Exploring integrated crop–livestock systems in different ecoregions of the United States

Authors: SULC, R - The Ohio State University; Franzluebbers, Alan

Submitted to: European Journal of Agronomy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/15/2013
Publication Date: 5/22/2014
Citation: Sulc, R.M., Franzluebbers, A.J. 2014. Exploring integrated crop–livestock systems in different ecoregions of the United States. European Journal of Agronomy. 57:21-30.

Interpretive Summary: Integrated crop-livestock systems are a minority way of agriculture in the U.S., yet a diversity of such systems have been explored in different regions of the country. Integrated crop-livestock systems combine the agricultural activities of crop and livestock production to directly transfer the benefits of one system to another, while trying to avoid any negative impacts. Scientists from the USDA-Agricultural Research Service in Raleigh NC and the Ohio State University collaborated in a review of literature assessing the potential for integrated crop-livestock systems in the U.S. Grazing animals can consume cellulosic plant components, which can stimulate soil biological activity and enhance nutrient cycling. Crop production allows economically viable nutrients to be applied to land and carryover of nutrients can be captured by subsequent forage crops. Conservation tillage management of cropland preserves the beneficial accumulation of surface soil organic matter to help avoid potential animal trampling effects on soil compaction. Winter cover crops are gaining widespread acceptance in many regions of the U.S., and they can be effectively grazed by ruminant animals to increase productivity of land while preserving environmental quality. This review illustrates the broad applicability of integrated crop-livestock systems in the U.S., although certain environmental limitations are equally formidable. Should economic and environmental stresses in U.S. agriculture increase, these systems will become more palatable to producers to reduce risks.

Technical Abstract: Large-scale, energy-intensive, specialized agricultural production systems have predominated the landscape in North America for the past half century. Although highly productive and economically successful, there is increasing concern with unintended negative environmental impacts. Production systems integrating crops and livestock have potential for providing additional ecosystem services from agriculture by capturing positive ecological interactions and avoiding negative environmental outcomes, while sustaining profitability. A diversity of ecologically sound integrated crop-livestock systems have been and can be employed in different ecoregions: sod-based crop rotations, grazing of cover crops in cash crop rotations, grazing crop residues, and sod-intercropping. Improved technologies in conservation tillage, weed control, fertilization, and planting, as well as improved plant genetics offer opportunities to facilitate successful adoption of integrated systems. This paper explores the potential of integrated crop-livestock systems in achieving environmental stewardship and maintaining profitability under a diversity of ecological conditions in the United States.