The Potential of Grasses In Wisconsin Dairy Forage Systems
2022
- Marshfield Agricultural Research Station
Project Media
Alfalfa has been a foundational forage crop on Wisconsin dairy farms for decades, and for good reason. It has a reputation for its high quality forage and usefulness in a crop rotation. However, alfalfa has a tough time persisting in the poorly drained soils that characterize some of the state’s most dairy-dominant regions, leading to more tillage, expense and frustration for farmers already on tight profit margins. While alfalfa continues to be a great crop for many parts of the state, there are more appropriate options for areas with challenging soil conditions. Before alfalfa became popular, cool season grasses were the foundational forage crop. They are well-suited for Wisconsin, and while grasses are often perceived as being inferior to alfalfa in respect to forage quality due to higher fiber and lower crude protein, that is not necessarily always true. When managed appropriately, grasses have shown the potential to produce high quality forage, but this is not widely known across the industry as many nutritional standards and guidelines have been developed around alfalfa. Furthermore, the economic and environmental tradeoffs of managing grasses for high quality forage versus alfalfa are not well understood. Trials were conducted in 2020 and 2021 at the Marshfield Agricultural Research Station to explore the potential of various perennial and annual cool season grasses when managed for forage quality goals. Several species and varieties of perennial grasses were managed under an intense cutting (5x) schedule to evaluate yield and quality through the season. Italian ryegrass was managed under a similar cutting schedule and 7 different fertilization regimes (sources, rates, application methods) to evaluate yield and quality through the season. Perennial grasses seemed to show greater yield and quality potential than Italian ryegrass with less inputs of fertilizer-nitrogen (N) than Italian ryegrass required. Italian ryegrass yield and crude protein significantly increased as fertilizer-N was increased, but high rates of fertilizer exceed University recommendations, add significant cost of production, and leave a high amount of residual N in the soil as opposed to moderate fertilizer rates and other sources of fertilizer such as manure.