Does a Winter Rye Cover Crop Effect Soil Physical Structure?.

Upper Midwest agricultural systems are characterized by many problems that can jeopardize environmental sustainability, including heavy traffic and tillage, which slowly depreciate soil structural and physical properties. Cover cropping can provide an improved soil structure by adding soil organic matter and breaking apart large soil aggregates with their roots, which can improve drainage and enhance agronomic system sustainability. Soil physical properties were compared on three different treatments. Two treatments were different winter rye plots, one harvested in May and one in June, and the third was a control plot with no rye present. Samples were taken on four different occasions during the course of rye growth, September, November, May, and June.  These treatments were analyzed for physical properties, including a qualitative visual soil structure assessment (VSSA). The VSSA is done by removing a spadeful of soil from the ground, and observing its physical attributes. These attributes to a designed grid, assigning a visual quality score from one being the best, to five being the worst.  Cone penetration resistance, saturated hydraulic conductivity, dry aggregate distribution, and infiltration were also measured. The treatments that had the rye cover crops exhibited some improvement over the soils without the rye treatments, especially in visual score, dry aggregate distribution, and saturated hydraulic conductivity.  The soil quality improved under the rye system, but may not be sustainable in the long term.