Calculator

OSU Agronomist Donald Horneck at AG CONNECT

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Dr. Donald Horneck of Oregon State University shares the latest research on controlling nitrogen loss in irrigated fields.

Research Background

"Development and Use of the OSU Organic Fertilizer and Cover Crop Calculator". N. Andrews, D.M. Sullivan, J.W. Julian and K.E. Pool. 2011

"Predicting Plant-Available Nitrogen Release From Cover Crop Residues". Dan M. Sullivan, Ronjon Datta, Nick Andrews, and Kristin E. Pool. 2011

"Estimating Plant-Available Nitrogen Release from Manures, Composts, and Specialty Products". Eric S. Gale, Dan M. Sullivan, Craig G. Cogger, Andy I. Bary, Delbert D. Hemphill, and Elizabeth A. Myhre. 2006

"Estimating N contribution from organic fertilizers and cover crop residues using online Calculators". Dan M. Sullivan and Nick A. Andrews, John M. Luna, and John P.G. McQueen. 2010

OSU Organic Fertilizer and Cover Crop Calculator

Download the OSU Calculator

This Excel spreadsheet estimates nitrogen release from organic fertilizers and cover crops, and calculates costs. You can download calculators for per acre or per 1000sf calculations. Developed by Nick Andrews, Dan Sullivan, Jim Julian and Kristin Pool.

Information and resources


This work was sponsored by Western Sustainable Agriculture Research and Education (projects FW06-301 and FW09-328), Oregon Tilth, Inc. and the OSU Oregon Organic Cropping Research program.

We also thank Stutzman Environmental Products, Concentrates Inc., Wilbur-Ellis Company, and Bridgewell Resources for supporting this work with their donations.