Nutrient Management: Precision Nutrient Application
alternative practice names:
Precision Agriculture; Variable Rate Application
Precision nutrient management relies on detailed data about soil properties, crop growth, and yield history to inform nutrient management. In-field differences in soil type, topography, drainage, and previous management practices can cause significant variability in nutrient needs across the field. Applying a uniform rate of fertilizer across an entire field can lead to inefficiencies, such as overapplication in some areas and underapplication in others.
Using soil samples collected in a grid or zone pattern across the field and technologies like sensors and imagery, precision nutrient management helps assess the nutrient needs of crops throughout the field. This information is used to create a variable rate nutrient management prescription. This is a field-scale map specifying how much lime, phosphorus, potassium, nitrogen, and other nutrients should be applied across the different grids or management zones.
Equipment with Variable Rate Technology (VRT) utilizes GPS technology to apply nutrients according to a detailed prescription map. Prescription maps can be created using two different methods:
Real-time variable nutrient application rates: In some cases, this occurs in real-time as electrical conductivity (EC) sensors read soil chemical characteristics and instantly adapt to the nutrient application.
Pre-determined variable nutrient application rates: Alternatively, nutrient application rates can be informed by maps generated from previous soil testing, satellite imagery, or yield history.
Variable rate technology is commonly available on fertilizer spreaders and applicators, planters applying fertilizer in or near the seed trench, and sprayers. The most common nutrients applied via variable rate or precision nutrient application include nitrogen and potassium, along with lime.
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
Cost savings: Precision nutrient management reduces the overuse of these inputs and/or higher rates of return for money spent on inputs by applying fertilizers only where needed and in precise amounts.
Enhanced crop yields: Precision nutrient management can also help ensure each part of the field receives the precise amount of nutrients needed, optimizing plant health and growth conditions for maximum yield potential.

Implementation Insights
Site-specific or Farm-specific requirements

Field variability: This technology is more applicable to fields with a lot of variability, such as fields where soil characteristics, such as drainage class, differ significantly across the field, fields with varying slopes, and fields with treelines and uneven shapes where shading may impact yield potentials.
Required Capital Expenditures (CapEx)

GPS guidance: To implement precision nutrient management, farms will need GPS guidance systems on equipment to ensure efficiency and precision. GPS guidance minimizes the overlap between equipment passes, which helps reduce wasted inputs like seeds, fertilizers, and pesticides and allows farms to apply inputs more accurately, optimizing crop growth and reducing the potential for runoff or environmental impact. There are two main categories of guidance products:
Lightbar/visual guidance: In this system, the operator receives visual cues based on GPS positional information to manually steer the equipment, following the lightbar’s directional guidance.
Auto-guidance: This system is more advanced, allowing for semi-automated steering. The operator makes the initial steering and aligns the equipment for the next pass before engaging the auto-guidance mechanism, which then takes over to steer the equipment accurately along the set path.
Variable rate technology (VRT): VRT systems measure and place inputs such as fertilizers, pesticides, and seeds based on the specific needs of different field zones. These systems include a combination of sensors, controllers, and agricultural machinery designed to apply varying rates of crop inputs at precise locations and times. The investment in VRT can be substantial due to the need for specialized equipment that integrates with sensors and data controllers.
Automatic section control: Automatic section control systems seamlessly turn off application equipment when entering previously covered areas or when navigating headlands, terraces, point rows, and designated no-spray zones like grass waterways. They are often integrated into boom sprayers, planters, and individual nozzle or row units. These systems can be retrofitted on existing equipment.
Crop sensors: Crop sensors collect real-time data on crop health and status; They typically measure NDVI (Normalized Difference Vegetative Index) to assess crop vigor, predict yield potential, and provide relative biomass measurements. The data collected guides variable-rate nitrogen applications and other crop management practices. The technology requires on-the-go optical sensors, LED light sources, and software for data analysis and integration with other precision systems.
Yield monitoring/mapping systems: Yield monitoring devices installed on harvest machinery provide real-time data on moisture content and field productivity. These systems are common on grain combines but less common on silage choppers/harvesters. The data can be used to inform nutrient application rates and identify high- and low-yielding areas.
Required Operational Expenditures (OpEx)

Labor: Additional labor is required for soil sampling, creating prescriptions, and managing spatial data. The detailed nature of precision nutrient management means more time is spent on field data collection, analysis, and implementation. Higher annual fees may be incurred when working with Certified Crop Advisors (CCAs) or agronomists due to the increased level of expertise and detail required for precision prescriptions and nutrient management planning.
Equipment rental or custom application fees: If the farm does not own the necessary equipment for precision nutrient application, rental costs or fees for hiring custom applicators may be incurred. Custom applicators may use specialized equipment capable of applying variable rates of nutrients according to prescriptions, but these services come at an additional cost.
Implementation Considerations

Data management and Interpretation: Precision nutrient application relies heavily on the collection, analysis, and interpretation of spatial data, such as soil maps, yield maps, and crop sensors. Managing and accurately processing this data requires advanced software tools and technical knowledge. Farmers must often invest time and resources into learning how to operate these systems effectively or hire experts.
Equipment compatibility and integration: Implementing precision nutrient application requires the integration of various technologies, including GPS guidance systems, variable rate technology (VRT) equipment, crop sensors, and yield monitors. Ensuring compatibility between different systems and integrating them into existing machinery can be complex and may require upgrades or retrofitting of older equipment.
Soil and crop variability: Precision nutrient management must account for spatial variability in soil properties and crop conditions across a field. Accurately sampling soils and understanding the variations within a field is critical but labor-intensive. Inadequate or improper soil sampling can lead to inaccurate prescriptions and ineffective nutrient applications, reducing the benefits of the technology.
Financial Considerations and Revenue Streams
FEDERAL COST-SHARE PROGRAM
Funding is available for this practice through USDA's Natural Resources Conservation Service (NRCS) Conservation Stewardship Program (CSP).
Related CSP Enhancement: Reducing risks of nutrient loss to surface water by utilizing precision agriculture technologies (E590B).
Notes:
Check with the local NRCS office on payment rates and practice requirements relevant to your location.
FINANCIAL RESOURCES, TOOLS, AND CASE STUDIES
Additional Resources

Environmental Impacts
REDUCES FARM GREENHOUSE GAS FOOTPRINT
By using data to inform nutrient application and match nitrogen application, farmers avoid overapplying nitrogen to parts of the field. Preventing the overapplication of nitrogen reduces the release of nitrous oxide from agricultural soils.
See research highlights below:
Kazlauskas et al. (2021) found that VRF reduced the overall use of N, P, and K fertilizers by nearly 25%, decreased energy consumption and greenhouse gas emissions, and lowered total production costs compared to fixed-rate fertilization.
IMPROVES WATER QUALITY
Matching crop nitrogen needs with natural nitrogen sources reduces the risk of excess nitrogen entering water bodies, improving water quality.
REFerences
Raza, I., Zubair, M., Zaib, M., Khalil, M. H., Haidar, A., Sikandar, A., Abbas, M. Q., Javed, A., Liaqat, M. M., Ain, A. T., Nafees, M., & Ashfaq, M. A. (2023). Precision nutrient application techniques to improve soil fertility and crop yield: A review with future prospect. International Research Journal of Education and Technology, 5(8), 109-123.

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.
Contents
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
Precision nutrient management relies on detailed data about soil properties, crop growth, and yield history to inform nutrient management. In-field differences in soil type, topography, drainage, and previous management practices can cause significant variability in nutrient needs across the field. Applying a uniform rate of fertilizer across an entire field can lead to inefficiencies, such as overapplication in some areas and underapplication in others.
Using soil samples collected in a grid or zone pattern across the field and technologies like sensors and imagery, precision nutrient management helps assess the nutrient needs of crops throughout the field. This information is used to create a variable rate nutrient management prescription. This is a field-scale map specifying how much lime, phosphorus, potassium, nitrogen, and other nutrients should be applied across the different grids or management zones.
Equipment with Variable Rate Technology (VRT) utilizes GPS technology to apply nutrients according to a detailed prescription map. Prescription maps can be created using two different methods:
Real-time variable nutrient application rates: In some cases, this occurs in real-time as electrical conductivity (EC) sensors read soil chemical characteristics and instantly adapt to the nutrient application.
Pre-determined variable nutrient application rates: Alternatively, nutrient application rates can be informed by maps generated from previous soil testing, satellite imagery, or yield history.
Variable rate technology is commonly available on fertilizer spreaders and applicators, planters applying fertilizer in or near the seed trench, and sprayers. The most common nutrients applied via variable rate or precision nutrient application include nitrogen and potassium, along with lime.
Practices and technologies
Nutrient Management: Precision Nutrient Application
alternative practice name:
Precision Agriculture; Variable Rate Application