Location: Environmentally Integrated Dairy Management Research
2024 Annual Report
Objectives
Objective 1: Develop management practices for annual forage species planted after spring-harvested cover crops to enhance plant and animal productivity.
Sub-objective 1A: Evaluate productivity and nutritive value of annual forage species under different soil and management conditions planted after a spring-harvested cover crop.
Sub-objective 1B: Evaluate animal productivity of dairy heifers and lactating dairy cows fed forages of optimal quality based on results from sub-objective 1A for the specific dairy cattle groups.
Sub-objective 1C: Develop, improve, calibrate, and validate computer models that assess plant and animal responses to crop nutrient management in dairy cropping systems.
Objective 2: Develop manure application strategies to improve in-season manure nutrient use by perennial forages.
Sub-objective 2A: Evaluate effects of in-season liquid dairy manure application timing and techniques on cool-season perennial grass productivity and nutritive value, carbon and nitrogen losses, and soil nutrient changes.
Sub-objective 2B: Develop and validate computer models to predict soil and environmental responses due to nutrient application strategies in dairy production systems.
Objective 3: Develop management practices for grazing cattle on managed pasture that enhance both animal and plant productivity.
Sub-objective 3A: Evaluate productivity and nutritive value of novel forage species that may be further utilized in grazing systems.
Sub-objective 3B: Determine the production potential from dairy heifers raised on pastures, evaluating both plant and animal productivity, as well as pasture species management impact on nutrient cycling.
Approach
Dairy producers are increasing the harvest of cover crop forages planted after corn silage; however, there are often questions about subsequent forage crop options and best practices. Use of annual forages other than corn for silage can help break insect cycles that occur with consecutive seasons of growing corn and allows for increased application of manure to growing crops. Several forage species have been used with varying success due to lack of best management practices for the Midwest region. Also, raising dairy heifers on pasture is a win-win strategy for improving animal productivity and reducing the environmental footprint of dairy production. Raising replacement heifers on pasture can reduce the economic costs associated with this sector of dairy production. However, there is a lack of science-based recommendations for incorporating grazing practices into dairy systems. Furthermore, software modeling tools to help predict how changes to nutrient management and cropping systems affect forage productivity and the environment are lacking. To address these topics, the proposed research will evaluate the forage productivity and nutritive value of annual and perennial forage species under different management conditions and develop strategies for ensuring replacement dairy heifers can meet production targets through grazing or incorporation of alternative forages into the ration. The approach consists of experimental field work and model development, all organized under three broad objectives:
Objective 1: Develop management practices for annual forage species planted after spring-harvested cover crops to enhance plant and animal productivity.
Objective 2: Develop manure application strategies to improve in-season manure nutrient use by perennial forages.
Objective 3: Develop management practices for grazing cattle on managed pasture that enhance both animal and plant productivity.
These objectives impact dairy and forage production systems in the upper Midwest and elsewhere. Products and outcomes consist of best management practices for nutrient application of forages and harvest management; grazing management recommendations and fundamental knowledge of dairy heifer performance on pasture; and improved tools for modeling livestock production systems. Stakeholders include dairy and grazing-based producers, the dairy industry, and other crop farmers.
Progress Report
This is the first report for this new project which just began in February 2024 and continues research from the previous project, 5090-21630-001-000D, “Improving Sustainability and Forage Production Systems for the Upper Midwest.” Please see the report for the previous project for additional information.
Objective 1, Sub-objective 1A: An experiment evaluating new sorghum-sudangrass hybrids is continuing with its second year of plots established in Summer 2024 at two locations. The study will evaluate the new hybrids using either single harvest or multiple harvests to determine which hybrids perform best under different management. In addition, a new experiment to evaluate pearl millet using different harvest strategies has been started with plots planted in Summer 2024 at three locations.
Objective 2, Sub-objectives 2.A and 2.B: A new experiment was established in Spring 2024 to evaluate the use of different manure application methods (surface, injection, or trailing shoe) on perennial grasses (orchardgrass or tall fescue). Plots were established in April 2024 with soils sampled, fertilizer treatments applied, and greenhouse gas emission sampling conducted weekly. Due to wet conditions, first harvest of forage has been delayed and likely will only allow for a total of three forage harvests in 2024 instead of the four harvests initially planned. The study will be conducted over three years on the same plots each year.
Objective 3, Sub-objective 3.A: This project builds upon previous studies with black oat conducted at Marshfield, Wisconsin. A new experiment was established during Spring 2024. This experiment includes 12 black oat varieties, which will be evaluated for forage accumulation, maturity rates, and nutritive value across several harvests during the growing season. This experiment will be conducted over two growing seasons, establishing new plots each year.
Objective 3, Sub-objective 3.B.1 and 3.B.2: The grazing experiment was established during the Fall 2022. The first year of collection concluded in 2023. This grazing experiment will be conducted over two consecutive years, and the 2024 growing season will be the second and final year for this trial. Data collection is currently underway. The samples from the first year are being analyzed and a graduate student will be presenting a poster for the first year of results at a scientific conference this fiscal year. We expect to finish the data collection for this experiment by the end of 2024.
Accomplishments