Iowa Farm Bureau Federation
12/09/2024 | News release | Distributed by Public on 12/09/2024 09:59
Record year for conservation in Iowa
Survey shows that cover crop acreage in Iowa has more than doubled in the past seven years to 3.84 million acres in 2023.
2024 has been a record year for conservation in Iowa as farmers expand adoption of practices that protect and improve soil health and water quality.
Iowa farmers lead the nation in various in-field and edge-of-field conservation practices, including buffers, waterways, filter strips, conservation tillage, water quality wetlands and pollinator habitat, according to data from the U.S. Department of Agriculture.
In addition, the Iowa Department of Agriculture and Land Stewardship reports that 2024 is on track to be a record year for progress toward the construction of water-quality wetlands in Iowa with 29 projects under development.
Also, a new survey of ag retailers shows Iowa farmers are planting more cover crops than ever while also increasing adoption of other practices including reduced tillage and nutrient management.
"Iowa farmers have been a consistent leader in efforts to improve productivity and enhance sustainability," said Iowa Farm Bureau President Brent Johnson.
"Farming is a marathon, not a sprint. The research and data that has been collected over the years regarding new practices have given farmers more tools to choose from in their toolbox. We continually see more adoption as farmers identify the practices that work best for their topography."
The latest survey by the Iowa Nutrient Research and Education Council (INREC) shows that cover crop acreage in Iowa has more than doubled in the past seven years, rising from 1.6 million acres in 2017 to 3.84 million acres in 2023.
Iowa farmers are now planting cover crops on 17% of their corn and soybean acres, according to the survey. Rye remains the top choice for cover crop plantings, accounting for 86.6% of cover crop acres in 2023.
Cover crops offer multiple benefits by keeping the soil covered between growing seasons to reduce erosion, absorb nutrients, suppress weeds and improve soil health. Iowa State University research shows cover crops can reduce soil nitrogen and phosphorus losses by 30% or more.
The INREC survey also found that conservation tillage practices, including no-till and strip till, continue to outpace conventional tillage by a wide margin. On average since 2017, 69.5% of Iowa's farmland is managed with conservation tillage or no-till, reducing soil erosion and promoting healthier soils.
The adoption of precision nitrogen-use technologies is also helping farmers reduce fertilizer inputs while maintaining yields. The INREC survey shows that a majority of farmers, averaging more than 59%, apply nitrogen only in the spring or in-season when it can be quickly utilized by growing crops.
Farmers also reduced commercial nitrogen applications in 2023 to an average of 166.6 pounds per acre in a corn-soybean rotation, marking a nearly 10% reduction compared to 2020.
Soil testing plays an important role in helping farmers determine how much fertilizer their crops need, with more than 80% of farmers utilizing soil tests for phosphorus.
Gaining efficiency
The effects of the conservation practices and other efficiency gains are impressive. Analysis shows the five-year average carbon intensity (CI) score for a bushel of corn in Iowa is down 46% since the 1978 peak.
Additionally, with cover crop effects considered along with reduced tillage and manure application, the five-year average CI score for 1 bushel of corn in Iowa is down even further, at 54% lower since the peak.
"These tremendous efficiency gains from better yields and corresponding reductions in fuel and fertilizer use per bushel of corn demonstrate the positive results these voluntary practices are having on reducing carbon intensity," said Christopher Pudenz, Iowa Farm Bureau economics and research manager. "It's an absolutely fantastic story of innovation and sustainability."
Five-year rolling averages are a good way to view longer-term trends in CI scores due to year-to-year weather variations that impact yields, Pudenz said.
A CI score represents a model estimate for greenhouse gas emissions associated with producing 1 bushel of corn based on several variables, including yields, the use of cover crops, manure and fertilizer, and tillage practices.
The calculation is gaining increased relevance for farmers due to various public and private programs that offer financial incentives based on a crop's CI score.
"A lot of the recent noise in regard to sustainability in agriculture has been focused on CI scores. Models demonstrate farmers have already made tremendous progress over the years," said Pudenz.
"They have made that progress because there was an economic incentive to do so. Farmers want to be good stewards, and they also want to be more efficient because it's a good financial practice."