Soil -- from dirt to lifeline: Fred Kirschenmann at TEDxManhattan

Transcriber: Rhonda Jacobs Reviewer: Denise RQ It may seem strange to some of you to talk about

soil

at a food conference. And the reason for this is that, for most of us, we have created a food culture that essentially views food as a commodity. Many of us don't even know why it has anything to do with food. And I want you to know that I am not a

soil

scientist; As you may have heard, I am a farmer. But I have the privilege and honor of having an association of colleagues and friends who have helped me a lot with this, and that is why I want you to recognize the credits that I want to give to all the people who have helped me talk about this. both soil and food.

In this food culture where food is essentially a commodity, I think most of us, in our culture today, just think of soil as land. It's just that black thing that's out there. And even some of our soil scientists have occasionally talked about soil as simply a material to hold a plant in place, and the way we grow food is everything else we do: all the synthetic fertilizers we put in, the pesticides we use . , that's what we use to grow food, and the soil is there. But, in reality, the soil is essential. And what I want to do this afternoon is help you understand some of that.

And first of all, the first thing to understand is that soil is not earth. In fact, the soil is a living and vibrant community. In fact, soil scientists, some of the things they tell us now is that there are more living organisms below the soil surface than on the soil surface. And it's not just all the things we can see, the worms, the beetles and the ants, but it's those microorganisms that dominate our entire soil culture. In fact, as far as I can tell, soil scientists can't even agree on how many microorganisms there are in soil.

I've seen some soil scientists refer to that as 50 million microorganisms in a single teaspoon of soil, and others have said it could be between two and four billion. So this is a community of life, and if we want to have not just good food but any food, we have to sustain that community of life in the soil. This is one of the things I want to help us understand today. And so, if it weren't for that community of life, we wouldn't have food, we wouldn't have water, we wouldn't have any of us. And so I love the way Wes Jackson puts this because not only are we very dependent on all that life for our life, but as we all know, we eventually come back to earth, right?

So the way Wes put it is that we're just scales between ground and ground. (Laughter) And I think it's important that we try to appreciate that as we try to come to terms with changing the way we eat, because we're not going to change the way we eat unless we recognize what we have to do to support our soil. Now, there are a couple of problems with this, and one of those problems is that currently, in the way we produce our food, we are losing our soil at an unprecedented rate. In the last half century alone, we have lost about half of our topsoil in this country.

And we have not only lost it, but we have also degraded it. A recent United Nations study just released indicates that 25% of the land left on our planet is currently degraded. In other words, it no longer has the vitality to produce the kind of food we've all heard today we need. The other thing is that soil is not essentially a renewable material, it is not a renewable resource, because it has taken the Earth millions of years to accumulate this soil. So unless you want to stay there for a million years, it will be very difficult to see this soil that we have lost and are losing, restored.

So I want to share with you about a minute and a half of a wonderful documentary that Deborah Koons García has spent the last four years making and that will be released to the public in March of this year, called "Symphonies of the Soil." ", and I hope that all of you will have a chance to see it when it comes out, but John Reganold, a soil scientist at Washington State University, at the beginning of this film, tells us how nature developed and accumulated this soil in the various landscapes .Well, let's take a moment and listen to John tell his story. (Video) John Reganold: Soils have parents, just like we have parents, so they came from somewhere and soils are formed from some material. which is found in a particular location.

So in this location, we had windblown sediments that came in, and you have these loose sediments that are mostly silt-sized particles called loess - L-O-E-S-S, with some clay and some clay. sand, and then the soil was formed. That type of material is transported. Parent material is transported because it arrived by the wind. Other types of parent material can come in by water. You can have rivers that overflow, like along the Mississippi. , which deposit alluvium. Water rushes off a mountain range and can drop a large amount of material, like an alluvial fan. When they deposit that material, new soils form in that material.

And then we also have the material transported by glaciers: soils that formed in glacial sediments. When those glaciers melt, they drop the material. We also have soils that are not transportable. We have soils that form in place. Right where we are now, we are on a hill, a kind of ancient mountain range. On this particular mountain, the soils were formed from rock in place. I was exposed; After probably a million years, we had soil that actually formed in that rock. So, transported soils; Generally speaking, I would guess that 70-75% of our soils were formed from transported parent material.

Then another 25% formed in the soils already in place. Many of them are in the mountains. Fred Kirschenmann: Okay, so it took nature millions of years to accumulate this soil. Now, there is another problem: namely, that we are now losing soil at an even faster rate, mainly because as climate change comes into the picture, we have more severe weather events. This is what a lot of the landscape was like in the heart of the country, where we have some of the richest soil, in the spring of 2008, when we had two weeks of incredibly heavy rain, and this is what we saw in the landscape, so we've been losing that ground now and is threatened at a much, much faster rate than even in the past.

So now it's easy to just blame the farmers and say, "Well, look, farmers should be better managers, they should take better care of this," but the thing is, we've all been part of creating a food industry. system that puts farmers in the position that they have to do simply one thing, and that is, produce the greatest amount of food at the lowest possible price. So what they do now, what they have been put in a position to do, is concentrate the animals in one place, as we heard about today, because presumably it is a more efficient way of producing meat and, our crops now they're produced in these huge monocultures, because again, it's a more efficient way to produce food as cheaply as possible, so the picture now looks like this.

So we don't have any of that diversity that is part of the need to create that biologically healthy soil that actually feeds that whole living community below the soil surface. Now, fortunately - you may get tired of hearing me talk about all the problems - there is good news, because we know that there are alternatives. A friend of mine, Matt Liebman, who's an agronomist at Iowa State University, has done eight years of research in which he's just taken these research plots as a no-brainer. Suppose instead of having this two-year rotation, which specializes only in corn and beans, we had a three-year rotation, where you have corn and beans, and then you have a small grain with clover interspersed, and then the clover, for example.

Of course, it is a legume, so it fixes nitrogen in the soil, and then that rich green plant material is incorporated into the soil as green manure; All of this begins to feed that living community in the soil that it needs. Or compare it to a four-way rotation where you have corn and beans, and then the small grain with alfalfa, and then another year of alfalfa. What Matt has discovered, if that is done, we could reduce our pesticide use by 97%, we could reduce fertilizer use by a little over 90%, and return land and labor to farmers. It could be somewhat larger than in this specialized corn. and soybean rotation.

And a farmer named Dick Thompson in Iowa has, in fact, adopted some of this type of diversified agriculture. And what soil scientists have discovered, instead of having 18,000 worms per acre in their fields, which is pretty typical; It may seem like a lot, but there are 1.3 million earthworms on Dick's farms. And the organic matter, instead of being just over 2% organic matter, is now 6.5% on his farm. So we know some of the things we need to do. This is the difference in what the soil looks like in that two-year rotation and in the three- and four-year rotation: it is more porous, it has more organic matter, it is that community, that habitat that is needed to produce the type of food we need.

And then at the Land Institute in Salina Kansas, where geneticists have been developing a perennial variety of grain like wheat and sorghum, etc., instead of an annual, if you look to the left side, that's the root system of a perennial plant. crop; on the right side, from an annual crop. It's a much denser root system, it goes into the soil 15-18, it makes the plant more drought resistant, and of course, again, it does exactly what needs to be done in that soil habitat for that entire community. live on the ground. And again, here is the living evidence: the hand on its right side - this is, by the way, all from the same field, it's just that on the right side is where the perennial crop is grown, on the left- side Right is where the annual crop is grown.

And again, that's the community, on the right side, that a living community needs. And then we have researchers and farmers who are now working with winter cover crops. In other words, when you simply use the land to grow food, then you have living plant materials there probably four or five months out of the year. The rest of the time the soil remains inactive; It is not an ideal condition for that entire community living on the ground. If you put a winter cover crop in there, you'll get all kinds of benefits. Cover crops absorb a lot of nitrogen and other nutrients from the soil and retain them in the plant during the winter months so they don't leach into streams into groundwater and into the dead zone in the Gulf. from Mexico, but it stays there on the surface of the ground.

And then when you replant food crops, you incorporate them into the soil and put those nutrients back into the soil. And then along with some compost, this is what you see, what the soil looks like when you use these winter cover crops. And again, it provides that community for all those living organisms in the soil. And then we have another approach, which uses what is called permaculture. where, especially young farmers, are now finding ways to look at the farm, really as an organism, where all the plants and animals in the system support each other and provide goods and services to each other, which again allows this . that healthy soil emerges and animals can perform all kinds of services.

Here, for example, the turkeys are in a pumpkin patch eating the bugs, so take care of that so you don't have to use an insecticide. All these benefits. And then, of course, compost is absolutely critical in all of these different types of approaches. Add compost and use all this; You know, about 80% of the material that we put out on the curb for garbage collectors to pick up and go to landfills could be composted and could be used to restore soil in our own communities. And again, this is what the earth looks like when you add that.

Now, how are we going to achieve these changes? Well, part of it is that changes will occur because all the resources that we use to maintain our current system without paying attention to the soil, such as oil, phosphorus, phosphate rock, all these materials, we are decreasing and as As we do, they become more expensive. And as this recent United Nations study points out, every time the cost of the energy we need to produce that food increases, the cost of food increases. Then at some point it will simply become unaffordable. That is the dark side of what will bring about the changes.

You probably wouldn't have expected a photograph of chefs in a story about the earth. But now we have a new school of chefs that we call farm-to-table chefs, and they haveThey discovered that the easiest and most effective way to get the type of flavor they want in the food their customers want to serve, is to grow the food in this type of rich soil. Now they are rewarding farmers, working with them, to manage the soil this way, grow the food this way, and serve it in their restaurants. And then we have a new generation of young people across the country who want to do this.

They want to learn how to manage the land in this way; They want to learn how to produce food this way, and produce food for those chefs, and for farmers markets, and for CSAs, so that we can all afford it. Then there is the next generation behind this generation, and those are the children. All over the country we are starting to have gardens; We're starting to have kids come to places like the Stone Barn Center where I'm connected. We now have 10,000 children coming to learn how to care for the soil and how to grow food, and they will become the next generation that will allow us to do this.

And then there's something that any of you can do that people are doing, and that is that you can buy or even make your own compost bin for your own backyard. And all those food waste in your kitchen and leaves in your garden can be composted and placed in your own garden, on your own lawn. And this is one of the most important things we can and should all do because the most important inheritance we can leave our children is biologically healthy soil. It is our

lifeline

to the future and each of us can help make that happen.

Thank you. (Applause)