About 10,000 years ago, a wall of ice a mile high began to crawl out of Canada into the Midwest. The Wisconsin glaciations, as it is called, radically shaped the landscape of the Ohio Valley and much of Midwest. It was this geological event that gave Indiana, and most other Corn Belt states, the rich fertile soil that is the envy of the world. From this soil sprang up massive forests and prairies. As our nation grew and moved west, the forests were cut down and the grasslands plowed up to make room for the cities and farms of an industrial nation. As farmers learned more efficient ways to till the soil and grow food, the soil suffered. Now there is a movement to turn back the hands of time and rebuild the soil on which the world food supply depends. 

According to Hans Kok, coordinator of the Conservation Cropping System Initiative, over 100 years of plowing and planting has degraded our soils significantly. Not only have we lost tons of precious top soil, the soil that remains is not as fertile as the soil our grandfathers farmed. While tremendous strides have been made in controlling and preventing soil erosion, little has been done to address the issue of soil fertility. Improving plant genetics and low cost fertilizers let farmers increase yields year after year. But, as world food and fuel demands increase, nitrogen costs skyrocket, and land prices soar, farmers may have to look elsewhere for help in increasing production.
Kok believes that help will come in the form of cover crops. The concept of cover crops is not new. In the past, planting these grasses and small grains was a good way to keep top soil in place. But Kok says today these crops are being used to improve the fertility and organic matter of productive cropland. Research has shown that planting these crops just before or after harvest can significantly improve the texture of soils, hold nitrogen in the soil, and increase organic matter. In short, Kok says growers who are regularly using a cover crop get into the fields faster because the cover crop helps dry out soils. These growers have also reported better stands and higher yields once they start using cover crops.

Kok is an unapologetic advocate for no-till farming. He maintains that, as soon as you begin to till soil, you reduce the quality of that ground. He asserts that no-till farming and regular use of cover crops will increase yields and reduce fertilizer and input costs. He says farmers need to relearn how to manage cover crops, a practice that was common two generations ago.
Right now that education is voluntary and, in many cases, is free. There are state and federal programs that will pay a farmer to use cover crops in his operation. 

But the voluntary use of cover crops may soon take an ugly turn. There are forces in Washington, primarily at the EPA, that would love to have government controls.

There has been growing pressure by environmental activists about the amount of nitrogen and other crop runoff that moves off our fields into nearby rivers and streams. Government mandates on tillage techniques and cover crop management could be in our future. The EPA has already tried to regulate dust; can regulation of dirt be far behind?

The cover crop movement is just getting started. More research needs to be done to develop cover crops that are better suited to the Midwest. Kok, however, urges growers to give them a try, even if just on a few rows of field. He told me there are growers who have experienced tremendous benefits from adopting a cover crop system. This is the next logical step in the conservation process. First we stop losing the soil, then we have to rebuild it. Continued gain in yields cannot be accomplished by seed genetics and biotechnology alone. Improving the productive capacity of our soils is key to meeting the world food demands of the future.

The views and opinions expressed in this column are those of the author and not necessarily those of Farm World. Readers with questions or comments for Gary Truitt may write to him in care of this publication.