Liquid Swine Manure Applied via Drag Hose as a Sidedress Source for Corn Production

Abstract

In Minnesota, liquid swine manure (LSM) is commonly applied in the fall, which can increase the risk for nitrogen (N) to leave the root zone before next season’s crop can utilize it. Increased precipitation, as recently experienced in Minnesota, exacerbates this problem resulting in a growing interest for in-season nutrient application. Liquid swine manure applied via dragline hose was tested as a sidedress source for corn (Zea Mays L.) production compared to anhydrous ammonia (AA) and urea ammonium nitrate (UAN). Variables measured included corn stand counts, grain yield, grain moisture, and plant N uptake as well as soil compaction and soil in-organic N content through the growing season and post-season. Additionally, a small-plot dragline hose study was conducted comparing two different corn hybrids to examine what stage corn can be dragged before reducing stand counts and yield. When applied at similar plant-available N (PAN) rates, LSM produced comparable grain yields as AA and UAN despite lower soil in-organic N levels 12 days after application. Application of N sources at the vegetative (V4) growth stage did not reduce stand counts compared to the control, except for the LSM treatment in 2019 due to wet field conditions. Furthermore, the application of sidedress treatments did not increase soil compaction to critical levels that might impede root growth at the soil surface. In the small-plot study, corn grain yields were reduced at the V5 growth stage, and further reduced at the V6 growth stage, for both hybrids. Sidedressing LSM via a dragline hose system at or before the V4 growth stage provides producers in Minnesota an additional window of opportunity to apply their manure and is a viable nutrient source for sidedressing corn.