Thursday, August 13, 2009

Somebody check my math!

There was a recent post in an online forum which was making a case that vegetarianism is better from a carbon emissions standpoint than eating meat. It referenced one of many articles that complain (rightly) about the greenhouse gas emissions generated by feedlot meat. It spurred me to look for some data on grass-fed meat, by way of comparison. Here's part of what I wrote - including some rather surprising numbers:
I'm all for ending the practice of stuffing livestock with grains, and turning manure into sewage. Not to mention the health and disease considerations for the animals as well as the people! I'm also all for drastically reducing the amount of meat consumed.

But (you knew I was going to put one in here!) I just did some quick digging and came up with this*:
Conventional beef:         2.13 kg CO2 / 1 kg meat
Conventional corn: 0.15 kg CO2 / 1 kg corn
Cover crop + no-till corn: 0.06 kg CO2 / 1 kg corn
Grass fed beef: 0.02 kg CO2 / 1 kg meat

* based on numbers in these two links, converted to common units:

I picked corn because it was the easiest calorie dense crop I could find carbon numbers for. I couldn't find numbers for organic corn. I suspect it varies according to scale.

To be fair, I haven't added in electricity for the beef to keep it frozen or whatever. I guess it depends if you're keeping it all yourself for a year, or splitting it among many people, to be eaten relatively soon after butchering.

But even I found the numbers above surprising. (Maybe I should re-check my math.)

Is this a fair comparison? I don't know. Just throwing it out there. Is manure a methane disaster or a fantastic fertilizer? Depends how much you have and what you do with it I guess. Is growing perennials like grass and clover for grazing better for the soil than no-till corn and soy, or is that canceled out by cow farts? Did buffaloes fart? Can people grow veggies and beef using much less than the numbers stated in the referenced articles? (That I'm sure of. I'm trying to do both myself!)

But like I said, I'm all for getting rid of feedlots and cutting meat consumption in any case. And I salute vegetarians. It is a very effective approach.

My only point is that there's more than one workable answer, and the answers will vary based on many factors. There's no way in hell India is going to feed itself on pastured livestock. (I fear I could have stopped that sentence partway through.) Nor Japan. Nor New York or Los Angeles I suspect. But on our little 8+ acres, I'm pretty sure I can raise a cow on grass & hay for less fuel (and less money) than it would take to cover the whole property in annual crops.

(My dream is pastures with rows of mature nut trees in them....)
This line of inquiry was partly spurred by our recent purchase of a quarter of beef from the neighbor whose cattle are currently grazing on our property. He finishes his on grain, but I was thinking about how little fuel (and money) it would take for us to raise Meadow's (presumed) calf on pasture and hay alone. It couldn't take more than five gallons of fuel to cut hay for one bovine for one winter. And that's pasture I'd have to mow anyway! So what other expense would there be besides the butcher's bill? Water is abundant here. We wouldn't need any other feed. A few pennies worth of mineral block. And free fertilizer and mowing.

I bet we could beat that 0.02 / 1 ratio. Of course, if I was man enough to scythe and stack the hay, I could get to 0.00. But I'm not.


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At 8/14/2009 8:50 AM, OpenID helwen said...

Interesting numbers!

On food gathering the CO2 emissions will never quite be zero, because there's always the cost of gathering, food preparation, and/or storage. I think the closest you might get is having foodstuffs growing everywhere, year-round (so not in temperate climates) and being able to just grab something and eat it raw. Okay, I'm being a little silly but....

On food storage, there's always cost. Even if you hayed by hand, there's still the fuel needed to power _you_. One type of fuel may be more environmentally sound than another, but either way, fuel of some type is required, so I wouldn't worry too much about being "man enough". You guys are doing great!

Heather G

At 8/15/2009 8:01 AM, Blogger Wendy said...

Raising your own will never result in the extremely high carbon load that is created in factory farming.

I don't have the space for a cow, and I will never raise one, but I have plenty of room for chickens, rabbits, and maybe a goat. My neighbor next door, with his acre of land, doesn't have enough room for a cow, either, but he could raise a pig ... or two, and maybe I'd trade him some home-grown chicken or smoked rabbit for a couple of pounds of bacon. In places like India and China, outside of the cities, many folks are in the same situation as I am with just a small piece of land.

I will never believe that vegetarianism is *superior* to having a well-rounded and diverse diet - which includes animal products, and I think by having dialogues that vilify eating meat, we do ourselves a great disservice.

Yes! Factory farms are vile and should be outlawed, but that's not the only option for meat eaters, and indeed, my family no longer eats meat raised in that way. But we still eat meat - from our yard, and from local people who raise the animals on their farms.

Currently most of our grain crop is agri-farmed, which isn't so much better with regard to carbon emissions, and absent meat, most people have a diet that is very heavy in carbs/grains. If we all stopped eating meat, we'd need more grain. But grain doesn't grow well in all places, which means needing to truck it all over the world. And growing grain is pretty energy intensive.

The best option, in my opinion, is to localize one's diet and make it based on what can be easily grown/found in one's region. In my region, that will include meat, but not rice, or pineapple, or oranges.

At 11/02/2009 5:20 AM, OpenID onestraw said...


I think your numbers are very close, and pass my "common sense" test. My one challenge is that "no till" corn is very Round-Up intensive, and not sure if that number factors in the herbicide CO2 lifec ycle.

@ Helwen, I think not only can the C02 be zero - it can (and needs to be) negative. Pastured beef -ADDS- topsoil at least 500+ pounds of topsoil per acre, but more importantly add very significant amounts of organic matter (carbon) back into the soil already there. Raising the OG % by 1 sequesters 21 tons of carbon per acre. That gets you negative very quickly.

E4 - another issue regarding India or any other populace system. At sane meat intake levels you can raise meat animals in diverse polycultures with very close to no reduction in vegetable production per acre - in many cases it will add to it. With India's growing season, there is no reason that the cattle can't graze the millet and rye crops once early, and they can heavily graze the fields post harvest and all the cover crops. Because animals eat organic matter we can't (ruminants the stalks, chickens the insects) they make the system MORE productive not less.

CAFO's and feeding corn to ruminants (which makes them fart more to give us the scary methane numbers- buffalo fart less because they don't eat corn) are industrialized insanity.

Permaculture and Bio Intensive farming techniques that build soil are the single largest CO2 sequestration item out there - your 9 acres could sequester 180 tons for every 1% OG you add.

Thanks for the post E4


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