Though nitrogen is an essential nutrient for crop and animal production, too much of it in rations or in fertilizer and manure applied to crops can increase losses to groundwater, surface water, and air. Commercial feeds and fertilizers are significant—and expensive—sources of nitrogen, making nitrogen management important to dairy producers and the public.
A new, interactive website, “Nitrogen Management on Dairy Farms,” can help. It’s the result of cooperative work by scientists with the Agricultural Research Service, Cornell University, and the University of Vermont. A USDA Fund for Rural America grant provided funding for the project.
ARS soil scientist Jack Meisinger, of the Environmental Management and Byproduct Utilization Laboratory in Beltsville, Maryland, helped develop the website.
“It is vital that information about nitrogen management be freely accessible to dairy farmers,” says Meisinger. “But it is equally important that they be given the tools to achieve good nitrogen management. The website is a way of providing that.”
The website contains 58 linked pages of mixed-media content covering management of crops and soils, feed storage, dairy herd nutrition, and manure use.
“It’s part tutorial, with interactive diagrams as a review of information, and contains quizzes as well,” says Cornell collaborator Quirine Ketterings. The website also provides detailed information on how to sample and test manure, soil, and crops. “A farmer needs to know how these factors are linked in the nitrogen cycle,” Ketterings says.
Information is also available on how to interpret test results and calculate how much plant-available nitrogen is in manure. Given the high cost of fertilizer, accounting for manure nitrogen can greatly improve farm profitability. A downloadable spreadsheet, called the “Manure Nutrient Calculator,” is provided as an example of a manure-crediting system used in New York State.
State and federal research on managing the fate and transport of nitrogen in animal manure is used to formulate best-management practices. Case studies illustrate how farms have made changes to reduce nutrient imbalances and losses by taking a whole-farm approach to nutrient management.
Jack Meisinger is with the USDA-ARS Environmental Management and Byproduct Utilization Laboratory, 10300 Baltimore Ave., Beltsville, MD 20705-2350; phone (301) 504-5276, fax (301) 504-5526.
"Website for Dairy Nitrogen Management" was published in the March 2007 issue of Agricultural Research magazine.