Cover crop and no-till effects on soil health properties in Indiana

A growing concern of soil health and long-term sustainability has increased interest in no-till and cover crops in the Midwest. Some of the challenges with no-till in the Midwest can be higher soil moisture and lower soil temperatures at cash crop planting in the spring, planter adjustment issues, and lack of immediate economic benefit. Cover crops also have some of the same issues along with extra cost of seed and termination, mismanagement of cover crops, and lack of knowledge on the benefits and costs. This project was begun in order to quantify the effects of no-till and cover crops on soil chemical and physical properties and on some cash crop properties. There were seven sites in Indiana with treatments comparing cover crops to no cover crop controls, and one site with a tillage and cover crop comparison. Three of the sites were Purdue research farms and the other four were farmer cooperator fields. Measurements taken included cover crop biomass and nitrogen (N) concentration, soil nitrate-N (NO3-N) and ammonium-N (NH4-N) concentrations, soil aggregate stability, soil water retention, soil penetration resistance, corn stalk NO3-N concentration, and corn and soybean yield. Because this study only had one or two years of cover crop growth, many of the results were not significantly different between cover crop and no cover crop. The cover crops did take up N in the fall and spring which was reflected in lower soil NO3-N concentrations in the treatments with cover crops. There were not many differences in the soil physical properties and no differences in the cash crop properties. The main difference in soil physical properties were between no-till and conventional till treatments, with no-till having better aggregate stability and higher soil bulk density, and lower total porosity than the conventional treatment. Two years may not be enough time to demonstrate the cover crop effects on the soil and cash crop properties. More research and time is needed to quantify the effects of cover crops on soil health over the long term.