Integrated crop-livestock systems in the Texas high plains: Productivity and water use

Sustainable irrigated agriculture in the Texas High Plains is threatened by declining aquifer levels. Two systems integrating field crops, forages, and stocker steers (Bos taurus) were evaluated (2004-2011) for productivity and irrigation use in a randomized block design with three blocks. the non-irrigated system (LOW) included native grasses and a rotation of cotton (Gossypium hirsutum L.) with annual warm-season grasses. Beginning in 2009, this system was buthered by adding a paddock of irrigated WW-B. Dahl old world bluestem [Bothriochloa bladhii (Retz) S.T. Blake] for grazing and seed production. the second system (MOD) was irrigated, including two paddocks of Tifton 85 bermudagrass [Cynodon dactylon (L.) Pers.] for grazing and hay and one paddock of old world bluestem for grazing and seed production. Irrigation use by LOW (0-49 mm yr^-1) and MOD systems (135-286 mm yr^-1) varied by year. the MOD system produced more forage than LOW (5966 vs. 2848 kg ha^-1) from 2009 to 2011, but was less efficient in irrigation water use (MOD: 114-349 and LOW: 339-907 kg forage produced cm^-1 irrigation). Steer gain ha^-1 was greater in MOD than LOW in all years. Yield and quality of cotton lint produced by LOW were good for the region. Both systems othered options for continuing agricultural production while improving management of soil and water resources, but optimal design for a given location will depend on water availability, conservation goals, and preferences of landowners and managers.