Climate Change and Grass-fed Beef

I have been passionate about the intersection of agriculture, energy and waste for a long time. The environmental issues associated with industrial agriculture – and meat in particular – are intricately linked to climate change, as agriculture contributes roughly 10% of the nation’s greenhouse gas emissions, and as much as 20% of the world’s greenhouse gas emissions.  The bulk of these emissions are from large-scale production of corn & soybeans, most of which is used to feed animals kept in confinement feedlots. 

There is a better way!

But replacing some of the meat in your diet with tofu or other soy products is probably not it. Soy has become virtually as ubiquitous in our diet as corn has over the last several decades. Beyond your own health are the associated environmental issues: the synthetic fertilizer and diesel fuel required for industrial scale corn and soybean production release carbon at a rate of approximately 1,000 pounds per acre, not to mention the emissions associated with trucking these commodities around the world. Perennial grasslands, on the other hand, actually store carbon at roughly the same rate: 1,000 pounds per acre. 

So for example, one of the 350-acre farms with which we work in Vermont is actually a net carbon sink of roughly 175 tons annually. For comparison, the average American home (heating, cooling, cooking, electricity, etc.) is responsible for about 13 tons of carbon emissions each year. So just one of our partner farms can offset the greenhouse gas impact of more than a dozen homes!

But don’t confuse the equation by buying from farms in Missouri or New Zealand. Folks are doing things right, right here in New England! Our little diesel truck often gets over 20 MPG, and it now feeds hundreds of families in the Boston area. 

Join us, and help us to grow our partner farms to convert more acreage to perennial pastures – and capture even more carbon in the soil!


  • Daniel says:

    Hey Charley, thanks for the post – do you mind sharing some more details about what "stores carbon at 1,000 pounds per acre" means (stored in the soil or in biomass, is that rate really constant, etc), and some more details about how the farm is a carbon sink? How do you treat methane in this analysis?

    Thanks so much, this is a topic I think about a lot, and getting lifecycle GHG impact analyses like these can be tricky


  • Charley Cummings says:

    Daniel thanks for the note…

    On the 1,000 lbs per acre, this is an estimate of carbon stored in the soil & biomass based on the results of converting cultivated land to intensively grazed perennial grasslands. There are a couple different sources for this estimate, but here is one:

    I am really just holding methane constant in the example. As you probably know, although methane is a more potent greenhouse gas, it is also less of a stock pollutant in the sense that it’s impact does not last as long as carbon dioxide. So although it’s important to consider, it is really comparing apples to oranges and I wanted to address carbon dioxide alone.

    On that note you may have seen studies (generally sponsored by the beef industry or affiliates) that suggest grass-fed beef emits more methane than corn fed beef. Most of these studies seem to ignore the fact that this is generally simply a result of grass-fed animals taking a longer time to mature (24+ months vs. 18 months). They also don’t consider carbon dioxide emissions associated with growing or transporting the corn feedstock for these animals. In other words, a study that says "grass-fed beef has more methane emissions, ergo, the climate impact is worse"… is arguably like saying "when I drive my Hummer I fart less than when I drive my Prius, so the methane emissions are lower in the Hummer." Well technically that is probably true, but that is a pretty bizarre way to frame the question…

    Anyhow happy to continue the conversation if you like, shoot me an email anytime at charley at

  • daniel says:

    Oh and we have to be careful about the food-miles argument too 🙂 Usually emissions at the farm dominate transportation emissions (for example a good review on lamb putting transportation at 5% of total lifecycle GHG impact for lamb shipped from NZ to the UK). Turns out that big centralized shipping by barge, rail, and 18 wheeler is remarkably efficient – pickup trucks typically get about 25-30 ton-miles/gallon (can transport 1 ton of stuff 25-30 miles on a gallon of gas), but 18 wheelers can get 180-190 ton-miles/gallon, trains in the US often get 400+ ton-miles/gallon, and large ocean freight can easily go in the range 750-1000 t-m/g; and modern refrigeration for meat, etc is also amazingly good, usually only contributing only a fraction of that 5% for total transport, even including the impacts of leaked refrigerants (see: and and first link for refrigeration). So shipping a long way isn’t necessarily a bad thing if the mode of transit is 10-40x more efficient than a little pickup truck.

    Of course, there are still tons of reasons to buy local (it’s definitely my preference), but we should be careful about figuring out what the environmental impacts of that really are, and acknowledge that in some circumstance it can be more environmentally benign to grow in a centralized way and ship (especially for plants and animals that thrive best in a certain region of the world – can use much less land and emit less CO2 producing there and shipping than trying to grow locally in lots of places). Doesn’t mean we have to choose centralized, just be clear-eyed about the impacts and trade-offs.

    Thoughts/comments/rebuttals? Thanks again,

  • Charley Cummings says:

    Yes, agreed on both counts – transporting goods by train is quite clearly more efficient than individual pickup trucks on a per ton-mile basis, and it does make sense to grow products in regions of the country to which they are best suited from a climate, soil and geographic perspective. And in that respect, by far the highest and best use of New England’s agricultural land is in perennial pastures, given our climate, soil content, annual rainfall etc. So while I’m not arguing here about the merits of growing tomatoes in New England vs. in California’s Central Valley (although they sure do taste better right off the vine!), I would certainly argue that 1lb of corn fed beef from Missouri has a substantially higher climate impact than 1lb of our grass-fed beef from Vermont, New Hampshire or Mass. And it’s generally a result of mining, refining and applying synthetic chemicals to grow the feedstock rather than transporting the end product. Don’t forget the implications of the back end of the industrial process either – managing the manure filled lagoon required at the feedlot. We’ll try to put together the quantitative case to prove this out, as it’s a critical question.

    On the qualitative side, as you allude to, we also believe there is a tremendous benefit to reinvigorating local agricultural communities, and reconnecting consumers with their food, most important of which is arguably a shared understanding of the true health, environmental and social implications of the food we eat.

    We could debate about data all day… and it seems like we share a data-driven approach. The challenge is that generally folks are entrenched in their beliefs, and are often driven more by emotion than science. And truthfully anyone can find data and manipulate it (in a completely honest and genuine manner) to illustrate any point they like – the methane emissions of beef is a good example of this. In this context, emotionally something just feels right about buying from people you know, in your own foodshed, who are raising animals in a manner that is consistent with our moral compass, in the environments that they have evolved to thrive in, engaging in the activities that they are evolved to perform. Holistically, this simply cannot be more environmentally damaging in any sense of the word that than industrial alternative. That being said, I’ll continue to debate on the quantitative data 🙂