Nutrient Management: Apply Nutrients to Meet Realistic Yield Goals

alternative practice names:

Nitrogen levels in soil can readily fluctuate, given changing weather and soil conditions. Because nitrogen is highly dynamic in the soil, directly measuring it can be challenging. Therefore, application rates are often based on estimated crop uptake, past performance, and yield goals, supplemented by soil tests and models. Determining the correct rate of nitrogen fertilizer for your crop involves setting a realistic yield goal. Setting your yield goal too low can lead to under-fertilization, resulting in suboptimal crop performance. Conversely, setting your goal too high may cause over-fertilization, leading to increased costs, a higher risk of fertilizer loss to the environment, and decreased nutrient use efficiency.

The best way to set realistic yield goals is to collect yield data annually to accurately estimate yield potential. Yield data can be collected on various scales, from whole-field data using truck scales to georeferenced yield information using a yield monitor at harvest. Determining yield trends over time at whole farm and field levels will help assess the impact of changes in management on production and farm profitability. Due to the impact of weather-related variability, it is important to accumulate at least three or more years of yield information to have enough history to create accurate trends. This data can be used to set nutrient application rates across fields or to apply nutrients precisely within a field. Yield trends can guide future management decisions around not just fertilizer but variety selection, seeding rates, and irrigation needs.

REGIONALITY

When used, in what regions in the U.S. is the practice found:

Northwest, West, Upper Midwest, Southwest, Northeast, Southeast

FARM SIZE

When used, typically found on farms of the following sizes:

All Sizes

Practice Benefits

Optimized nutrient use efficiency: Applying only the nutrients needed to achieve realistic yield goals ensures that plants receive adequate nutrition without over-application, maximizing the efficiency of nutrient use and reducing waste.

Reduced input costs: By tailoring nutrient applications to realistic yield goals, farmers can avoid unnecessary fertilizer costs, leading to overall savings in input expenses.

Implementation Insights

Site-specific or Farm-specific requirements

Surplus manure: This practice is more challenging on farms with surplus manure nutrients.

Required Capital Expenditures (CapEx)

Yield measurement equipment: Farms will need a method to measure crop yields accurately. Options vary from low-cost solutions, like truck scales (calibrating trucks by weighing them empty and full), to more advanced systems, such as yield monitoring equipment with GIS software. The latter offers a comprehensive analysis of raw yield data but requires a higher investment.
Field record-keeping systems: To effectively track and manage nutrient applications, investments may be needed in record-keeping tools or software that allow for detailed field-by-field records. Consistent record-keeping helps track changes and trends to enable more informed decision-making, but it also requires an ongoing commitment to consistent data collection and management.
GIS and data analysis software: Farms opting for more precise yield monitoring can purchase and implement GIS software that analyzes spatial data to make informed nutrient management decisions based on field-specific yield information.

Required Operational Expenditures (OpEx)

Equipment calibration and maintenance: Yield monitoring equipment, truck scales, or other measurement tools should be regularly calibrated to ensure accuracy, which may involve service fees or maintenance costs.
Labor costs: Farms may incur additional labor expenses for collecting, recording, and analyzing yield data across fields and managing field-by-field records of nutrient applications, seed varieties, and crop performance. Certified Crop Advisors (CCAs) or crop consultants can help organize historical yield data and set realistic goals. Yield potential varies greatly by field, so understanding the nuances of each field is important for accurate goal setting.

Implementation Considerations

Adjusting for environmental factors: Calculating crop nutrient demands involves considering land productivity potential, weather conditions, and management practices. For instance, severe weather events like droughts or floods can affect multi-year averages, making it important to account for such anomalies when developing yield estimates. This underscores the need to be flexible and to adjust plans based on recent conditions rather than relying solely on historical averages.
Nitrogen management considerations: Nitrogen application rates are often adjusted to account for organic matter inputs from sources like leguminous cover crops, plowed-down hay, and manure applications. Using tools such as the Pre-Sidedress Nitrate Test (PSNT) can provide insights into residual nitrogen levels, while the Corn Stalk Nitrate Test (CSNT) prior to harvest offers a snapshot of nitrogen sufficiency.
Adapting to evolving nutrient recommendations: Nutrient management plans often need to evolve as soil fertility trends, crop performance, and environmental conditions change. Farmers may need to adjust strategies based on emerging patterns or unexpected variability in nutrient availability. Recognizing these complexities and being adaptable can help in developing a sustainable and effective nutrient management program.

Financial Considerations and Revenue Streams

FEDERAL COST-SHARE PROGRAM

Funding is available for this practice through USDA's Natural Resources Conservation Service (NRCS) Environmental Quality Incentives Program (EQIP).

Related EQIP Practice Standard: Nutrient Management (590).

Notes:

Check with the local NRCS office on payment rates and practice requirements relevant to your location.
A Nutrient Management Plan (NMP) may be required to receive implementation funding for this practice.

Additional Resources

Article: Setting Realistic Yield Goals (University of Nebraska-Lincoln)

Article: The 5 R's of Precision Agriculture (South Dakota State University)

Factsheet: Determining Yield Goals ((University of California-Davis)

Factsheet: Importance of Knowing Yields (Cornell University)

Factsheet: Setting Realistic Crop Yield Goals (University of Minnesota)

Environmental Impacts

REDUCES FARM GREENHOUSE GAS FOOTPRINT

Applying nitrogen based on realistic yield goals may reduce the use of commercial nitrogen fertilizer, thus reducing the greenhouse gases (GHGs) associated with commercial fertilizer production and transport. Additionally, when nitrogen is not overapplied, the risk of soil nitrous oxide emissions is also minimized.

See research highlights below:

Kim and Dale (2008) used a life cycle assessment and ecoefficiency analysis to study optimal N application rates. They found that increasing N can reduce GHG emissions by enhancing yield and soil C sequestration. Beyond a certain point, however, further increases in N application rates result in higher GHG emissions that outweigh the benefits of yield and soil C improvements.
Snyder et al. (2009) concluded in a review that precise management can help maintain soil organic carbon (SOC) levels, reduce residual soil NO₃, and minimize NO₂ emissions, though results vary depending on specific site and weather conditions.

IMPROVES WATER QUALITY

Estimating nitrogen contributions from residual soil organic nitrogen and other organic nitrogen sources, such as manure and legume crops, during nutrient planning allows farmers to better match crop nitrogen needs without over-application. This minimizes the risk of excess nitrogen leaching into groundwater or running off into surface water.

REFerences

Alignment with FARM Program

FARM Environmental Stewardship (ES) V2-V3 Alignment

FARM ES Version 2 and Version 3 ask if the farm has a nutrient management plan (NMP), if it is maintained and implemented. FARM ES Version 3 also includes an optional crop module, allowing users to enter their unique management practices including fertilizer and manure application.

Practice Overview