cows in field

Methane Production in Grassfed Livestock

By Shannon Hayes, author of The Farmer and the Grill, and The Grassfed Gourmet Cookbook

Added March 13, 2009. (From the July, 2008 issue of NODPA News)

As debates about how to save the planet rage on, grass farmers are suddenly faced with an onslaught of questions about… believe it or not, cow burps and farts. Any of us who’ve sat quietly and milked our family cow can attest to the simple fact that, yes, grassfed cattle do belch quite a bit.

Enteric fermentation, the fermentation of forage in the rumen, is a natural part of the digestion process for ruminant animals such as cows, sheep, goats or buffalo. As Matthew Rales points out in his excellent article in the Spring 2008 journal Wise Traditions, rumen fermentation “is the process
that gives us fats like conjugated linoleic acid (CLA), and bone building nutrients like vitamin K”(1) Grassfed livestock belch more than factory-farmed animals because they have a higher amount of roughage in their diet, which comes from grasses, and less starch. Grainfed livestock have a higher percentage of starch, since much of their feed comes from corn (the production of which, as we know, is also responsible for a fair amount of greenhouse gas). The natural fermentation process is unnaturally suppressed in factory farmed livestock…but grainfed animals still burp and fart quite a bit. In addition, factory farming results in considerable carbon emissions owing to the fuel intensive production practices. Concentrated animal production can also cause very serious pollution problems.

Unfortunately, this natural process of emitting methane is causing a lot of folks to raise their arms in alarm, to forego their local grass-fed burgers, and to opt instead for a bowl of rice and veggies. Whoa! Stop right there….rice field methane emissions are a major source of atmospheric methane. Further, research is starting to indicate that vegetation is also a source of methane. Trees, too. On another note, those blessed wetlands that we regard as bastions of environmental health and wealth comprise 80% of all natural methane emissions (2). Still, human-made sources of methane exceed natural sources, and in the United States, the culprits are oil, coal and gas extraction, landfills, rice cultivation, biomass burning and, yes, ruminant livestock and waste treatment.

On her website, Jo Robinson reports on research that was conducted by Dr. Rita Schenck at the Institute for Environmental Research and Education which shows that, when we account for the carbon sequestration resulting from grazing animals (where well-managed pastures help to pull excess carbon out of the atmosphere), even with the increased enteric fermentation, the net result is still a reduction in greenhouse gases. Jo Robinson also reports on a study demonstrating that keeping ruminants on high quality pastures (using the management intensive grazing practices that most of our nation’s grassfarmers employ) can reduce ruminant methane emissions by as much as 20% (3). To learn more about how your consumption of local grassfed meats can help save the planet, check out the article titled Moving the World Toward Sustainability in the Green Money Journal, where grazing advocate and environmentalist Allan Savory shows us how we could stop global warming within 15 years using Holistic Management and management intensive grazing practices (4). Yes, despite their burps and farts, those grazing cattle, sheep and goats are still going to play a major role in saving the planet…so enjoy tonight’s cookout.

  1. Rales, Matthew. "An Inconvenient Cow: The Truth Behind the U.N. Assault on Ruminant Livestock." Wise Traditions, Vol. 9, no. 1, Spring 2008: 16-23.
  3. DeRamus, H. A., T. C. Clement, D. D. Giampola, and P. C. Dickison. “Methane Emissions of Beef Cattle on Forages: Efficiency of Grazing Management Systems.” J Environ Qual 32, no. 1 (2003): 269-77.
  4. Savory, Allan and Christopher Peck, “Moving Our World Towards Sustainability,” Green Money Journal, Spring 2008.

Shannon Hayes is the host of, and the author of The Farmer and the Grill and The Grassfed Gourmet. She holds a Ph.D. in sustainable agriculture and community development from Cornell University. Her family farm is Sap Bush Hollow, it is located in Upstate New York.