Forage and Crop Residue Utilization in Corn and Beef Systems in the Midwest.

Historically, beef production systems in the Midwest USA have included spring and fall grazing of perennial cool-season grasses, summer grazing of warm-season perennial grasses, and winter grazing of corn (Zea mays L.) residues, with annual forages filling forage needs during various grazing periods. Despite regional reductions in livestock numbers as perennial grasslands are converted into row crops, opportunities to increase forage production and utilization are attainable using combinations of crop residues, perennial pastures, and annual forages as cover crops following grain production. Specifically, a cost-effective integrated crop-livestock system increases the grazing use of corn residue, in addition to supplemental feeding of distiller’s grains, while relying on perennial grass pastures. Common spring and fall grazed perennial grasses include smooth bromegrass (Bromus inermis L.), intermediate wheatgrass [Thinopyron intermedium (Host.) Barkworth & D.R. Dewey], and crested wheatgrass [Agropyron cristatum (L.) Gaertn.]. Multi-year farm trials have measured mean average daily gain (ADG) ranging from 0.82 to 1.3 kg hd^-1 d^-1 and producing 132 to 298 kg beef ha^-1, depending on forage species. Improved native, perennial, warm-season grasses that may also be used for bio-based energy sources, such as big bluestem (Andropogon gerardii Vitman.), can effectively replace smooth bromegrass for summer grazing, with similar rates of ADG. Strategic use of annual forages following wheat (Triticum aestivum L.), seed corn, corn silage, and high-moisture corn can produce 2,500 to 4,500 kg ha^-1 of high-quality fall forage. Though data is limited and variable, opportunities exist for providing additional spring grazing capacity using annual forages following grain harvest. The limited data for stewardship and ecosystem service goals suggest that grazing crop residues and cover crops does not have negative crop production, soil, or other environmental impacts. Diversifying crop-livestock systems with additional forage and bioenergy components may be more productive, sustainable, climate-resilient, and economically competitive than traditional cropping systems.