Tracking nitrogen mineralization in Northwest Minnesota soils

Lindsay Peace

Additional research-based recommendations on nutrient management are critically needed to support increased corn production in Northwest Minnesota. This project will address how soil texture and soil moisture affect soil nitrogen availability and corn grain production. To meet this goal, we will establish replicated research plots at the Northwest Research & Outreach Center in Crookston, Minnesota. We will monitor nitrogen dynamics by collecting soil moisture readings and monitoring nitrogen mineralization across five N rates and two soil types. Findings from this project will help to inform and improve UMN’s nutrient management recommendations for corn in Northwest Minnesota.

Recent increases in corn production in Northwest Minnesota (NW MN) means that this region currently lags behind the rest of the state in terms of soil fertility recommendations. Additional corn fertility trials are critically needed to improve our ability to make recommendations for NW MN corn systems. With more farms adopting corn into their rotations in the coming decades, supporting growers with research-based recommendations will help promote both more profitable corn production systems and improved soil and water quality.

Preliminary data from corn trials on nitrogen rate conducted in NW MN indicate that corn production is less governed by nitrogen rate than soil moisture. Soil moisture is affected by two main factors: precipitation and soil texture. In turn, soil moisture is known to affect soil microbial processes governing nitrogen mineralization. This project aims to provide an improved understanding of the fundamental processes affecting the timing of nitrogen availability during the growing season. This will help inform both rate and timing aspects of soil fertility recommendations for NW MN corn growers.
The overall goal of this two-year project is to evaluate how soil moisture, soil texture, and nitrogen rate interact to influence N availability during the growing season.