Ever heard of mycelium, lichen, or biochar? While these names might sound like something from a science-fiction film, they are, in fact, ordinary features of the soil beneath our feet, a few of the many organisms and materials that make up the healthy living soil on which nearly all of the food we grow depends. It turns out that fertile farmland is teeming with a wide variety of organisms, including fungi, bacteria, and tiny insects, with many crop problems being linked to a loss in this diversity. According to researcher Ellie Tremblay, whose studies have uncovered links between soil life and crop health, "The role that these tiny organisms appear to have on our harvests is profound and will open doors to new kinds of farming." She envisions that restoring soil life may soon replace the practice of treating exhausted fields with heavy doses of chemical fertilizer, an approach that, with the cost of such inputs steadily on the rise, is becoming worryingly expensive.

Agronomist Carlos Mendez is unconvinced, contending that it remains unclear whether the soil changes linked to poor harvests are their cause or merely their secondary effect. "Studies have found both a decline in soil diversity and a drop in yields when farmers plant the same crop year after year," says Mendez, who acknowledges that soil organisms typically change when a field is worked too hard. He emphasizes, "It is uncertain whether enriching a field with a better balance of organisms, without an accompanying change in how the land is farmed, would make sense for overall soil health."