Refining Fertilizer Applications

Problem

How can farmers be more precise in applying fertilizer to corn fields with cover crops?

• Knowing how much fertilizer to apply is complicated by a lack of available tools to accurately predict the correct amount of nitrogen that is needed for crops in any given year.

Findings

Researchers developed a prototype for an online decision support tool that corn growers can use to adjust nitrogen fertilizer applications. The system uses measurements that farmers and agronomists can easily collect in the field to predict the nitrogen contributed by the soil and cover crops.

• The team calibrated their tool using a dataset of 73 observations from nine cover crop experiments conducted over a three-year period.

Impact

In the last decade, the wide use of cover crops in rotations with corn has resulted in reductions in both nutrient pollution and sedimentation. This nitrogen recommendation system is an important step toward refining fertilizer applications to meet cash crop demands.

• Reducing over-application of fertilizer minimizes nitrogen pollution of waterways and helps to boost farmers' bottom lines.

Research Credit

Team

• Charles White, Denise Finney, Armen Kemanian, Jason Kaye, Kathleen Arrington, John Spargo

Participating Departments

• Ecosystem Science and Management
• Plant Science

Partner

• Ursinus College

Competitive Funding

• USDA National Institutes of Food and Agriculture (NIFA) (Agriculture and Food Research Initiative [AFRI])
• USDA NIFA (Organic Agriculture Research & Extension Initiative [OREI])
• USDA NIFA (Sustainable Agricultural Systems [SAS])
• USDA Northeast Sustainable Agriculture Research and Education (NE SARE)
• USDA Natural Resources Conservation Service (NRCS) (Conservation Innovation Grants)
• National Fish and Wildlife Foundation

Federal and State Appropriations

• USDA NIFA Hatch Projects PEN04571 and PEN04600, Accession #1003346 and #1009362

Emerging Discoveries

More precise nitrogen recommendations for corn to help farmers, cut pollution

October 15, 2020

Researchers in Penn State's College of Agricultural Sciences have developed an important component of a new system that corn growers can use to adjust nitrogen fertilizer applications based on site-specific measurements of cover crops and soil organic matter.

Published Research

Modeling the contributions of nitrogen mineralization to yield of corn.

• White, C. M., Finney, D. M., Kemanian, A. R., & Kaye, J. P. (2021). Modeling the contributions of nitrogen mineralization to yield of corn. Agronomy Journal, 113(1), 490-503. https://doi.org/10.1002/agj2.20474