Advances in genetics and traits promise to accelerate yield increases in U.S. corn and soybeans. Some scientists and experts even say yields will double by 2030. But what's often missing from the conversation is the critical role of soils.
Soil scientists remind us that even the most elite crop varieties need well-managed soils to provide the nutrients and water essential for high yields. "U.S. corn and soybean farmers already are feeding whole nations," says Jennifer Shaw, head of sustainability for Syngenta. "As we coax even more yield from every acre, soil health will become just as important as crop health in our drive to double food, feed and fiber production."
Soils in U.S. Corn Belt are degrading and that must be stopped
Soils in the Corn Belt are among the worlds most productive, but they are degrading at a rate that will affect productivity unless we reverse the trend, points out Kendall Lamkey, chairman of the Agronomy Department at Iowa State University. Despite major gains in soil conservation, Iowa leads the nation in soil loss by water. Illinois is a close second in that soil erosion category.
"It's hard to really appreciate just how good our ground is until you've seen farmers in developing countries trying to grow a crop in soil that has been severely eroded and depleted of organic matter," says Lamkey. "What we have is a very precious natural resource that needs to be maintained and nurtured so that it can keep producing at the levels we expect."
Raising the bar for soil conservation efforts is needed
The effort to save soil is an on-going need. Saving soil, toil and oil was a popular rallying cry of the 1980s conservation tillage movement. Syngenta legacy companies played a major role, helping to replace tillage with weed control technologies like Gramoxone Inteon herbicide and by supporting creation of the Conservation Technology Information Center.
"The goal of programs like T by 2000 was to reduce soil erosion to a level where the rate of soil loss would be equal to or less than the rate of soil replacement," says Shaw. "Now the focus has expanded from saving soil to improving soil. We need the foundation of a healthy soil to bring plant potential to life."
To help raise awareness of soil's role in feeding the world, Syngenta recently co-sponsored "Dig It! The Secrets of Soil," an exhibit at the Smithsonian's National Museum of Natural History. In the field, Syngenta continues to champion conservation tillage through advances in genetics, traits and crop protection, as well as stewardship of glyphosate-tolerant technology.
Technologies such as herbicides for no-till must be preserved
"Glyphosate gives us a very cost-efficient way to meet the challenge of weed control with low or no tillage, but the emergence of glyphosate-resistant weeds threatens to take this very valuable tool away from us," says Chuck Foresman, manager of weed resistance strategies with Syngenta. Some farmers in the South are reverting back to tillage as the only available alternative for controlling glyphosate-resistant horseweed and Palmer amaranth or pigweed.
"This is the worst-case scenario and it's exactly what we're trying to avoid with our Resistance Fighter program," says Foresman. "The goal is to keep glyphosate-tolerant technology viable through the use of Resistance Fighter brands that incorporate multiple modes of action." These include Gramoxone Inteon across all row crops at burndown and Halex GT, Lumax and Lexarherbicides for corn; Prefix, Boundaryand Flexstar GT herbicides for soybeans; and Reflex and Sequence herbicides for cotton.
Without management changes, Foresman says around 39 million row crop acres could be infested with glyphosate resistant weeds by 2013, leading to increased tillage and soil loss.
Building soil organic matter is key to long-term yield gains
"Anytime soil moves, I call it dirt because we lose the organic matter and micro-organisms that make soil a living, breathing and very productive natural resource," says Lamkey.
Tillage also takes a toll on organic matter in flat ground, points out Jerry Hatfield, director of the USDA's National Laboratory for Agriculture and the Environment, located on the campus of Iowa State University at Ames. "Every time we till the soil, we release carbon and lose organic matter," he explains. "To support the yield potential of advanced traits and genetics, soil scientists recommend reducing or eliminating tillage to maximize carbon storage."
Hatfield points out that "Carbon may be bad for the atmosphere, but it's very good for our soils. It's the major ingredient in organic matter and the glue that holds soil together and makes it work better."
Important to realize why soil organic matter is so critical
Organic matter absorbs up to six times its weight in water and holds up to five times more nitrogen than clay. It improves water infiltration and holding capacity, encourages root growth, and minimizes yield reductions from short-term weather extremes, like heat, drought or driving rain. "Improving water infiltration is especially important in the Midwest because weather patterns here are trending to less frequent, but more intensive, rainfall events," notes Hatfield. Through a combination of carbon management practices, including conservation tillage, he says growers can improve crop productivity within three to five years.
Syngenta is one of the world's leading companies with more than 25,000 employees in over 90 countries dedicated to our purpose; bringing plant potential to life. Through world-class science, global reach and commitment to its customers, the company helps to increase crop productivity, protect the environment and improve health and quality of life. For more information, visit www.syngenta.com or www.growmorefromless.com.