2024 October Stewardship Advocate

The Iowa Nutrient Research and Education Council (INREC) supports, monitors and reports on progress towards the Iowa Nutrient Reduction Strategy efforts through science-based solutions and collaboration across Iowa’s agricultural production systems. INREC was formed created in 2015 to measure progress to meet the goals of the strategy. Iowa Corn is one of the founding members of INREC and is one of four on the board of directors. The board president is Roger Zylstra, a long-time contributor and member of Iowa Corn Growers Association.   Each winter, the INREC team hits the road, surveying 150 ag retailer locations out of the 600 across Iowa. The selection process is randomized to ensure unbiased, accurate insights into how Iowa farmers and landowners are managing their land to reduce nutrient runoff. Here’s what they discovered this year as a result of the survey: 

COVER CROPS – Cover crop usage continues to increase year after year! Since the survey’s inception in 2017, cover crop acres have increased from 1,597,614 acres to 3,841,525 acres in 2023 — an average increase of 320,559 acres each year!    Rye continues to be the #1 choice for Iowa farmers and landowners in 2023, dominating the other cover crops with 86.6% of the acres planted in Iowa being rye. Remaining cover crops are 6.1% oats, 5.5% species mix and 1.7% of other cover crops.

TILLAGE – Conservation tillage and no-till methods continue to outpace conventional tillage. On average since 2017: 33.1% of farmers practice conservation tillage 36.4% of farmers practice no-till 32.9% of farmers practice conventional tillage.  This means 69.5% of Iowa’s farmland is managed with conservation tillage or no-till, reducing soil erosion and promoting healthier soils.

NITROGEN USAGE – Corn/Soybean Rotation: In 2023, farmers applied an average of 166.6 lbs./acre of commercial-only nitrogen—16.8 lbs./acre less than in 2020, marking a nearly 10% reduction in use.  Corn-on-Corn: In 2023, nitrogen rates averaged 185.7 lbs./acre, down 23.2 lbs./acre from 2020, translating to an 11% decrease. 

 While fertilizer prices may be influencing these shifts, the adoption of advanced nitrogen-use efficiency technologies is also playing a major role in helping farmers reduce inputs while maintaining yields.