1. A Direct Approach to Measure Cover Crop Nitrogen Uptake from Dairy Manure Via 15N Enrichment

Fall manure applications are a standard practice across Wisconsin, primarily due to manure storage constraints and unpredictable spring field conditions. Unfortunately, manure derived nitrogen (N) is at risk for runoff and leaching into groundwater without an appropriate mechanism for N retention. Fall-planted grass cover crops can serve as N scavengers, reducing losses of manure N to the environment, especially post-silage harvest, however potential tradeoffs between sufficient N uptake and spring... T. Judd, M. Ruark, Z. Freedman