A truly sustainable agriculture will involve animals, in order to complete the nutrient cycle, and those animals are going to be killed and eaten.
I was planning on addressing this point after getting to the point where he makes it in The Omnivore’s Dilemma, but this seems to be another good occasion for doing so.
I should begin by saying that I’m not an ecologist. I’m not going to claim to know definitively whether Pollan is right or wrong. However, he doesn’t provide evidence, so I’ll write a little bit about why I’m not convinced. If you know more than I do, I’d be interested to hear about it.
First of all, there are a number of successful examples of veganic (or vegan organic) farms, which keep no domesticated animals and use no animal inputs. Instead of animal manure, these farms use plant-based fertilizers, such as mulches and compost. The Veganic Agriculture Network claims that plant-based fertilizers are more efficient:
In fact, it would be more efficient to directly use the fodder to fertilize the soil than to feed the animals, collect the manure, compost it, transport it, and spread it on the soil.
They don’t provide any evidence for this claim, so it’s fair to treat it with some skepticism.
Now, most organic farms aren’t vegan organic, but there are some successful examples. Take, for instance, Honey Brook Organic Farm in New Jersey, which claims one of the largest Community Supported Agriculture (CSA) programs in the United States. It must be acknowledged that Honey Brook’s crops don’t include many protein-rich plants. However, the veganic Janlau Farm in Quebec grows soy, wheat, flax, and buckwheat.
I think that when Pollan talks about the need for animals to cycle nutrients, he’s drawing on his experience at Joel Salatin’s Polyface Farm, which provides what he says in The Omnivore’s Dilemma “looks an awful lot like the proverbially unattainable free lunch” (127). Indeed, it is the chickens that Pollan credits with applying nitrogen to the pasture.
These chickens aren’t simply living off the pasture, though. They also eat feed corn that Salatin buys from a neighbor who “might be using atrazine” (132). That is to say, it isn’t sustainable organic corn, but the bad stuff Pollan writes about in the first part of the book. It’s not at all clear to me that the fossil fuels used to grow that corn couldn’t more efficiently be used to grow plant-based foods.
As I wrote above, I’m interested to hear what you know. If anybody has heard Pollan further explain his claim about needing animals to cycle nutrients, I’d be interested to hear about that, too.