Rains can wash away benefits for corn

While spring rains are a welcome sight for farmers, a new study shows they can take away as much as they give. A ten-year study at Iowa State University examined the link between rainfall and the nitrate concentrations in cornfields. Nitrate is a form of nitrogen the corn plants need from the soil, and is usually gained by the application of commercial fertilizer or manure to fields. Alfred Blackmer is an I-S-U agronomist and lead researcher on the project. He says when there were small amounts of rainfall in the spring, March through the first of June, there were high concentrations of nitrates in the soil. When they had more rainfall, there were smaller concentrations of nitrates in the soil. Blackmer says the study shores up some of the information they’ve known about nitrates.He says it’s been know for a long time that nitrates move from the soils into the rivers. He says this study shows a little better relationship link between the loss of nitrates and the nitrate concentration in rivers. He says it also update some of the information on the loss of nitrates. He says they found the nitrates wash out of the soil and into waterways at a much faster rate than previously believed. And he says it was believed the loss of nitrates didn’t hurt profits much, but this study shows it can lead to deficiencies that hurt the bottom line. Blackmer says a simple solution is delaying fertilization until late May or early June.He says if farmers delay the application, they can get by with using less nitrogen and can be confident the plants will be able to use most of what they apply. Blackmer says it’s a win-win situation for farmers and the environment, and he says most farmers will likely adopt the later fertilizer application after they realize the benefits it can bring.