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Alex Wu

Project Title: 
The Fate of Cover Crop Nitrogen Across Agricultural Practices
Program Year: 
Environmental Science
Ashley Keiser

This summer, I had the opportunity to research nitrogen cycles within cover crops across different agricultural methods for the termination of the cover crops. Cover crops are very important for sustainable agriculture to reduce soil erosion, suppress weed growth, and retain soil nitrogen. The nitrogen retained in the cover crop biomass becomes a nitrogen source for cash crops during the growing season after they are terminated. This study looked specifically at disk tillage, herbicides, and roller crimpers for termination methods. We also factored in different percentages of the recommended nitrogen fertilization amount for corn plants. For this research project, we grew our pea and rye cover crops in a greenhouse, labeled with 15-N nitrogen. These cover crops were then harvested, dried, and cut into many small pieces. Litter bags were created using a 2mm window mesh to hold these cut pieces of pea and rye. Root bags were also assembled, with 53 μm mesh. These bags were then deployed into the field with 5 bags per corn plot, and were then collected throughout the growing season. Bags and soil samples were brought back to the lab to be analyzed. These samples are still being processed, and there are more samples to be collected throughout this Fall.

Alex Wu poster