Don't Treat Dirt ... Like Dirt

We don't value dirt. It's bad to be dirty. Taboo words are "dirty." An object of little to no value is "cheaper than dirt."

But dirt deserves some respect. It's incredibly valuable: Without dirt, we would not eat. And, like oil or coal, dirt is a nonrenewable resource. When topsoil disappears from erosion, it takes thousands of years for that layer of dirt to build back up. And we're running out of it.

This is one of those problems that people have known about for a very long time. Pliny the Elder wrote about it. Thomas Jefferson dedicated some of his ample brainpower and technical savvy to designing soil-saving techniques for his farm. And as The New York Times points out today, the U.S. government has been fighting soil loss for decades:

Significant gains were made in combating erosion in the 1980s and early 1990s, as the federal government began to require that farmers receiving agricultural subsidies carry out individually tailored soil conservation plans.

Because this problem has been studied for centuries, there's a lot of information out there about how to fix it or, at least, minimize its impacts. Even better, soil conservation techniques make farming more profitable in the long run. They can be more labor intensive up front, however, and short-term incentives push farmers, particularly ones renting land, to tear up land and begin farming it without worrying about the fate of the dirt they're mining for nutrients.

The government can help push back by requiring farmers to adopt plans that are better over the long term. But rules can only go so far. More from the Times:

…Environmentalists claim that enforcement of conservation plans by the United States Department of Agriculture is not as strict as it should be and that the gains in fighting erosion have stalled or are being undercut.

U.S.D.A. data shows that the amount of farmland erosion nationwide from water fell substantially from the early 1980s to the mid-1990s, then largely stagnated.

FDR wrote in 1937 that "a nation that destroys its soil destroys itself," which sounds dramatic but is not overstating the case. In Dirt: The Erosion of Civilizations, geologist David Montgomery lays out how soil erosion undermined all those glorious civilizations we learn about in middle school. All those rocky outcroppings on the hills of Greece? Didn't used to be there; farming loosened a richer layer of dirt that sloughed off the mountain and left the hillsides exposed.

There are ways to prevent this loss from happening here. The Environmental Working Group, which released a report today on soil erosion, says that conservation measures can prevent 97 percent of loss. To get geeky about this stuff, check out the group's entire report.