Environmental impact of livestock production

At MISA, we prefer a nuanced discussion of the role of livestock in agriculture and the environment.
Here’s the very quick-and-dirty sketch of our thinking on this topic:
– The major water quality problems in surface waters that receive agricultural runoff are excess nitrates, excess phosphorus, fecal coliform bacteria, turbidity, and hypoxia.  All of these problems can be mitigated or even reversed by cropping systems that feature continuous living cover (CLC); which means use of cover crops in tandem with annual crops like corn and soybean; and use of perennial crops in the system.
– Carbon stored in soil is lost when tillage occurs for the planting of annual crops like corn and soybean.  No-till systems can mitigate that to some degree, but these are not fully adopted by farmers.
– Carbon dioxide can be pulled from the atmosphere by growing plants and stored as soil carbon in agricultural cropping systems that employ perennial crops.
– The most established and likely pathway for an increase in acreage of perennial crops is for those to be forage crops, and for those forage crops to be utilized by a grazing animal.  Well-managed grazing of perennial grasses and other perennial crops can produce a saleable livestock product for the farmer while simultaneously sequestering soil carbon and reducing or nearly stopping agricultural runoff into surface waters.
– Thus, if we look at the potential benefits of perennial ground cover as opposed to the annual row-cropping of corn and soybean in terms of reducing runoff; AND the benefit in soil carbon sequestration from shifting more ground from annual crops to perennial crops; AND we look at the economic reality that dictates that a farmer must have a product of value to consumers to sell; THEN, on balance, a system that includes grazing livestock under good grazing management and using perennial forage is preferable to a system that excludes livestock.  We also like cover crops for their soil health, prevention of runoff, and prevention of leaching benefits; and using cover crops as forage for grazing livestock can also speed the integration of cover crops into a farmer’s cropping system.

Production of grass-fed beef is one option for farmers, but not the only option that could lead to an increase in continuous living cover on the landscape.  Returning cattle to a greater number of farms and keeping cattle on pasture for a longer period of time before putting them in smaller-scale, more localized feedlots is another way.  Keeping cattle on pasture but supplementing them with grain for their entire lifetime would be yet another way to achieve some of the rapid livestock growth seen in feedlots without sacrificing the environmental benefits of perennials, while driving more acres into those perennials.  It’s not necessarily about changing everything all at once, but about shifting the percentage of acreage away from annual row crops and towards perennials.
Please refer to the Continuous Living Cover manual, which goes into greater detail on the points I raised above, and includes many useful references.  In particular, if you look at nothing else, look at the Introduction, Integrating Livestock, and Placement of Continuous Living Cover chapters; and the Farmer Profiles.
See what’s being done through the University of Minnesota’s Forever Green Initiative to develop new crops and cropping systems that can provide continuous living cover:
You might also read these two excellent essays from the Land Stewardship Project about the benefits of grazing livestock:
“Grazing as a Public Good”
“Cussing over Creeks and Cattle”
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