By Andi Anderson
A recent study from Iowa State University has found that the amount of nitrogen fertilizer needed to maximize corn production in the Midwest has steadily increased over the past 30 years.
The study, published in Nature Communications, analyzed past research and found that optimal nitrogen rates have risen by about 1.2% per year since 1991.
The researchers attribute this increase to two main factors—higher corn yields and more nitrogen loss due to wetter spring seasons. They noted that while the findings were surprising, they align with real-world farming trends.
Farmers across Iowa have reported increasing their nitrogen application rates over time.
Efficient nitrogen use is critical to reducing environmental impact. Experts stress the need for farmers to fine-tune their fertilizer application to balance yield, costs, and sustainability.
The Iowa Nitrogen Initiative has launched a tool called N-FACT, which provides customized nitrogen rate recommendations based on weather, soil, and crop data.
The study also examined different nitrogen application strategies, considering economic, agronomic, and environmental factors. It found that maximizing profit requires slightly less nitrogen than maximizing yield.
However, reducing fertilizer use to minimize environmental impact would lead to lower corn production, creating a difficult trade-off.
Despite these challenges, researchers believe that improvements in efficiency have slowed the rate of nitrogen increase. Farmers now use less nitrogen per bushel of corn than they did 30 years ago. Best practices like crop rotation, improved drainage, and precise fertilizer application help reduce nitrogen waste while maintaining yields.
As corn yields continue to rise, researchers expect nitrogen requirements to keep increasing. The study highlights the importance of ongoing research and technology to help farmers optimize fertilizer use while protecting the environment.
Photo Credit: iowa-state-university
Categories: Iowa, Sustainable Agriculture