SOIL MATTERS

Just beneath our feet is the ultimate natural resource

BY VICTORIA SPENCER
ILLUSTRATIONS BY LUCY ENGELMAN

We often call this stuff “dirt,” but that has negative connotations— as in something to avoid and eradicate from our day-to-day lives. Scientists usually refer to it as “soil,” though that also has similar negative implications. Biodynamic farmer Hugh Williams, of Threshold Farm in Philmont, Columbia County, prefers to call it “earth,” saying, “that keeps it positive.”

Though there is so much of it and it has been around for so long, we know relatively little about soil. Reich admits it’s “a hard thing to study; it is underground, it is the ground, and it does change with the time of year.” We’re far more removed from the soil than our grandparents were, as much of our daily path is well covered with asphalt, concrete and the like. Williams notes the contemporary cultural obsession with and fear of bacteria, an essential element in soil, effectively drives a wedge between people and earth. Our frantic use of antibacterial soap to rid ourselves of the dreaded bacteria amuses Williams; “I’ve gradually come to the idea that oneness is to be completely identified with the earth, completely identified with its bacteria, not be separate from it.”

Skin Deep

Reich defines “soil” as “a mixture of living and once living things that supports life on Earth.” Williams echoes its importance, saying, “It’s the living membrane of the planet.” It’s a mixture of air, water, minerals and organic material, such as decaying plants, earthworms, bacteria and microorganisms. Soil is highly stratified and certainly not the same six inches down as it is six feet down. It is composed of distinct horizontal layers called “horizons,” which range from rich, organic upper layers (called “humus” and “topsoil”) to underlying rocky layers (subsoil, regolith and bedrock). Healthy soil is crucial to the long-term survival of the planet because it is essential for the production of crops (as well as wild foods) used to sustain humans, our livestock, as well as wild animals. It provides the base that supports plant roots and stores the water and nutrients needed for plant growth. The bacteria, nematodes and tiny arthropods in soil all cycle nutrients back to plant life.

“We’re far more removed from the soil
than our grandparents were, as much of
our daily path is well covered with
asphalt, concrete and the like.”

Healthy soils are the foundation for developing sustainable farms and gardens. If the soil is healthy, there’s a better chance plants will be healthy and will produce healthy fruit and vegetables. The Yale Sustainable Food Project reports that plants grown in healthier soil have higher levels of minerals and nutrients. Reich explains soil health is basically a matter of getting the correct combination of air, moisture and the microorganisms that make or keep the soil healthy and in turn keep the plants in the soil healthy.

Unfortunately, many things humankind does damage and deplete the soil. Industrial agricultural practices such as mono-crop agriculture systems (the practice of growing one crop year after year without rotation) cause nutrient depletion and wide-scale soil erosion, while overapplication of fertilizers and pesticides contaminates soils and pollutes waterways.

Abused soil can be as lifeless and inert as a sandbox if it is loaded with harmful chemicals. While healthy soil acts as a sponge retaining water and nutrients, and sequesters carbon for hundreds of years, weakened or “dead” soil acts more like a sieve, leaching water and nutrients and releasing carbon back into the atmosphere where it traps heat and warms the planet.

Gregg Twehues, director of nutrient management at Stone Barns Center for Food and Agriculture in Pocantico Hills, Westchester County, explains how artificial fertilizers, which often have a high salt content, affect soil health on even a garden scale: “The biological communities present in soil want to live in a low- or no-salt environment. So when petro-chemical fertilizers are applied year after year, basically those communities are driven downward and the soil becomes dependent on the application of those fertilizers.” The soil becomes an unsustainable system artificially propped up with industrialized stimulants, akin to a junkie kept alive by the very substances that are slowly killing him.

Fortunately, many farmers are choosing to use simple sustainable agricultural techniques, such as crop rotation and organic fertilization, in order to protect soil resources. “The earth is living, the soil is inherently alive. We need to foster and manage it, to create a strong nutrient cycle,” insists Williams. For Williams and for many other farmers and gardeners, compost, a nutrient-rich mix of decaying organic matter (typically leaves, grass, and food waste) is an essential element in creating a strong nutrient cycle and a healthy farm or even backyard garden. Twehues, who farmed conventionally for most of his working life, contrasts inert soils treated with petrochemical fertilizers with those to which compost is added, “When you apply compost, there’s a rejuvenation of soils. On a farm scale, I found I didn’t need to add additional fertilizers. The same is true with a garden, you see the worms come back, fungal communities pop up.” Compost helps soil physically, chemically and biologically. “Physically,” says Reich, “adding compost to the soil aerates the soil and increases its ability to hold moisture.” Chemically adding compost “has far-reaching benefits. It helps soils to take up certain nutrients they otherwise have difficulty absorbing and adds other nutrients to the soils. And biologically it promotes microorganisms that help fend off pathogens.”

So Wasted

In our society, organic matter, which had effectively been the building blocks of compost, has become a cast-off waste product. Reich remarks: “The arborist has to get rid of wood chips, at the landfill people bring their kitchen waste and leaves and grass clippings. This is a social problem.” As well as a significant environmental problem. Such organic matter is bulky to dispose of. Kitchen waste goes to the landfill in plastic bags, and, as Reich points out, the landfills have rubber liners “so think 10,000 years (for the plastic bag to break down), plus the rubber liner.” According to the E.P.A., decomposing food that is buried and cut off from air releases methane, a potent greenhouse gas greatly impacting climate change.

“I’ve gradually come to the idea that oneness is to be completely identified with the earth, completely identified with its bacteria, not be separate from it.”

Instead, when we use it as compost, we are cutting down on waste and improving soils. Twehues says 35–40 percent of the materials going to processing landfills and waste-to-energy plants (a way of generating electricity from the burning of municipal waste) are compostable. Compost is a reductive process; if 100 pounds of raw compostable material is composted, it reduces down to 50 pounds of nutrients to add to soil. And as compost is ventilated, it prevents methane creation. As global oil supplies move beyond peak, society needs to consider the best use of remaining oil. Packaging garbage in trucks and hauling it hours away, as many municipalities do, is assuredly not beneficial to our world. There are also the various carbon costs of our current practice of hauling waste rather than dealing with it at a community level. Composting on a community scale where the waste is created would also increase safety and air quality (fewer trucks on the road), as well as reduce consumption of fuel.

As people become more and more divorced from gardening and from growing their own food, more distanced from how their food is grown, there are fewer people aware of how varied and essential soil is to our livelihood. It’s much more than something we walk on, a substrate for plants. Soil is a living organism. Healthy soil breathes and delivers nutrients to plants more effectively, and is less susceptible to wind and water erosion than damaged soil. Healthy soil and its cohort compost are a vital part of our ecosystem. The health of our soil is as important as the condition of our water supply (as the two are inexorably intertwined). The soil holds and cleans our water while providing a literal grounding for all living things on the planet. Yes, it’s another thing to worry about but, well, we can’t just treat it like dirt.

COMPOSTING 101

Composting is a relatively easy and very rewarding process. From seeing how much less waste goes into your garbage to having rich “black gold” to add to your flower beds or vegetable plot you’ll get a deep sense of satisfaction from composting. Still many are discouraged, confused or simply turned off by the prospect of composting in their own backyard, but it is as easy as dirt.

Here’s some basic information to get you dirty and on your way to a healthy compost pile (note: starting a compost pile in the winter provides a certain challenge, and you may not see the richness of the decay until well after the first thaw): Location: Compost should be in an area that is easy to access, both to add to the compost bin and to get mature compost to add to the garden. A spot adjacent to your garden is ideal. If the garden is fully fenced in, designate a place in the garden for compost. You’ll find that biological communities gravitate to that area and will grow around the compost and into the garden. Containers: A compost system requires three containers, one to collect material into compost, one that is full and composting and one with mature/finished compost that can be added to the garden—and which when empty will become the container to add material to. “It’s not necessary to go out and buy containers to compost in,” says Twehues. “Anything that is able to hold material becomes your ‘bin.’” He suggests square bins constructed of pallets (that have not been in contact with chemicals), with hardware cloth on the inside so that plenty of oxygen gets in but potential pests like raccoons and squirrels cannot. An alternative compost structure can be made from fence posts wrapped with wire. The size of the container depends on the amount of food waste your family creates. Twehues says a three-by-three-foot container about four feet high generally suits a family of four.

Ingredients: Not all biodegradable materials are appropriate for at-home composting. Most backyard systems will not reach temperatures high enough to kill pathogens, so meat or dairy products should not be composted and left out of your compost bin. Twehues advises cutting citrus and watermelon, both of which add a lot of moisture, into small pieces for composting. Shells (eggshells as well as mussel, clam and oyster shells) are good additions, as they add minerals to compost.

Unbleached paper towels are a fine addition, but Twehues counsels against adding other paper or cardboard unless you know its source and how it was produced.

Recipe: To create a light and fluffy compost, add a ratio of 1:1—one 5-gallon bucket of leaves to one 5-gallon bucket of food waste. Add food waste in the center, not at the sides, as the temperature is higher in the middle, and it’s the heat that “cooks” the compost, speeding its decomposition. Grasses can be added at the sides.

Twehues suggests adding sticks about 1 1/2-inches in diameter, laid across the compost. They will add oxygen to the pile and reduce the need to turn the compost. When that bin is ready, the sticks can be removed and added to another bin. By then they’ll be hosting various biological communities that will benefit your compost.