The primary goal of FRST is to increase soil testing transparency by promoting clear and consistent interpretations of fertilizer recommendations by removing political and institutional (public and private) bias from soil test interpretation and providing the best possible science in order to enhance end-user adoption of nutrient management recommendations. A secondary goal is to provide a catalyst for innovation in soil fertility – useful to those making recommendations as well as those evaluating those recommendations.

Provide information that can be used to augment (not replace) existing state recommendation systems.


  1. Identify the factors that inhibit end-user adoption of soil-test services for nutrient management.
    1. Survey land-grant institution soil-test-based recommendations to understand the complexity and variation of existing recommendations and provides a synthesis of results, which will be provided to the soil fertility and agricultural communities.
    2. Develop standardized terminology for use in soil-test-based nutrient management recommendations that enhance end-user understanding and adoption of soil testing.
  2. Establish minimum data requirements for legacy dataset inclusion and for future correlation-calibration studies in order to standardize best practice.
  3. Develop a database that provides a clearing house for soil fertility data that is populated with legacy and current data for soil-test correlation and calibration studies for major field crops grown in North America. The database should be:
    1. Accessible and queriable through the decision-support tool.
    2. Easy to use so that new data can be readily uploaded. The data should meet the minimum data requirements based on the protocol developed in objective 2.
  4. Develop a searchable, decision support tool that:
    1. Provides soil test correlation and calibration analysis output (graphs and statistical confidence intervals) based on queryable terms such as crop, multiple crops, soil-test method, soil sample depth, soil series, etc.
    2. Provides data for nutrient management researchers and modelers that allow for in-depth analysis of soil test calibration and correlation data.

Specific Functions and/or Uses of the Decision Support Tool and Database

  1. Perform correlation analysis that provides:
    1. relative yield  response curve across the range of soil-test values 
    2. predicted critical soil-test nutrient concentration and its standard error 
    3. for ranges of soil-test values (either preselected or end-user input)
      1. calculate the frequency of “significant” yield increase
      2. calculate the magnitude of yield increase from fertilization
      3. calculate the mean actual yields for the control treatment and the maximum yielding treatment
  2. Perform fertilizer-nutrient rate calibration analysis across the range of soil-test values showing confidence intervals
  3. Include a multiple regression equation option that combines the correlation and calibration steps. 
  4. Use meta-analysis to identify:
    1. physiographic regions that can share data-driven, soil-test recommendation logic.
    2. gaps in research data and soil-test recommendation accuracy to guide future research and technology.