The Tri-State Fertilizer Recommendations for Corn, Soybeans, Wheat, and Alfalfa was first published in 1995 and has served as a cornerstone in nutrient management in field crops for Indiana, Michigan, and Ohio. As crop production practices in this region changed over the past 25 years, many questioned if these nutrient management guidelines were still relevant today.
In 2014, work began to revise and update the nutrient management recommendations in corn, soybeans and wheat. Over 300 on-farm trials were conducted across 34 Ohio counties, including trials evaluating crop response to N, P, K, and S. It was a tremendous collective effort with the ultimate goal of providing objective information to farmers to manage nutrients as judiciously and profitably as possible.
The recommendations have been comprehensively revised and updated. A summarized version can be found online: go.osu.edu/fert-recs
The full version of the recommendations is being finalized at OSU Extension Publishing and a downloadable pdf and printed bulletin will be available soon.