The Virtues of Soil

By Melinda Hemmelgarn

Rodale Institute

June 12, 2008

Available online at: http://www.rodaleinstitute.org/20080612/n1

Sir Albert Howardappreciated the virtues of soil. That’s "soil," as in your basicgarden-variety earth that many of us treat like dirt. The British botanistbelieved that humus-rich soil, the miraculous medium from which our nourishmentsprings forth, pulsates with life and forms the basis of public health. In the1940s, Howard said: "The real arsenal of democracy is a fertile soil, thefresh produce of which is the birthright of nations."

Today, many scientistsagree with Howard’s groundbreaking idea that soil microorganisms are the unsungheroes of healthy environments. Earthworms, bugs and the millions of microbesin a single handful of soil break down organic matter, such as leaves, decayingplants and animal manure and release the nutrients plants need for optimumgrowth.

Native farmers in Barbadosand India taught Howard about the critical nature of soil and theinterdependence of soil, plants, animals and humans. Think of it this way: Weneed healthy soil to produce nourishing food, which protects the health ofanimals and people. Healthy people create vibrant communities.

Howard realized decadesago that chemical fertilizers and synthetic herbicides and pesticides depletethe soil, which leads to public health problems, including disease andenvironmental destruction. Yet according to the National PesticideUse Database, in 2002 more than 675-million pounds ofpesticides were applied to crops in the United States alone.

Thankfully, the Universityof Kentucky Press has recently reprinted Howard’s The Soil and Health. Originallypublished in 1945, the book largely inspired our modern-day organic movement.

The time has come tore-think Howard’s words, especially in light of recent research showing what’sin organically grown food might matter as much as the missing syntheticpesticide and herbicide residues. For example, research at the University ofMinnesota and the University of California-Davis found that organic farmingmethods yield produce with higher levels of nutrients, especially over time, assoil has a chance to accumulate organic matter. Researchers compared tomatoesharvested over a 10-year period from two matched fields, one organic and theother conventional (which included commercial fertilizers).

Over time,health–protecting antioxidants, called flavonoids, increasedsignificantly in the tomatoes grown in the organic fields but not in theconventionally grown tomatoes. The researchers explained that higher qualitysoils cycle nutrients more efficiently, making them more available to plantswhen they need them. Other studies have found higher levels of vitamin C, ironand magnesium in organic crops, lower levels of potentially harmful nitratesand better taste. In general, organic production methods can raise healthfulantioxidant levels in fresh produce by about 30 percent.

The benefits ofsoil-enhancing organic farming methods extend beyond nutritional composition.For example, at Iowa State University, horticulture and agronomy researcherKathleen Delate discovered higher yields, increased profitability and steadilyimproved soil quality in organic over conventional fields. Improved soilstructure protects against erosion and improves the soil’s ability to hold ontowater during a drought. The United Nation’s Food and Agriculture Organizationrecommends organic farming to help fight hunger and tackle climate change.

Unfortunately, we tend toprogress in a linear fashion, without reflecting on the wisdom published orspoken decades before us. Andrew Kimbrell, director of the Center for FoodSafety and author of Fatal Harvest: The Tragedy of Industrial Agriculture,suggests we question that approach. "When we speak of progress, we shouldask ourselves: Progress towards what?"

Today’s conventionalagribusiness has replaced agriculture, leading us down a narrow and dangerouspath toward shrinking biodiversity, weakened resilience and unhealthy soil andwater. Luckily for us, the recent groundswell of organic demand might save oursoil and our society.

Melinda Hemmelgarn, M.S., R.D., is a registered dietitian, advocate for sustainablefood systems, and Food and Society Policy Fellow. She’s based in Columbia, MO.©Food Sleuth 2008.