Sustainable Systems Phase III

Over the past 100 years, the Texas High Plains grasslands evolved into a $20+ billion agricultural industry centered largely on cotton and finishing beef cattle in feedlots. Agriculture was made possible with fertile soils, cheap energy and fertilizers, and irrigation water from the Ogallala aquifer. Today, energy and related costs are escalating rapidly, and water in the Ogallala is declining at a rate of over 1 foot per year. Recharge is negligible, and water demand is expected to exceed supply within the next 10 to 20 years. With marginal profits, cotton acres are now declining and new industries, including dairies and ethanol plants are proliferating causing increased acres of corn, a crop that dramatically increases irrigation water demands. Sorghum could replace corn silage for the dairy industry and reduce water use. Moreover, with limited cropping of minimally irrigated, water-use efficient plants and a perennial grass grazing-based beef industry, integrated systems could be sustained indefinitely, but alternatives must be energy efficient and economically viable. Current trends cannot be continued. Our SARE-funded research, begun 15 years ago, showed that an irrigated, integrated, cotton-forage-beef stocker cattle system reduced irrigation water (24%) and nitrogen fertilizer (40%) with similar profitability to a cotton monoculture. Despite such promising results, these systems need refocusing to address emerging issues. Additional SARE-funded comparisons of a dryland, integrated cotton-native grass-stocker cattle system and a deficit-irrigated perennial grass-stocker cattle system remain relevant. With state funding, monitoring of 26 producer sites is further testing monocultures and integrated systems under irrigation and dryland conditions. With this historic and ongoing platform of replicated research and on-farm producer systems, we can generate information on energy use and energy economics so urgently needed to design efficient agricultural systems. Furthermore, by redesigning the original irrigated integrated systems to compare perennial forages for finishing beef cattle with a sorghum monoculture, we can further reduce water use and meet a growing market demand for forage-fed beef. Additionally, sorghum may flexibly meet needs for grazing, silage, or biofuels.

Specific objectives are:

To compare integrated crop and beef cattle (stocker and forage finishing) systems (both irrigated and dryland) and a forage sorghum monoculture for dependence on water (irrigation + precipitation) and energy, and impact on soil quality and erosion, and economic returns.
To determine energy use, energy efficiency, and energy economics of integrated systems and monocultures, representing both dryland and irrigated agriculture, using both new and long-term replicated field-scale systems and 26 on-farm producer managed systems
To translate results from Objectives 1 and 2 into practices incorporated in agriculture in the High Plains and other applicable ecosystems.

Systems will be compared for system and component water and energy use and efficiencies, plant and animal product quantity and quality, input requirements, economic profitability, and soil conservation and quality. A Farming Systems Research and Extension approach will be used to increase awareness, knowledge sharing, and adoption of appropriate technologies within the region and beyond using participatory methods with producers and industry as full partners to establish true Communities of Practice.