Grass, beef, and climate change—it’s complicated

cattle on the neighbour's land--a shot from inside Caledonia-Elmsthorpe PFRA pasture

“Grasslands restoration has been treated as the most efficient method in achieving carbon restoration and CO2 mitigation."[1] From a paper produced by Agriculture and Agri-Food Canada’s scientists.

Given what is happening in Paris this week, with climate change experts and world leaders gathered to craft a plan on how we might keep global temperatures from rising more than two degrees C. in this century, I thought I would try to say something in this space about the role that grassland management could play in helping us meet that goal. I was inspired in part by what was missing from a discussion hosted by Anna Maria Tremonti on CBC Radio’s The Current a couple of days ago: listen here. 

After listening to the program, I set off bravely into the slippery terrain of Google land, looking for the latest research on grassland and climate change. Within minutes I had slid down a gopher hole leading to increasingly shrill arguments between those who believe cattle grazing is a net contributor to human-caused climate change and those who believe it has at least the potential to be a climate change mitigator. (Here are two pieces that will give you a sense of the debate’s polarity: one that claims beef production is all bad, and that grass-fed beef is the worst; and one that claims that grass-fed is good for the planet once you look at the whole chain of energy going into feed lot cattle. )

Backing my way out into the light of day, I had to remind myself that I was looking for information on grassland and climate change, not livestock rearing and climate change. But there is no way around the beef production issue. Eight thousand years into the agricultural revolution—now compounded by the more recent and carbon-intensive industrial and information revolutions--we can’t have a meaningful discussion on grassland without talking about the domestic animals that justify its economic life and prevent it from being converted to an alternative economic life—supporting say lentil crops or a subdivision of starter castles.

Cattle and other methane-producing ruminants have jumped, cloven hooves first, into the discussion of grassland and climate change because they are the primary tool for grassland management over much of the planet’s native grass regions. What a livestock producer does with his cattle or sheep on the land will determine the quality of the grass above and below ground, which in turn affects the amount of greenhouse emissions (both methane in farting and belching and the nitrous oxide in manure) the animals produce. More importantly, though, stocking rates and intervals between grazing are crucial factors in determining how much carbon any given pasture captures from or releases into the atmosphere.

Well-managed grassland has been shown to have great potential to store carbon. In 2010 the United Nations Food and Agriculture Organization declared that “… globally, the potential to sequester carbon by improving grassland practices or rehabilitating degraded grasslands is substantial – of the same order as that of agricultural and forestry sequestration.”[2] 

Though it has yet to yield any public policy, a few people at Ag Canada seem to know this as well—see the quote at the top of this post.

How much carbon can grassland store? In a balanced article on the health and environmental pros and cons of beef in The Washington Post, the author, Tamar Haspel, refers to the work of Jason Rowntree, an assistant professor at Michigan State University who specializes in grass-eating cattle. Rowntree claims that some researchers have managed to sequester three metric tons of carbon per hectare (the equivalent of 3.7 tons of carbon dioxide.)

That sounds promising, but the research was done under ideal conditions and in a system that manages for carbon. Other estimates that have looked at grassland carbon sequestration in a full spectrum of field conditions, land types, and management regimes have arrived at lower estimates per hectare. There is much work to be done here to determine how grassland management can achieve some simple, natural and affordable carbon capture—as opposed to the unproven, complicated, and expensive technology Saskatchewan is using to help pump more oil out of the ground. Let’s hope that there are range ecologists or climate scientists out there right now who are thinking about the potential of restored and well-managed grasslands to store carbon, and who are going to access climate change research funding from the federal government now that we have people in Parliament who are not afraid of science.

In the real world of grassland and livestock production, though, almost no one is managing for carbon. Instead, the increasingly global and consolidated beef market drives producers to manage for the standard agricultural values of maximizing yield and minimizing costs. (It needs to be said though that our best grassland stewards actively resist those pressures by listening to the wisdom of their ranching forbears—make sure you save some grass for next year.)

                                                                          

If we expect otherwise and want grassland management to include carbon sequestration in the mix, we are going to have to put a policy finger on the scales of the marketplace to reward best management practices. That means federal and provincial agriculture programs to help distribute the costs of climate-friendly livestock management among consumers and the public at large. We all benefit from optimal grassland management—whether it is to produce Sage Grouse or sequester carbon—and that makes it as much a public policy issue as forestry or fisheries management. Here’s where we need people with environmental economics background to devise policy that will not be unduly disruptive to the supply side (producers) of things.

Unfortunately, this may or may not be welcome news to ranch families who value their legendary independence and manage their rangeland very well with little interference from regulatory agencies. But the outside world is coming down every prairie trail these days with big ideas and expectations in tow. We have suddenly found ourselves in an age when every decision we make—as consumers and producers—is everyone’s business.

Welcome to the troubled Commonwealth of Planet Earth—where cows do fart and grass do grow.

 The cattle and beaver managing this grassland and its wetlands may be providing us with the cheapest way to store carbon

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Further reading for keeners:

Britain’s widely respected National Trust sponsored a study that cuts through all of the vested interests protecting the grass-fed and feedlot sides of beef production and came up with a report showing that “extensive” grass-fed has a definite climate change advantage over “intensive” feedlot beef. Here is a summary that seems wise to me:

“Our findings, based on modelled sequestration data, indicate that the GHG impact of extensive beef production is not as high as calculated by less complete models. This should be reassuring for less intensive farmers faced with the obligation to reduce GHG emissions – it is possible that extensive grassland may in fact be carbon neutral or positive. When the true benefits to ecosystem services and human health are included, extensive livestock production on grassland is reaffirmed as the best use of this resource to produce food for people. On the basis of the issues covered in this report, our stance on beef production is that we will maintain our wider view of sustainability, which embraces optimal agricultural production based on land capability, animal welfare, local food production, and the protection of ecosystem services. We will continue our commitment to GHG reduction by sharing expertise between farmers on carbon-friendly farming, and maintaining our commitment to protect existing carbon-rich soils wherever they occur on our land holding. We will also continue to press for more formal and robust market mechanisms that reward farmers for the wider ecosystem benefits – including reduced GHG production – that extensive, grass-fed beef clearly brings. We need to future-proof all our farming, and a dash for maximised beef production in the face of increasing population demands risks long-term damage to the farmed and wider environment. finding ways to make it pay for farmers to pursue extensive, grass-fed beef systems will become increasingly important.”

And here is a blog post from “Animal Welfare Approved,” which is not an anti-meat, vegetarian organization. It comes out cautiously in favour of grass-fed, but reducing beef consumption--

Here is a Huffington Post article on grass-fed beef and climate change. 

And, finally, the research referenced in CBC's The Current this week stating  that 
“the livestock sector is responsible for nearly 15 per cent of global emissions – similar to that produced by powering all the cars, trucks, planes, trains and ships in the world.” In their analysis, the authors of say that “Livestock production is the largest source of two of the most potent greenhouse gases, methane and nitrous oxide. Methane results from digestion in ruminant animals such as cows, sheep and goats. Nitrous oxide is produced from manure and from fertilizers used to grow feed crops. Large amounts of carbon dioxide are also produced as forests are converted for pasture or to grow feed crops.”

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[1] From a paper produced by Agriculture and Agri-Food Canada’s scientists, Xiaoyu Wang, A. J. VandenBygaart, and Brian C. McConkey. Rangeland Ecology & Management, 67(4):333-343.)

[2] Challenges and opportunities for carbon sequestration in grassland systems: A technical report on grassland management and climate change mitigation. 2010