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Can farms help in the fight against global warming?
Yes, they can. Greenbelt’s Vanessa Johnson-Hall interviewed Alprilla Farm co-owner and soil expert Noah Courser-Kellerman to learn more.
Greenbelt: What roles do farms have in helping to prevent climate change?
Noah: Land – whether farmland or not – can hold a lot of carbon (C) in living and dead plant matter. The humus layer – that rich, organic layer where the microbes are breaking down dead vegetation into nutrients for growing plants – holds a tremendous amount of C. Techniques that build C in soil are a win/win because those soils function better for growing crops - they hold more moisture and more nutrients. It’s one and the same bringing more C out of the atmosphere and having more productive farmland if you use the right techniques to build organic matter.
Greenbelt: What happens to soils that are depleted of natural organic matter when it doesn’t rain, or when we get too much rain, or when the temperatures go to high?
Noah: If you have a soil that is pretty sandy, which is common throughout a lot of New England, and you go from 5% organic matter to 1% or 2% in just a few years of plowing and adding fertilizer. The rough rule of thumb is that every % of organic matter you have in the soil holds 20,000 gallons of water per acre. 20,000 gallons of water is almost the equivalent of ¾” of rain. So that 5% organic matter has enough water in it to keep crops going for a while without any rain.
If that soils loses its organic matter, and you get an inch of rain, most of that rain will wash through and 3-4 days later your crops will start to get thirsty. Organic matter acts as a sponge. It’s not only a sponge for water, but for nutrients. When you use fertilizer, organic matter holds onto it and releases it as needed. Organic matter is also naturally broken down by soil microbes and releases nutrients that are contained in it throughout the growing season. It evens out nutrient availability for the plants. Without organic matter, when you apply a fertilizer to the soil, more of it will wash through and end up in groundwater, or wash off and end up in surface water, and you’re more likely to have too much or not enough for your plants, so it’s harder for plants to have a well-regulated amount of fertility throughout the growing season.
Greenbelt: What are the best farming techniques for healthy soils? Organic? Regenerative? No-till? There are a lot of labels thrown around these days and it’s hard to pin down what they mean on the ground.
Noah: The current way that most farming is done in the US is not sustainable or regenerative. In some parts of the country, we’ve gone from close to 10% soil organic matter down to an average of 1-2%. That is a vast amount of carbon that has gone into the atmosphere as carbon dioxide (CO2). It’s made a lot of our soils more vulnerable to climate change events like drought, flood, and extreme temperatures.
Really what regenerative farming is about is having a landscape where you are taking crops off but also trying to build C back into the soil and rebuild ecosystems to make your land more resilient while still producing food.
I like to use terms like organic and regenerative not with a capital letter but with a small letter to keep them connected to what the word actually means. By definition, if we’re going to use farming to heal the planet, that is regenerative farming is. Which isn’t to say that harm reduction approaches aren’t warranted. I would love it if everyone started at least using cover crops or trying to reduce the amount of chemical fertilizer they are using. That would be a good start. But I think what we really need at this point in time is to take a more regenerative approach. And even what that term means is so up in the air. It’s more of a shift in our attitude, I think, that could produce some real change across the system.
Greenbelt: Weren’t many regenerative farming techniques used by indigenous populations, either native to this country or from other countries, such as Africans who were forced to come here as slaves?
Noah: Yes and no. Many techniques used in regenerative farming are borrowed from indigenous farming from all over the globe. All over the world, there are examples of peoples who found ways to farm that enhance their ecosystems instead of degrading them. History is also littered with examples from many continents of peoples who ruined their land and whose societies collapsed.
The organic farming movement really started from questions of “how do we make farming less bad? How do we not have poisons on the food we’re feeding our kids? How do we not be polluting the groundwater? How do we not be degrading our land further?” I think it undershot how farming has to be a real positive force.
Greenbelt: How so?
Noah: If you’re just trying to mitigate problems and just trying to make farming “less bad” that’s not taking full responsibility for the fact that farming could also be really good. Instead of harm reduction, regenerative agriculture believes that you can really make things better than they were before. Not just less damaging than they are now.
Greenbelt: Is how you grow the food as important as the kind of food/crops you’re growing?
Noah: Both are important. A lot comes down to the importance of diversity. If you grow any one crop year after year on the same soil, especially if it’s something that needs a lot of fertility, you’re going to deplete the soils. It doesn’t matter if you’re doing it no-till with chemicals, or conventional tillage or organically. If you grow any annual crop year after year after year, it’s not going to be good for your land. So rotating [an annual crop such as corn] with other kinds of crops allows the soil to replenish.
Greenbelt: Besides improving crop health, are there co-benefits to farming in ways that improve soil carbon-retention?
Noah: I think a really useful concept is ecosystem services. In addition to natural resources that might be harvested and sold, healthy landscapes provide benefits to all of us. One problem that farmland either contributes to or helps mitigate is rainwater retention and infiltration. If soil is compacted and doesn’t have enough organic matter to maintain its porosity, you’ll get more runoff that might contain sediment and pollution. When that soil dries out, that water runs off instead of filtering down through the soil to recharge the aquifer. Conversely, if you maintain your soil really well, and maintain a healthy hydrological cycle on your farm, when you get a massive rainstorm from climate change where you suddenly get 6-10” of water dumped on your fields, if you can have more of that go right into the soil and not run off you’re going to have less flooding downstream, less property damage, as well as less pollution and loss of soil.
Another thing worth thinking about – especially in light of what we’ve seen in the past year – is that not having our food system eggs all in one basket is really important. We’ve heard over and over from our customers how glad they are to have our food available – they don’t have to go to a supermarket. If there’s a terrible freeze in Texas and a lot of the country’s winter lettuce crop gets wiped out, they can come to our farm and still get vegetables. And we may have a catastrophic event next year, and hopefully Texas will be fine. By not having food production concentrated all in one place, we can use our food distribution systems to even out and soften the blows of the inevitable storms and other climate disasters that are going to happen.
Greenbelt: So building in that geographic diversity of where our food comes from also helps build the resilience of our food system to provide for us.
Noah: Right.
Greenbelt: I’ve heard people say that sustainable farming isn’t feasible on farms with large-scale production, like what exists in the mid-west and California, that’s it’s only feasible on small, family farms. Is it a more achievable goal in the nearer term to do regenerative farming on a smaller scale?
Noah: I think family-scale farming has a lot to do with people living in the place that they’re farming, and it’s their home, and they live in the habitat they’re creating. I think that creates an attitude that can easily adopt regenerative practices. I don’t think there’s anything intrinsically scale-related to that. Some of the leaders in the regenerative farming world are operating on thousands of acres out west or in Australia. A lot of the concepts are really scale-neutral.
Greenbelt: I want to ask you about the role that local farms can play in food equity. Climate change is disproportionally affecting people of color and other populations that have been systematically oppressed in our country. Can local farms play a role in moving toward a more equitable society, where food security is a given not a privilege, toward more food justice and racial equity in our food systems?
Noah: I think it’s important to point out that farming is not a silver bullet. Especially in a non-agricultural area such as this there’s only so much that’s fair to ask farms to do. That said, I think there are ways that the farming community and also organizations like Greenbelt can be positive forces. Just an affirmation of the idea that good food is a human right, and that the experience not just of getting food, but being in green spaces with contact with the soil and understanding how the food is grown is really important. And it’s important for everybody. Locally, we have The Food Project that works to get youths from both the City and suburbs working together addressing issues of systemic racism around growing food. Supporting organizations like that is really important.
Most of the farms I know of in this area are already engaging with hunger relief by working with organizations like the Boston Area Gleaners. Most of us also donate surplus crops whenever we can. CSA (Community Supportive Agriculture) models are pretty flexible in how they can work to break down barriers to joining a CSA. This year we worked with Nourishing the North Shore and donations from our CSA members to make lower priced CSA shares available. This is another good way of having the farmers still get paid for their work while also making it more affordable for people who might not otherwise be able to afford the food. Growing food in this area is expensive, and I don’t think it’s right to ask the farmers to bear the full weight of making food totally accessible. But I think there’s a willingness when we ask people in our communities to help out. It was really cool seeing that response from our customers.
I think land trusts have a real opportunity to play an active role in helping People of Color gain access to land. And just acknowledging that land costs are totally out of sync with the productive capacity of farmland is really important, especially in this area where farmland is often not Prime but on the real estate market it is a hot commodity. If we want to preserve land and we want to have a thriving and diverse local farming community, the open market is not going to work in favor of any farmers and especially not farmers of color who have historically been systematically excluded from access to capital by redlining and discriminatory lending practices by the USDA.
Greenbelt: Do you think that farmers who have the ability to own their land vs. leasing it will be more invested in regenerative techniques?
Noah: I think it’s less about ownership and more about security. Where if you have folks that have a 1-2 year lease, they’re only thinking on a 1-2 years cycle. So if they can get another crop out without putting lime on, they’re not going to put lime on because that’s a 10-yr payback. Why would you plant a tree on land you might not be on in 3 years? Why would you plant cover crops, why spread compost – that’s not a 1-year return. There’s a history all over the US of tenant farming being really bad for the land – and also for the tenant if you look at the history of sharecropping, for instance.
Ownership is such an interesting idea that’s very European in origin. Think John Locke and the Enlightenment. I think it’s kind of an odd concept that you can own a piece of land. But a very legitimate way of thinking about it is to ask: “how secure are farmers on a piece of land?” The more secure a farmer’ land tenure is, the more likely they are to adopt the attitude and practices of regenerative farming.
For additional reading:
American Farmland Trust report “Combating Climate Change on US Cropland”
March 16, 2024
February 21, 2024
February 14, 2024
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Greenbelt thanks the photographers whose work is featured prominently on our website: Jerry Monkman, Dorothy Monnelly, Adrian Scholes, David Alden St. Pierre & Neil Ungerleider