Going Underground
“We know more about the movement of celestial bodies than about the soil underfoot.” Leonardo da vinci
This article is excerpted from the Spring 2024 issue of Plenty Magazine. We present the initial portion of the article. You may then link to Plenty’s website to read the remainder of the piece, and see the charts and photos that accompany it.
Stand outside during the tail end of winter and the local landscape is quiet, a palette of soft grays and browns—dormant-seeming, except for the scurrying of squirrels or a line of honking geese overhead. Deciduous trees are largely bare, apart from oaks and beeches, whose dead leaves cling to them for most of winter—a strategy dubbed marcescence—but that’s another story. No new sprigs of green, no burst of floral colors. By early March, many of us are desperate for spring, overflowing with signs of its rebirth.
But just below our feet lies an entire world whose activity barely shows all winter, a vital realm brimming with as much life, if not more, than we can see in plain sight. In reality, there are more living organisms in the soil than all the other life forms above ground! When we aren’t disrupting their work, the nourishment they help liberate is ready the moment the soil warms enough to activate growth in plants and to awaken seeds. In fact, “Soil is alive. Much more than a prop to hold up your plants, healthy soil is a jungle of voracious creatures eating and pooping and reproducing their way toward glorious soil fertility,” says Kathy Merrifield, a retired Oregon State University scientist.
Some macroinvertebrate life is familiar, like earthworms—nearly 200 species, and some of the most common aren’t even native to North America! Beloved by gardeners and significant in farm fields, earthworms suck in 10-30% of their body weight daily and produce castings rich with nitrogen, phosphorus and potassium—increasing availability of these crucial elements to plants, assuming the worms have enough moisture and organic matter to thrive. Then there are the pillbugs and centipedes, essential for decomposing organic matter and aerating soil. Mesofauna, like springtails and dwarf millipedes, are often large enough to see. Most numerous are the microfauna—the protozoa, small nematodes, rotifers and tardigrades that are only visible with a microscope. All play a role in decomposition of organic matter. When pesticides are sprayed to control a particular pest on garden plants or farm crops, many of these invertebrates will die as well. Neonicotinoids, the most widely used insecticide in the world, pose a particular risk to soil invertebrate communities due to their high toxicity, systemic properties, and persistence in soils.
Ellen Gordon is a long-time environmental activist working to promote regenerative agriculture to improve food security and carbon sequestration. She chooses the outdoors whenever she can—in the fields and woods, the oceans, the mountains, and her yard.