Down and dirty: the fate of soil in industrial society

"Common as dirt," goes the old insult. Despite its antique nature, the saying may sum up industrial (and post-industrial) society's take on soil: low, squalid, filthy, annoyingly abundent, beneath dignity and respect.

Consider the zeal to clean, to wash, to sterilize and scrub. Claudia Hemphill, a doctoral student in environmental science at the University of Idaho, has been doing some interesting work on the recent social history of soil. As US society mutated from primarily rural to overwhelmingly urban and suburban in the span of less than a century--today about 3 percent of the population engages directly in agriculture--dirt came to be demonized, Hemphill argues.

By the dawn of the 20th century, when immigrants (many of them former farmers) and our own displaced rural populations flocked into US cities, they found themslves confronted with a stark public-health slogan: "Dirt, Disease and Death.”

A society washing its hands of agriculture didn't want dirt clinging to its trousers. Hence the cult of detergent.

“So dirt became the major symbol of disease,” Hemphill says in a recent University of Iowa press release. “Anyone who was considered socially inferior--such as immigrants or different ethnic groups--was called dirty. Dirtiness was a huge insult. Housecleaning became an obsession. Even outdoors, dirt is eliminated--backyards are turned into concrete patios or covered up with gravel or bark-mulch. Dirt is so intrinsically bad, we don’t even want to see it outdoors.”

It's a well-known irony that the campaign against dirt delivered dire health consequences of its own. Modern parents who essentially sterilize their children with "anti-bacterial" soap, and forbid them to play in the dirt, have managed to wreck their charges' immune systems. It turns out that after all "we need to have some dirt in our lives," as Hemphill says. All along, it's been our metaphor for disease that's helped shield us from disease.

Yet despite better recent press, dirt still gets short shrift. Hemphill points out that even environmentalists tend to neglect the ground beneath their feet, focusing their energies on water and air.

The fragmentation of the broader society cleaves environmentalism and subverts it. Groundwater runoff from chemically fertilized fields is a significant source of water contamination; industrial agriculture's addiction to fossil fuel contributes to air pollution and global warming. Yet mainline environmentalism is curiously silent on the question of agriculture and soil stewardship. (There are a couple of proud exceptions, including Greenpeace's bare-knuckled fight against genetically modified crops.)

I think even consumers who try to shop locally for sustainably grown produce don't think enough about the soil and what it means. Every apple you eat, every carrot and every clove of garlic, represents nutrients leached from the soil--nutrients that must be replaced one way or another for agriculture to sustain itself. Same with meat. Whether a cow feeds freely on meadow grass or has field corn shovelled into its tiny hovel, soil somewhere is being leeched of nutrients.

I wonder if many vegans ponder the ultimate source of their nutrition. Small-scale farmers who reject synthetic inputs have essentially two options for replenishing the nutrients they pull out of their soil: animal manure and what's known as "green manure," plants capable of leeching nitrogen out of the air and depositing it into the soil. (Compost could be considered a third option, but farm-scale composting typically relies on a heavy dose of manure--not the green kind.)

Most small organic farms use both methods. Green manure by itself would be a tricky option. First, the seeds tend to be expensive (for example, hairy vetch), and small-scale market farming is a notoriously seat-of-the-pants proposition.

Second, using green manure as the only fertility strategy imposes opportunity costs. Say a farmer wants to use the same bed to grow several different crops in succession over a single season. Green manuring would require her to devote parts of her fields all season to growing cover crops for the sole purpose of tilling them in. Again, that's tough to pull off on a typical small farm, where there's intense financial pressure to produce as much as possible for market. In the heat of the season, it makes more sense to simply work in some well-composted manure before planting the next bed.

Thus vegans who shop at the farmers market are faced with a stark fact: that beautiful carrot you just enjoyed likely spent its growing life swaddled in a rich bed of decomposed animal shit. Try as we might, we can't shake off the scatological origins of life, any more than we can meaningfully win any war against dirt.

I mention this not to take a poke at the vegans, but rather to remind them of the importance of animals in the nutrient cycle of farming.

And this points up another vexation of small-scale farming in an industrial-scale world. Fertilizing by manure is less difficult than a purely plant-based strategy, but not by much. Industrialization has rent farming in two. For the most part, there are animal farms and meat farms; few do both. Thus vegetable farmers tend to spend a lot of time wrangling and making deals to get tremendous loads of manure delivered to their farms. And since small-scale meat and dairy production has collapsed in most areas, even the most conscientious organic farmers end up using manure from industrial farms.

Vegans and anyone else interested in organic local vegetables thus have an interest in supporting humane, pasture-based animal farming in their areas.

Scientists, too, have tended to neglect dirt. Hemphill conjectures that they recoil from the inherently murky nature of the stuff. Water can be filtered to its elements: two hydrogen atoms linked to one oxygen. No such luck for soil. Hemphill puts it well:

If you take a sample of water from the stream and filter out the leaf bits and twigs, insects and impurities, you’re left with pure water. If you take a handful of soil and remove the rock particles, pollen grains, decomposing wood bits, water and microorganisms, you’re left with nothing. Philosophically, this makes it cognitively unmanageable because it bypasses our tendency to want to sort things out into little piles that are all the same.

Healthy soil literally lives and breathes; it's made up of decomposing matter and live organisms, from tiny bacteria to earthworms as big as your finger. Healthy soil is like a decadent poem: fevered activity, death, life, rebirth, green leaves and lovely flowers rooted in a bed of seething scatology.

A society that fails to study that poem risks extinction. Consider that field corn--the fodder that's fed to confined animals and makes its way into food-proccessing factories and ethanol plants, not the sweet stuff you eat off the cob--is the number-one U.S. crop, heavily underwritten by federal subsidies. No crop erodes soil faster than field corn.