Cover Crop Species Selection Trial

Kaye, Bradley, Luthard, and Lisenbee are managing a cover crop species selection trial that helps farmers determine which cover crops and mixtures meet their needs. An important component of this trial is a cover crop variability experiment. This experiment is analyzing nitrogen fertilizer levels, greenhouse gas emissions, and a suite of ecosystem services potentially provided by cover crops including increases in soil microbial community and corn pest resistance. One field site, which is about 30 acres in Rock Springs, PA, has been a testbed for many best management practices that the project is advancing. This long term site will continue to be a testbed for new experiments. A major goal of the team is to establish a coherent suite of best management practices that are effective, innovative, new, and poised for adoption.

Luthard is doing work specifically on how cover crops affect nutrient cycling across soil texture, so the team can extrapolate what they learn from their local site to other soil sites with other soil textures around the Chesapeake Bay watershed. Most of that work has to do with how they can use cover crops in combination with manure to achieve high yielding corn. If the manure brings a lot of phosphorus that can be coupled with a lot of nitrogen from legume cover crops, then theoretically no synthetic fertilizers may be needed.

Lisenbee has parameterized the Soil Water Assessment Tool (SWAT) to the cover crop site at Rock Springs, PA. Next, she will develop scenarios in SWAT to understand how environmental changes or climate change could affect nutrient cycling in the field. She is also looking to parameterize other adaptive management field sites in SWAT to be compared to field measurements. Lisenbee will be using SWAT to model multiple field sites across the Chesapeake Bay watershed to create a network of adaptive management sites with a range of physical characteristics synthesized through modeling.