One such practice is using a nitrification inhibitor when applying nitrogen fertilizer, which helps protect nitrogen from leaching below the root zone until the crop can use it. Farmers are often reluctant to use nitrification inhibitors since they add to the cost of production, and only increase yield or protect from nitrate loss with specific combinations of soil type and climate such as a warm, wet spring and sandy soils.
Recent research in the central Platte river valley of Nebraska investigated a promising new option for producers growing irrigated corn in environmentally sensitive areas, according to Richard Ferguson, professor of agronomy, University of Nebraska.
The study, conducted from 1995-1998, explored ways to reduce nitrate leaching to groundwater. Results from the study are published in the May/June issue of the Soil Science Society of America Journal, published by the Soil Science Society of America. Co-authors are Murray Lark, Silsoe Research Institute, Great Britain; and Glen Slater, University of Nebraska.
Using information about soil properties obtained from grid soil sampling, along with maps of crop yield and soil electrical conductivity, these researchers developed management zones to direct the application of nitrification inhibitors.
In relatively dry-to-normal growing seasons, the use of a nitrification inhibitor had no effect on grain yield or nitrate leaching. However, in a growing season with a very wet spring, the use of a nitrification inhibitor increased yield. Patterns of higher and lower yield in the wet growing season corresponded closely to patterns of soil electrical conductivity.
Contact: Sara Uttech
American Society of Agronomy