Kohmann is an assistant professor in the Department of Plant and Agroecosystem Sciences and an extension specialist in the Division of Extension at UW–Madison.
Adequate nutrient management of forage crops is crucial to provide livestock with nutrients and energy for production and reduce risks to the environment. The dairy industry of Wisconsin relies heavily on corn silage production, often rotated with alfalfa harvested for hay in 3- to 4-year rotations. Liquid or dry manure from dairies is applied in these systems provide nutrients for plant growth and dispose of stored manure. Managing manure application adequately has proved effective to improve water quality in Wisconsin. Soil cover has also been identified as a major determinant in reducing nutrient losses from agroecosystems, reducing potential pollution to the environment. More specifically, studies of alfalfa interseeded into corn silage indicate significant reductions in nutrient losses through runoff, while increasing economical profitability at the system level. Another advantage of this practice is improving alfalfa production compared to typical spring seeding. There are currently no manure application recommendations specifically tailored to this novel system. This project aims to evaluate establishment, productivity, and nutritive value of alfalfa interseeded with corn silage receiving manure application and provide better manure application recommendations for this system. This project will also measure soil respiration across treatments to better understand how manure application might affect greenhouse gas emissions from manure application.