Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn
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Nitrogen (N) is typically one of the largest corn fertilization expenses. Nitrogen application is critical because it signiﬁcantly improves corn yield in many crop rotations. When choosing N rates, producers need to carefully consider both achieving most proﬁtable economic return and advancing environmental stewardship.
In 2004, university agronomists from the Corn Belt states began discussions regarding N rate use for corn production. The reasons for the discussions centered on apparent differences in methods for determining N rates across states, misperceptions regarding N rate guidelines, and concerns about application rates as corn yields have climbed to historic levels. An outcome of those discussions was an effort with the objectives to:
▪ develop N rate guidelines that could be applicable on a regional basis and
▪ identify the most proﬁtable fertilizer N rates for corn production across the Corn Belt.
This publication provides an overview of corn N fertilization in regard to rate of application, investigates concepts for determining economic application rates, and describes a suggested regional approach for developing corn N rate guidelines directly from recent research data.
Agriculture | Agronomy and Crop Sciences
Sawyer, John; Nafziger, Emerson; Randall, Gyles; Bundy, Larry; Rehm, George; and Joern, Brad, "Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn" (2006). Extension and Outreach Publications. 105.
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