My earliest memory revolves around soil. I was a baby sitting in my dad’s vegetable garden, staring up at the sweet corn and wanting to taste it… but unable to reach it, I shoved a handful of soil into my mouth instead. I was very confused—I was still looking at the corn, so why didn’t the stuff I put in my mouth taste like corn? Maybe I should try again..? Nope, the second handful of soil still didn’t taste like corn.
After this very early encounter, I took soil for granted for a long time. It was dirt. It was the stuff that caked on my shoes as I hunted for arrowheads and potshards or chased after butterflies and frogs. It was just there as a barrier to prevent me from falling down into the molten core of the earth. When you’re neither a farmer nor a plant, it can be hard to really appreciate what seems to be the least interesting of natural resources…. Until you dig a little deeper.
Soil is ancient. It’s minerals beaten free from solid stone by a millennium of pounding raindrops. It’s the plants that died a thousand years ago and decayed away into water-retaining, carbon-harboring organic matter. It’s sand that once covered an ancient seafloor where reptilian giants swam. Yet it’s also completely new and ephemeral—it’s one single bacterium that was just born an hour ago but which will be long-dead by tomorrow. It’s the waste from an earthworm’s recent meal. It’s the roots of your lawn. It’s the water from the last rainstorm. It’s algae. It’s fungi. It’s insects. It’s worms. It’s life. And without it, our lives would end.
You may have heard it said that “dirt is soil out of place.” This is true—there’s no use for dusty soils stuck to your boots or dirtying up the floor of your house. But soil! Soil is intricate. It’s an ecosystem unto itself, and it needs all its myriad parts to function at its full potential just as surely as the Amazon rainforest or the Great Barrier Reef need all of their many, many pieces.
Glomalin produced by the root-like hyphae of fungi helps to maintain the structure of the soil so that it does not collapse in upon itself. Good soil structure means that the soil aggregates are light and fluffy enough to allow plant roots to penetrate easily, while also allowing for ample pore space so that water can easily infiltrate the sponge-like soil and oxygen can reach those roots. The roots tunnel deeper and deeper, sometimes dozens of feet down, creating still more pores that can then allow water, minerals, and tiny animals to follow. Eventually those roots die and the microbes break them down into nutrient-rich organic matter that further enriches the soil and allows microbes to feed and create more soil aggregates… and so the cycle continues.
Just like different ecosystems around the world have evolved to function with the unique set of players they ended up with—the rainforests with lots of plants and lots of moisture, the deep sea trenches with tremendous physical pressure and next to no light, the world’s deserts with extreme temperatures and very little precipitation—so too have the soils supporting these ecosystems evolved to be important, unique cogs in the great wheels that keep these systems going.
Take, for example, the Great Plains. For thousands of years, unfathomable numbers of American bison roamed these grasslands. The animals moved in vast herds to provide safety in numbers against large predators like wolves. As they grazed, they produced waste that covered the grasses upon which they fed, forcing them to constantly move to new areas and preventing any one area from being over-grazed. The grasses adapted to the material that the bison excreted, to the trampling of their hooves… and the soil did, too. The effects of the grazing herds meant that the soil was blanketed with a mulch that helped it retain water. Had the bison not moved through, the standing grasses would have died in place and been too dense to properly decompose. Instead, they would have oxidized and smothered the plants and soil below. These soils and grasses are far less eye-catching that the vast herds of herbivores with whom they evolved, yet once the bison were removed, the land itself suffered. They all played pivotal roles in the same large, magnificently intricate system.
If you’re a farmer, a gardener, or a nature lover who hikes in misty woodlands, chances are that you recognize the sight and smells of good earth. Enjoy it. Take a moment to try and imagine how we could exist without it. And if you have never stopped to notice it before, pay attention next time you find yourself with an opportunity to peek into this subterranean world of complex inter-connectedness. Above all, treat it well—keep it clean. Keep it covered. Keep it from eroding away. If we can do this, our soil will continue to nourish us and our fellow life-forms for millennia to come as it has, in one way or another, nourished all life that has ever existed on this planet.
Love your soils. Happy World Soil Day.
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