After 25 years, the Tri-State Fertilizer Recommendations for Corn, Soybeans, Wheat, and Alfalfa has been comprehensively updated and is now available. The full version can be downloaded as a free pdf, or a printed copy can be purchased through the extension office or online at https://extensionpubs.osu.edu/search.php?search_query=974§ion=product
A summarized version of findings can be found here: go.osu.edu/fert-recs