A Survey to Evaluate the Current Status of Land Grant University and State Department of Agriculture Soil Fertility Recommendations and Analytical Methods

INTRODUCTION
Soil fertility testing is an integral tool used in nutrient management planning, providing the information needed to determine where nutrients are required and how much to apply. Over the last several decades, a great deal of effort has been successfully invested in standardizing soil test methods in the U.S. Less progress has been made toward coordination of soil test correlation and calibration efforts and development of clear and consistent guidelines for interpreting soil test results used to make fertilizer recommendations. Research in support of soil test recommendations has been conducted mostly by land-grant universities with only limited interstate or regional coordination for interpreting and developing soil-test-based recommendations. One of the first steps in addressing the lack of regional coordination is a comprehensive assessment of knowledge and resources that exist in support of land grant university soil testing and fertility programs. The last known national survey of land-grant university soil fertility recommendations was published over 20 years ago (Voss, 1998). Since that time, new analytical methods have been adopted, recommendation frameworks have been refined, new regional partnerships have formed, and the allocation of resources has shifted.
In 2019, we began developing a survey to collect contemporary information from our land-grant university colleagues working in soil fertility. The goals of the survey were to gain a better understanding of the current status of soil testing across the U.S. to inform future collaborative efforts among states and regions, and to identify where opportunities exist to harmonize recommendation guidelines. The objectives were to collect information about state soil test recommendations, fertilization philosophy, analytical methods, and the provenance of correlation and calibration data that support soil-test-based recommendations.
METHODS
The survey was adapted from one conducted in 2018 for the Southern states for a meeting in Athens, GA (D. Osmond, personal communication, April 12, 2022), and expanded to include information relevant to other regions in the U.S. The survey was developed using Qualitrics Software (Qualtrics, Provo, UT). Input on questions and formatting were provided by soil fertility specialists across the U.S. Distribution of the survey was coordinated with regional soil test working groups and committees in February 2020. Over 60 responses from 48 states and Puerto Rico were received by the survey close in June 2020. Survey responses for each state were reviewed for consistency and correctness and organized into 17 topic-specific tables. These tables were re-distributed to survey participants for follow-up review and confirmation of provided information, totaling three years of data collection (2020-2022). Results from this survey will help guide future soil fertility work and cooperation across state lines.
REFERENCE
Voss, R. 1998. Fertility recommendations: past and present. Comm. Soil Sci. Plant Anal. 29(11-14):1429-1440. https://doi.org/10.1080/00103629809370040 
ACKNOWLEDGEMENTS
We would like to thank the individuals who completed and provided information for the survey as well as the members of the Fertilizer Recommendation Support Tool (FRST) project who helped to develop and give feedback on the survey questions and format. We would also like to thank our funders, USDA-NRCS (grant 69-3A75-17-45) and USDA-ARS (grant 58-8070-8-016).