Introduction to the Nutrient Management Initiative

The Minnesota Nutrient Management Initiative (NMI) was developed to assist farmers and crop advisers in evaluating alternative nutrient management practices on their own fields. Participating farmers can work with a crop adviser to set up Field Trials or Advanced Rate Trials on their own farms. After submitting crop management information and completing trial harvest, farmers and crop advisers are reimbursed for their time and will receive a summary of the results of their trials.

Participating farmers are compensated $800 for a Field Trial and $1,000 for an Advanced Rate Trial.
Participating crop advisers are compensated $400 for each Field Trial and $500 for each Advanced Rate Trial. There is a one site maximum per farmer and ten sites maximum per adviser, funding permitting.

Results and information from these trials will help:

  1. Farmers and crop advisers evaluate current nutrient management practices versus another practice (nitrogen rate, nitrogen application timing, use of a nitrogen stabilizer product, or different nitrogen source) on their own farms.
  2. Provide an opportunity to compare different nutrient management practices and evaluate the outcomes of other trials.
  3. Assist participants in evaluating practices that will help reduce nitrate losses from their fields.
  4. Assist in highlighting existing advancements in nutrient management practices from farmers and crop advisers that can help demonstrate Best Management Practice (BMP) adoption in Minnesota.
  5. Inform the University of Minnesota’s current nitrogen fertilizer recommendations (Advanced Rate Trials).

Individual results will be kept strictly confidential. Statewide results will be summarized for outreach purposes only to help highlight existing farm practice and Ag industry advancements in nutrient management.

  • The Minnesota NMI program is available statewide.

  • To enroll, farmers and crop advisers should both complete the simple registration form online, or contact a local NMI representative by March 15 (Farmers are limited to one Field Trial or Advanced Rate Trial, crop advisers are limited to ten).

  • Farmers may work with a Crop Adviser or Co-op Agronomist to set up a Field Trial and record and submit required documentation.

    • If a farmer does not have a crop adviser, the MDA staff will be able to assist with Field Trial set up, harvest, and completion of required forms.

    • Crop adviser will verify information is correct by submitting forms for the farmer.

  • Farmers can work with a Crop Adviser or MDA representative to set up Advanced Rate Trials and record and submit required documentation.

  • Individual identity and locations from the NMI program will be kept confidential and only used for year-end summaries and educational or promotional purposes.

Farmer Payment

The State grant agreement is written to compensate farmers in two payments. A fully executed grant agreement must be in place prior to starting the trial. (Note compensation is different for Advanced Rate Trials):

  • Payment 1 for a Field Trial: $400 upon installing the Field Trial, completing and submitting the Crop Management Information Form by June 30.

  • Payment 2 for a Field Trial: $400 upon completing the Field Trial harvest, recording harvest results, and submitting the Harvest Information Form by December 31.

  • Payment 1 for an Advanced Rate Trial: $500 upon installing the Advanced Rate Trial, completing and submitting the Crop Management Information Form and as-applied fertilizer shapefile by June 30.

  • Payment 2 for an Advanced Rate Trial: $500 upon completing the Advanced Rate Trial harvest and submitting the yield monitor data shapefile by December 31.

Crop Adviser Payment*

The State grant agreement is written to compensate farmers in two payments. A fully executed grant agreement must be in place prior to starting the field trial. (Note compensation is different for Advanced Rate Trials):

  • Payment 1 for a Field Trial: $200 after assisting farmer(s) in installing the Field Trial, completing and submitting the Crop Management Information Form(s) by June 30.

  • Payment 2 for a Field Trial: $200 after assisting farmer(s) in the completion of the Field Trial harvest, recording harvest results and submitting the Harvest Information Form(s) December 31.

  • Payment 1 for an Advanced Rate Trial: $250 after assisting the farmer(s) in installing the Advanced Rate Trial, completing and submitting Crop Management Information Form(s), and providing as-applied nitrogen rate shapefiles by June 30.

  • Payment 2 for an Advanced Rate Trial: $250 after assisting farmer(s) in the completion of the Advanced Rate Trial harvest, recording harvest results, and submitting yield monitor data shapefile by December 31.

*Compensation is for participation only. The MDA makes no other guarantees for economic losses as a result of participating with this demonstration project. Failure to meet all timeline requirements will void payment.

Trial Establishment and Harvest Data Collection

  • Except for the management variable being tested, all other management practices should remain constant across the field (consistent nutrient application timing and method except where noted, hybrid, planting date, planting population, pest management, tillage, field history).

  • Keep detailed records for all field operations associated with trial area.

  • If field operations are performed by someone other than the participating farmer (custom applicator, co-op), operations must be performed according to established NMI guidelines and verified by participating farmer and crop adviser.

  • Tillage and planting operations should be performed under optimum soil conditions while ensuring that all equipment is calibrated and in good working order.

  • Collect accurate crop management and harvest data and ensure information is submitted in a timely manner.

  • For Field Trial: If GPS equipment is not available, delineate Field Trial strips prior to nutrient application, identify and reference Field Trial area on an appropriate field map (aerial map, FSA map). The MDA representative can also assist in Field Trial strip delineation if needed with a hand-held GPS unit.

  • For Advanced Rate Trial: Variable Rate Technology (VRT) and yield monitors to aid in Advanced Rate Trial design, installation and harvest are required.

  • Alert the MDA representative of any issues that may impact successful plot harvest (hail, drought, flooding, wind).

Assist Farmer with Trial Establishment

  • Help farmer(s) establish their trial in participating field(s), following NMI guidelines.
  • Validate all field trial locations with flags, markers, or other means that are identifiable at time of harvest. GPS coordinates of each strip within the Field Trial are desirable, they are required for Advanced Rate Trials. 
  • Submit Crop Management Information Form to an NMI representative by June 30 using the provided forms. Submitting form verifies adviser has reviewed for accuracy and the trial was set up correctly.

Assist Farmer with Harvest Data Collection

  • Provide field trial layout maps or GIS shapefiles (if not previously provided).

  • Be present at harvest. Verify and document yield according to established guidelines.

  • Validate trial locations and record yield data accordingly.

  • Ensure all weighing/monitoring equipment (weigh wagon, yield monitor, grain cart) is properly calibrated prior to trial harvest.

  • Ensure combine separator and grain tank are empty prior to and after harvesting each strip within the Field Trial if using a weigh wagon or grain cart.

  • Determine grain weight using same weighing/monitoring equipment (weigh wagon, yield monitor, grain cart) for each strip within the trial.

  • Collect and record yield, moisture, and test weight information for each strip within the trial.

  • Adjust grain yield to 15% moisture using formula provided in the Harvest Guidelines.

  • Evaluate crop stand and record any issues on Crop Management and Harvest Information Forms.

  • Complete Harvest Data Form and submit to an NMI representative by December 31 using the provided forms. In case of delayed harvest or any other issues, contact area NMI representative.

  • Previous Crops:

    • For Field Trials: Previous crops can be corn, corn silage, soybeans, wheat, oats, small grains, sugar beets, potatoes, dry beans, or canning crops. Alfalfa acres are eligible but appropriate stand count and nitrogen credits should be accounted for on Crop Management Information form. Cover crops following cash crop are eligible as long as seeding rates, dates, and species are documented on Crop Management Form.

    • For Advanced Rate Trials: Previous crops must be corn or soybean, must have corn-corn or corn-soybean rotation history.

  • Fertile soils are preferred. Ideally, current soil test P levels should be >16 ppm (12 ppm Olson) and current soil test K levels should be > 121 ppm.

    • Complete a soil test from a Certified Laboratory.

    • Soil test must be current or within the past two growing seasons and must be representative of Field Trial location.

  • Trial sites with fairly uniform terrain and straight rows are preferred.

  • Field uniformity is desirable. The field can have variability of soil type and topography as long as the variability goes perpendicular to the rows.

  • Avoid areas that have slopes, irregular boundaries, or variable field history.

Criteria for Field Trials:

  • Compare the normal practice to a trial practice

  • Including a check strip with zero pounds nitrogen applied is preferred but not required.

    • A check strip is a useful tool that allows a general consideration for the field and variety response to additional nitrogen and soil mineralization potential to be considered on each Field Trial site.

    • Check strip size should be 200 feet long and located directly adjacent to the Field Trial area.

    • Ammoniated phosphorous contributions or low nitrogen rates from another nutrient application (starter, incidental nitrogen, weed and feed) are allowed on check strips, but should be noted on the Crop Management Information Form. One width of application equipment required for check strip as long as it is wider than harvest equipment.

  • Field length strips preferred, minimum of 30 feet wide by 600 feet in length and strips that span the entire length of the field are preferred and generally allow for easier application and harvest.

  • Corn grown and harvested for grain only

  • Each Field Trial should only have one variable. Keep all other factors consistent across Field Trial area (hybrid/variety, other nutrients, rates, pest management, soils, tillage operations, field history, drainage, topography, equipment, and other variables).

  • Crop adviser submits information to verify accuracy (If a farmer does not have a crop adviser, please contact closest NMI representative for assistance.)

  • Alternating treatments across field are accepted. For best results randomizing Field Trial strips is recommended. Contact area representative for assistance.

  • Width of individual strips within the Field Trial must be consistent with fertilizer application and harvest equipment. Larger field blocks are recommended if replications are not possible.

  • All nitrogen sources (MAP, DAP, starter) must be accounted for in final nitrogen application rate.

    • Exception: Variable rate applications of phosphorus and potassium are allowed. Account for nitrogen contributions from ammoniated phosphorous by averaging application rates within the Field Trial area.

  • All fertilizer applications must be applied using properly calibrated equipment.

  • Nutrient application rates determined and verified by farmer and crop adviser

Field Trial Examples and Additional Criteria

Criteria For Advanced Rate Trials

  • Corn grown and harvested for grain only

  • Each trial should only have a nitrogen rate variable. Keep all other factors consistent across the Advanced Rate Trial area (hybrid/variety, other nutrients, rates, pest management, soils, tillage operations, field history, drainage, topography, equipment, and other variables).

  • Crop adviser submits information and GIS shapefiles of as-applied and yield monitor data to verify accuracy

  • All nitrogen sources (MAP, DAP, starter, etc) must be accounted for in final nitrogen application rate.

    • Exception: Variable rate applications of phosphorus and potassium are allowed. Account for nitrogen contributions from ammoniated phosphorous by averaging application rates within the Advanced Rate Trial area.

  • All fertilizer applications must be applied using properly calibrated equipment.

  • Nutrient application rates determined and verified by farmer and crop adviser

  • Must have corn-corn or corn-soybean rotation history

  • No manure or alfalfa history in the last 5 years

  • Nitrogen rate test strips contain 5-6 unique N rates and each N rate replicated 3 times

  • 40-50 lb difference between N rates

  • Must include zero rate check strip (check strip can only include N contributions from DAP or MAP applications and must be under 50 lbs of N prior to applying nitrogen rate prescription)

  • Soil types, topography, drainage, and field history should be consistent across the trial area

  • Variable rate technology (VRT) and yield monitors to aid in Advanced Rate Trial design, installation, and harvest

  • Yield and moisture information collected and recorded by yield monitor of the trial area (submit yield monitor data along with any other yield information when available).

  • Harvest only after crop has reached physiological maturity (black layer).

  • Each trial should be harvested using the same equipment.

  • Avoid harvesting areas within individual trial strips with variable harvest populations (missing rows, cultivator blight, wind damage, insect damage).

  • Do not harvest areas where nutrient applications do not match crop rows.

  • Grain weight determined using calibrated weighing equipment (yield monitor, grain cart scale, weigh wagon).

Harvesting Individual Trial Strips

  • Ensure yield monitor is calibrated and calibration does not change during harvest of all strips.

  • Zero out weight before harvesting each strip.

  • Record yield monitor total weight from each strip.

  • Ensure combine separator and header are thoroughly cleaned after harvesting each strip.

  • Manually test the moisture of the grain harvested from each strip.

  • If applicable, estimate lodging when harvesting each strip and document on Harvest Information Form.

  • Do not include overlap rows or wedge rows when collecting results.

** Grain moisture taken and corn grain yields adjusted to 15% moisture (included in Harvest Information Form).

Corn Grain Yield Formula—Conversion to 15% moisture:

Grain Yield = (100 – moisture) x (lb of grain) x (109.815) / (Row Length in feet) / (Row width in inches) / (Number of Rows).