Saving Soil
In the 1930s, farmers and their families in the American Midwest often looked to the sky dreading what they might see. No, it wasn't tornadoes that had them worried - it was dust storms that could carry away millions of tons of fertile top soil - and their livelihood - in mere minutes.In 1935, the dust storms reached Washington, D.C., and provided a platform for Hugh Hammond Bennett, advisor to President Franklin Roosevelt, to testify before Congress about the need for soil conservation legislation. That year, Congress unanimously passed legislation placing priority on soil and water conservation, which led to the establishment of local conservation districts and put in place practices to protect this vital natural resource.
The resulting evolution of U.S. farming practices, and the influence of the Soil Conservation Service (SCS), can be vividly demonstrated through a study of the Coon Creek Watershed in Wisconsin. In the 1930s, frequent, intense floods washed away the soil from small, rectangular fields in the region, reducing farm productivity and filling streams with sediment. In one of the first large-scale erosion demonstration projects in the country, strip-cropping was introduced. The method was rapidly adopted and dramatically reduced erosion at least 75 percent from 1934 to 1982.
Around the globe, conservation of soil has become an issue of survival. Erosion in Haiti has stripped soil in many places down to bedrock with food production per capita falling 30 percent from 1991 to 2002. Farmers in Central China constantly rebuild silt terraces that are no match for the wind and wash into the Yellow River. Parts of central Africa are still struggling to recover from intense farming during a time of unusually high rainfall in the 1950s that left the region with impenetrable soil.
As agriculture seeks to sustain a rapidly growing population in these coming years, restoration and protection of soil around the world is vital -- and possible. A recent National Geographic story about global soil conditions describes the efforts of small farmers and scientists around the world as they work to improve soil made unusable by years of degradation. One particular African farmer, determined to remain on his land, combined a soil restoration technique called cordons pierreux, in which lines of stones are placed to prevent rain from washing over the soil, with a technique in which numerous foot-deep holes are dug in the field and filled with manure. Termites, attracted to the manure, enrich the soil with digested organic material and a tree is planted in each hole. From 50 acres of barren land, this farmer slowly created a private forest.
Giving new life to formerly barren soils is one innovation that will be vital to meeting the needs of 2050. We just need to keep learning from one another - and remember that soil is worth a lot more than "dirt."