The interest in cover crops among farmers and landowners continues to increase each year due to the water quality and soil health benefits cover crops provide. Cover crops are an important tool in the Iowa Nutrient Reduction Strategy for their ability to reduce nitrate leaching and phosphorus loss through erosion. To increase cover crop adoption and reach the conservative NRS goal of cover crops on 20% of row crops acres (about four million acres), the economic value of retaining soil and soil nutrients also needs to be considered.
A recent study conducted by the Iowa Cover Crop Working Group explored the economic benefit of cover crops in retaining soil, soil nutrients and overall land value to the landowner. The study used RUSLE2 to generate soil loss estimates for 20 Iowa counties with and without cover crops. The results were then combined with cost of soil erosion to the landowner and nutrient value estimates.
Adding together the average value of soil loss due to erosion ($0.49) and the lost nutrient value ($5.57), the estimate per ton of soil is $6.06. For each ton of soil that is kept in place through conservation practices such as cover crops, $6.06 can be credited to that practice and help offset the cost of implementation.
The study was funded by the Iowa Department of Agriculture and Land Stewardship- State Soil Conservation Committee and the Leopold Center for Sustainable Agriculture in partnership with the Iowa Learning Farms, Iowa State University, and Practical Farmers of Iowa.