Developing Whole-Farm Nutrient Management

Developing Whole-Farm Nutrient Management

Summary

This project proposes to:

1) Increase farmers’ awareness of the need to manage nutrient flows and to budget for soil organic matter;

2) Tap farmers’ knowledge and experience to develop and test a tool that optimizes nutrient distribution and organic matter budgeting on their farms;

3) Develop a farmer-friendly, practical and easy-to-use nutrient budgeting system and refine this system through farmers’ use and feedback; and

4) Publish, promote and make such a whole-farm tool widely available through the Natural Resources Conservation Service and Soil and Water Conservation Districts.

Closing nutrient cycles at the farm level has become a major challenge in the quest to achieve an agriculture that is sustainable for future generations. Chemical fertilizer in the form of anhydrous ammonia, for example, is the single most expensive input in agriculture today in terms of energy required to manufacture it. Yet drain tile monitors show up to 50 percent of such chemical fertilizers in some of the most widely used U.S. farming systems merely washes away.

To farm sustainably generally requires reducing mineral fertilizer inputs. This in turn means farmers must have an adequate supply of decaying organic matter in their soils to release nutrients, maintain soil structure and control soil-borne pathogens. Ensuring nutrients are put to optimal use and budgeting for organic matter on farmers together will help prevent pollution, preserve soil fertility, reduce damage to natural waters and safeguard fish, animal and human life. To effectively close nutrient flows, farmers need insight into how these flows work. This will help them adapt their management practices and still benefit from reduced chemical fertilizer costs. Some tools for monitoring nutrient flows have become available in recent years. Work is just beginning, however, to adapt them for on-farm use and to assist farmers in their management decisions to effectively cut excess nutrients and budget for organic matter.

In this project, 20 farms each in Illinois and Wisconsin (40 total) will be assessed for nitrogen, potassium and phosphorous on an input/output basis. Six farms that show nutrient imbalances will be identified and selected from each of these groups. The other 14 farms in each state (28 total) will be invited to attend field days and training sessions, kept informed of the project, and encouraged to use management tools being used, refined and studied in this project. The six farms in each state (12 total) to be closely monitored and compensated will represent an even number of livestock, cash grain and mixed farming operations of varying sizes.

NRCS staff in Rock County, Wisconsin, will help us locate farm cooperators in southern Wisconsin. SWCD staff in Boone County, Illinois, will work closely with the Michael Fields Agricultural Institute staff in East Troy, Wisconsin, to map Illinois and Wisconsin farmers’ nutrient inputs and outputs with a mineral accounting yardstick. This will allow for a linkage between nutrient flows and soil test values. Although the nutrient management yardstick will be used to track the overall environmental impact of these farms, it does not account for changes that occur on the field level. More sustainable practices, such as an improved soil organic matter management, can contribute to a reduced environmental pollution due to a buildup of soil fertility and retention of potential leachable nutrients. Based on the crop rotations of the 12 monitored farms in this project, we will estimate the impact of management practices on their organic matter in the long-run using the Organic Matter Budgeting System. Through these farmers’ use of the yardstick and budgeter and their feedback, a practical guidebook will be developed and distributed through the NRCS and SWCD.

For more information:
C.J. Koopmans
Michael Fields Agricultural Institute
W2493 Cty Rd ES
East Troy, WI 53120
414-642-3303
414-642-4028 (fax)
mfai@mfai.org

Collaborators: