There has been increased interest in interseeding cover crops into corn. Cover cropping is a way to prevent soil erosion, maintain and/or improve soil nutrients, improve soil aggregation, prevent nutrient loss from runoff, and increase water retention. Such soil improvements can promote conditions that add resiliency to a crop, especially considering extreme weather patterns that may affect yields. Interseeding can be beneficial by providing year-round ground coverage and maximizing a short growing season by interseeding early to allow for full cover crop growth. It can be difficult to grow a successful cover crop, given other demands from a farm operation and weather limitations. One challenge that farmers face when trying to implement interseeding is establishing the cover crops into dense rows of corn. Shading by corn plants restricts cover crop growth especially as the season progresses. Traditionally, corn is planted in dense 30-in. rows to maximize yields and decrease weed pressure. In 2018 and 2019, Practical Farmers of Iowa has conducted on-farm research trials to study the effect of wide rows (60-inch) on grain corn yields and cover crop biomass. Cover crop biomass was significantly increased when planted into 60-in. corn, but results were mixed when it came to corn yields. Over half the farms saw reduced corn yields in 60-in. corn compared to 30-in. rows (Gailans, 2018, 2019). This innovative practice may be a viable solution for farmers, but research needs to be done in the Northeast to determine the impact of wide rows on corn silage yield and quality, cover crop biomass, and soil health. In 2020, the University of Vermont Extension Northwest Crops and Soils Program conducted the second year of this trial to examine the impact of corn row spacing and population on interseeded cover crop success, as well as corn yield and quality here in the Northeast.
Vermont, University of Vermont, cover crop, wide row corn
Darby, Heather; Krezinski, Ivy; Malone, Rory; and Ziegler, Sara, "Interseeding Cover Crops into Wide-Row Corn Silage" (2020). Northwest Crops & Soils Program. 397.