Stop Treating Soil Like Dirt: Why Healthy Soil Matters
“The nation that destroys its soil destroys itself,” declared Franklin D. Roosevelt in 1937.
If he was right, we have a big problem.
Fertile topsoil, in which humans grow an estimated 95% of our food, is eroding at an alarming rate. The World Wildlife Federation claims that half the world’s topsoil has eroded over the last 150 years. Just last year, scientists, using satellite technology, observed that 35% of the U.S. corn belt’s topsoil has disappeared since European settlers arrived.
The reason? Well, there are many. But a big culprit is industrial agriculture. In the search for high yields and profits, intensive agriculture has fueled deforestation, overgrazing, and monocultures of corn and soy. These commodity crops require annual planting and harvesting — more on why that’s detrimental later! — and rely on chemical fertilizers that can change the composition of the soil.
The (admittedly faint) silver lining to all this bad news: Awareness of the problem is growing.
Important books like David Montgomery’s “Dirt: The Erosion of Civilizations” and documentary “Kiss the Ground” are garnering national attention. In 2015, the U.N. held its first World Soil Day to educate policy makers and everyday eaters about the fundamental role soil plays in humans’ lives. “The multiple roles of soils often go unnoticed,” José Graziano da Silva, director-general of the U.N.’s Food and Agriculture Organization said that year. “Soils don’t have a voice, and few people speak out for them. They are our silent ally in food production.”
According to the UN Food and Agriculture Organization:
- 95 percent of our food is directly or indirectly produced on our soils.
- A shortage of any one of the 15 nutrients required for plant growth can limit crop yield.
- It can take up to 1,000 years to form one centimeter (about one-third of an inch) of soil.
- Sustainable soil management could produce up to 58 percent more food.
What is healthy soil?
Think of soil as an underground ecosystem where air, water, minerals, organic matter and billions of micro-organisms live and work together.
According to Earth Institute at Columbia University, an acre of soil may contain up to 900 pounds of earthworms, 2400 pounds fungi, 1500 pounds bacteria, 133 pounds protozoa and 890 pounds arthropods and algae. One gram of soil may hold one billion bacteria.
On a farm, micro-organisms, earthworms and insects help to break down crop residues and manures and recycle and redistribute energy and nutrients. This organic material creates what is known as structure in the soil, which helps it to retain water and nutrients and, ultimately, helps plants grow. Healthy soil also can help store and even sequester carbon, which helps to battle climate change.
How do modern agricultural practices harm soil?
Soil is affected by many things such as floods and winds. But modern agricultural practices have taken a serious toll.
An example will help illustrate why.
Imagine Farmer Sam, who manages thousands of acres of corn in the American Midwest. Running such a large farm means he must use a big combine to till and turnover the soil.
The problem? Tilling aerates the soil — releasing carbon into the air — and compacts the soil underneath, killing many of those essential microorganisms that live deep in the ground. Without a vibrant, biodiverse network of life below ground, Farmer Sam turns to fertilizers and chemicals for the necessary nutrients. In the process, however, these additives alter the chemical makeup of the soil, making it even harder for the microorganisms that remain to survive.
Degraded soil has a harder time retaining water, which in turn leads to more soil erosion and the need for more chemicals and fertilizers. Farmer Sam is stuck in a vicious cycle.
OK. But how does this affect me?
Healthy soil is the foundation of healthy plants, which are crucial for human survival. When we abuse the soil, we make it harder to grow nutrient-dense food, which as a species we need to survive. Soil also stores three times more carbon than the world’s forests and plants, so preserving soil is a key weapon in the fight against climate change.
What are the principles of healthy soil?
There are many agricultural practices that rebuild soil, but they all have the same aim: to build up organic material underground to support the rich, diverse universe of microorganisms that create healthy soil.
These include:
- Low-till or no-till farming: Farmers rarely or never plow their fields, which keeps the ground covered and protects the soil from sun, rain and wind and allows microorganisms to do their work processing energy and nutrients below ground.
- Cover cropping: Farmers plant crops simply to cover the ground (rather than for harvest) to protect the soil.
- Fertilizing with compost: Made from leaves, food scraps and other organic matter, compost naturally adds valuable nutrients to soil without chemicals.
- Increasing crop diversity: Natural systems prize diversity; a variety of plants and animals can help keep disease, among other things, at bay.
- Animal integration: Animals play a key role a vital role in building healthy soil. Grazing releases plant roots into the soil, where they create new organic matter. Their poop is a natural fertilizer.
- Holistic grazing: Moving animals from pasture to pasture to avoid overgrazing and maximize plant and soil productivity.
Do organic practices build soil?
Many consumers choose organic because the U.S. standard bans synthetic chemicals. But the cornerstone of organic farming is managing soil fertility. The ban on synthetic fertilizers and chemicals requires them to work harder at building and maintaining soil through farming practices such as crop rotations, cover cropping and integrating animals (and their valuable poop!) into their management plans.
As Sir Albert Howard, often called the father of organic agriculture, once said: “the health of soil, plants, animals and man is one and indivisible.”
Well, then, what about regenerative practices?
Regenerative farmers are seeking to correct some of what they see as errors of the organic movement; for example, creating a standard to be met (and messed with), rather than demanding continuous improvement from farmers year after year.
But there is no one agreed-upon definition of regenerative agriculture. The challenge, as it was and is with organic, will be ensuring that farmers who boast about their regenerative practices are held accountable.
At Applegate Farms, our definition of regenerative agriculture focuses on positive, verified animal impact. So we are helping to build systems in which the animals’ grazing and movement across grasslands is managed with the goal to improve their health as well as enrich the soil. (Read more about Applegate’s commitment to regenerative agriculture.)
And from the start, we have been clear that we want our ranchers to be accountable. Working with our partner, the Savory Institute, we measure outcomes on biodiversity, water retention and overall soil health each year. Our goal: to help ranchers to improve their land and their soil. For their sake — and all of our customers, too.
Want to know more? Check out these resources on the importance of soil health.
- UN Food and Agriculture Organization: Soils Portal
- United Nations: World Soil Day Information
- USDA National Resources Conservation Service: Soil Health
- The Soil Health Institute
- The Soil Association (UK)
- Rodale Institute: What is Healthy Soil?
