Dec. 5, 2014
A federally funded climate initiative, that includes Iowa State University, has launched a new online decision support tool to help farmers and farm advisers manage the application of in-field nitrogen for maximizing crop yields and minimizing environmental damage.
The free tool, called “Corn Split N,” is available for use in Iowa, Illinois, Indiana, Missouri and Kansas. Corn Split N combines historical weather data and fieldwork conditions with economic considerations to determine the feasibility and profitability of completing a post-planting nitrogen application for corn production.
The tool was developed as part of “Useful to Usable,” or U2U, a USDA National Institute for Food and Agriculture-funded research and extension project designed to improve the resilience and profitability of farms in the Corn Belt amid a variable and changing climate. The project team includes 50 faculty, staff and students from nine north-central universities with expertise in applied climatology, crop modeling, agronomy, cybertechnology, agricultural economics and other social sciences.
Chad Hart, an Iowa State associate professor of economics and extension crop markets specialist, is the local project coordinator for the Corn Split N tool.
“Traditionally, farmers have applied nitrogen to the soil in a single pass either in the fall or in the spring before planting,” Hart said. “However, research has shown that by splitting the nitrogen over two intervals, applying it once in the fall or spring when the soil is not saturated and the temperature is between 50 and 32 degrees Fahrenheit, and then a second time when the plants are in the ground and in most need of it, will ultimately lead to better results. Less fertilizer will be needed overall and not as much will be lost in run off.”
Hart said that nitrogen management of corn includes many factors. One is the timing of the application, which varies depending on weather and soil conditions. Corn Split N tool’s historical climate data is designed to assist farmers pinpoint when nitrogen should be applied for best results.
Because the post-planting application must be done before the corn gets too tall, estimates of corn development stages based on location, selected planting date and the accumulated corn growing degree days for the year also are factored into the tool. Growing degree day accumulations and associated corn growth beyond the current day are estimated based on the historical 30-year (1981 to 2010) average degree day accumulation for a location.
Hart said the Corn Split N tool helps farmers quantify the costs and benefits under average, worst and best case scenarios when doing a post-planting nitrogen application, even taking into account two passes of ground equipment in the fields.
Farmers get customized results based on their planting and fertilization schedule, local costs and available equipment. A summarized fieldwork table and crop calendar also allow farmers to see how schedule adjustments might affect their ability to fertilize on time.
In 2015, the product will be expanded to seven additional north-central states: Wisconsin, Minnesota, South Dakota, North Dakota, Nebraska, Ohio and Michigan.