-cotton conservation tillage system. LEPA irrigation increased cotton yields an average 18% compared to conventional spray application.