Cows and Climate Change

The globe’s recent wild weather, including the lowest arctic sea ice extent on record and this summer’s extraordinary drought, is gradually bringing the climate change conundrum back into our nation’s consciousness. Some of the press points to the livestock industry as a major contributor to the problem, and the number of stories denigrating the US beef industry seems to be gaining steam. I won’t argue that there’s nothing wrong with the beef industry, but it’s rare to see a story that does justice to the complex issues at hand.

As we move closer to 9 billion people, and as the impacts of climate change simultaneously hammer the globe’s food-producing capacity, it’s highly likely that feeding grain to livestock is going to become economically and socially untenable. And if this summer’s drought is any indication of what we have in store, this reality isn’t very far away.

But, that doesn’t mean that we have to stop eating meat. Ruminant animals like cattle, sheep, and goats aren’t physiologically designed to consume grain. Their digestive tracts contain huge fermentation vats called rumens that are full of cellulose-digesting microbes. Ruminant herbivores co-evolved with the grasslands and rangelands of the world, where biological decay of plant material seldom takes place due to environmental conditions that are too dry, cold, or hot for microbes to survive. But where do they survive? These organisms survive in the gut of the grazing herbivore. The high fiber plant material breaks down in the gut, and returns to the soil surface via dung and urine, where it is more readily incorporated back into the topsoil.

The presence of these animals in these grassland environments (which comprise over half of the earth’s land surface area) is critical to the cycling of carbon and minerals and the maintenance of functional hydrological processes and high levels of biodiversity. When these animals are removed, these environments tend to accumulate a net annual buildup of undecayed biomass which eventually becomes a liability to plant health and vigor. Species richness declines, soil surfaces tend to become capped, and there is an overall reduced level of ecosystem functionality.

The positive impacts of livestock can be enhanced if the animals are behaving the way nature intended, which in a pristine context always included pack hunting predators. The presence of predators keeps herbivores bunched and moving, and their movements tend to result in both heavy impact and grazing (for short periods), followed by long recovery periods that permit plants to recover their leaf area and root mass prior to the return of the migrating herds. This pattern of grazing and disturbance, followed by recovery, is the basic context under which soils, plants, and grazing animals co-evolved.

There are very few grasslands of the world still functioning in this pristine way, and the degradation that has resulted is massive—for this, poorly managed cattle and other livestock are largely responsible. Included in this degradation is a huge loss of soil organic matter, which is now in the atmosphere. Unlike the carbon dioxide and methane emitted by livestock in the process of digesting and respiring (which is simply part of the biospheric carbon cycle), this oxidation of soil organic matter is indeed a net emission that can be traced back to livestock, or more correctly, poor human management of livestock.  We’re still quantifying the extent of the damage and the science is inexact, but our current understanding tells us that between a quarter and half of our current atmospheric carbon overload is due to land use change, a huge component of which is the way human management of livestock has degraded the world’s grasslands.

So, we can use livestock to mimic the migratory behavior of the herds of old, and indeed this is one of the key ways that we are going to actually sequester the enormous load of carbon that needs to be pulled out of the atmosphere. The majority of land on which we’ll do this is too dry, steep, or rocky to use for cropping, so meat that is produced in this way does not consume any grain, and it does not supplant grain production. This land is dominated by native perennial plants as well, and when properly managed with livestock, we can reverse this flow of carbon, from the atmosphere and back into the soil, via the carbon sequestering capacity of the roots of these perennial grasses and forbs. The key point is that it’s not the cow that’s the problem, but the way the cow is managed that’s the problem. It’s not the tool, but how the tool is used.

This more holistic approach to ranching and grassland management was pioneered by a Zimbabwean, Allan Savory, beginning in the 1960s. It is now practiced by ranchers all over the world. Meat produced from livestock raised holistically, in the image of nature, is good for the planet, and indeed is a key element of mitigating the climate challenge.

In Cimarron, CO I’m Jim Howell for the Alternative Energy Resources Organization.  AERO has been building sustainable agriculture and energy solutions since 1974. Please join me in Lewistown during the last weekend in October for AERO’s 38th Annual Meeting.  Get meeting details and register online at

This commentary originally aired on Montana Public Radio on October 11, 2012.

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