DEVELOPING A NATIONAL SOIL TEST CORRELATION AND CALIBRATION DECISION SUPPORT SYSTEM: FRST

what: the modernizing fertilizer recommendations: fertilizer recommendation support tool, or 'frst', project aims todevelop a soil-test and crop-response-to-fertilization searchable web-based tool that provides more consistent, transparent, andscience-based decision support for nutrient recommendations across the usa for major crops, including but not limited to corn,cotton, grain sorghum, peanuts, soybean, and wheat.why: soil testing provides the backbone for nutrient management programs in modern, intensive agricultural productionsystems. most science-based soil fertility recommendation systems derive phosphorus (p) and potassium (k) fertilizer guidancefrom soil-test results. while soil testing has the common goal of determining where fertilizer is needed and how much to apply,soil testing laboratories in the usa differ in soil analytical methods, interpretative terminology, and philosophical approaches tofertilizer recommendations. these differences often result in different fertilizer recommendations among labs within and acrossstates, leading to end user confusion and reduced confidence in soil testing, which ultimately proves detrimental to applicationand educational efforts that encourage 4r nutrient stewardship.how: we are building a stable database of soil-test correlation and calibration trials from published literature, theses anddissertations, and state records. results from both short (single year), intermediate (2-6 years), and long-term (>6 years) trialsare included. as of may 2020, we have compiled data from over 900 soil test p or k correlation trials from 29 states; we haveover 100 additional studies not yet cataloged and more leads for additional data. this is a very collaborative project.initially the data were entered into an excel spreadsheet, but it now resides in sql server format. to aid in the collection ofdata, we are building an automatic data upload function and we will provide an excel template to colleagues for data collection.to ensure proper credit, original authors will receive attribution for their data contributions through dois. the database will becataloged by and accessible through the national agricultural library so that it is available by all and provides perpetuity of thisresource.we have started the next phase of the project - the development of a web-based, front-end platform that provides basic dataanalysis by end users to identify critical soil-test nutrient ranges (correlation) and potential sufficiency approach interpretationsfor nutrient rate calibration. this data analysis tool will allow interpretative analyses at various levels, segregated by userselectedfactors that could influence the correlation and calibration outcome (e.g. physiographic region, soil properties, croppingsystem, irrigation, and yield level).who: the frst effort is currently comprised of over 70 individuals from across the us; all have volunteered to be part of thisproject. there are 30 land-grant universities, one private university, nine ars scientists, two natural resources conservationservice personnel, two private not-for-profit individuals, and one state department of agriculture employee engaged in thisproject.