The feasibility and profitability of short season corn and sorghum cropping systems on the Texas High Plains

Abstract

Studies of experimental cropping systems were conducted at the TAES-USDA Conservation and Production Research Field at Bushland, TX and at the North Plains Research Field near Etter, TX. The study at Bushland was fully irrigated using flood irrigation in level plots with raised borders. The study at Etter was conducted as limited irrigation using sprinkler irrigation equipped with a low energy precision application (LEPA) system. The four experimental cropping systems utilized a 98-day short season corn cultivar (SSC), a 100-day short season sorghum cultivar (SSS), and winter wheat grazed-grain (Wht Grz-Grn) and grain only. The cropping systems were evaluated in terms of attainable yields, irrigation water use, profitability, and feasibility. Conventional cropping systems of continuous full season corn (FSC), continuous full season sorghum (FSS), and continuous wheat grazed-grain and grain only were also included in the study. Compared to conventional cropping systems, the experimental cropping systems did not reduce irrigation, but profitability was increased. The rotation of SSC/Wht/SSS with wheat grazed or non-grazed, was consistently the most profitable rotation under full and limited irrigation. Profitability was obtained by increasing total revenue through improved yields of SSC in rotation with wheat and sorghum when compared to yields of SSC in continuous rotation, by obtaining higher market prices for early harvested SSC, and by realizing the opportunity to graze and obtain grain from wheat planted after SSC. Input costs were reduced by decreased fertilizer, insecticide, and irrigation applications and by reduced to no-tillage operations. Peak irrigation demands were spread more evenly throughout the year, and irrigation scheduling became less critical for optimum yields. Experimental rotations increased management and labor requirements. A greater diversity of machinery was also necessary. Timing of harvesting one crop and planting the next became critical in determining whether a rotation was profitable. The experimental rotation SSC/Wht Grz was not profitable and used the greatest amount of irrigation water. Conventional cropping systems of continuous FSS and continuous Wht Grz-Grn reduced irrigation compared to continuous FSC and all experimental rotations while maintaining profitability.