Benefits of increasing grazing height on weed suppression in grass based grazing systems

View the project final report

• 2009 annual report

Commodities

• Animals: bovine, goats, sheep
• Animal Products: dairy

Practices

• Animal Production: grazing management, grazing - rotational, preventive practices
• Education and Training: focus group, on-farm/ranch research, participatory research
• Farm Business Management: whole farm planning
• Pest Management: cultural control, weed ecology
• Production Systems: organic agriculture, transitioning to organic

Few studies provide information on how to maximize the prevention of emergence of weed species in grazing systems in Wisconsin without the use of herbicides. This research will assess whether increasing grazing heights in the fall will suppress weed emergence the following year. It will also account for changes in forage yield in the year following the treatment. I currently have funding to determine the mechanisms responsible for suppression of weed emergence and estimating how different grazing treatments affect yield of forage species. However, forage quality can be more important than quantity, most notably in the dairy sector. I would like to compare our forage quantity data with a forage quality analysis using a near infrared reflectance spectrometry (NIRS). It is crucial that recommendations include possible changes in forage quality as this can have a significant effect on animal weight gain as well as milk production. In Addition, to ensure that the practices we recommend are in line with typical farm practices I would like to hold two focus groups including farmers, agency staff, and extension. The first meeting would take place prior to the second years implementation. In conjunction with the producers, agency staff and extension agents I will use the data from year one to restructure the treatments to further examine which treatments had the most suppressive effects while providing acceptable forage quantity and quality into year two. Another focus group meeting will take place after the final results have been collected. At this meeting we will focus on evaluating the study. I feel it is extremely critical that producers are involved in the dissemination of the results as it encourages farmer implementation. The results of this project will include, presentations at field days, pasture walks, and conferences. I will conduct surveys following presentations to evaluate how the information was received.

Expected short-term outcomes will develop an understanding of how producers can balance suppression of weed seedling emergence with potential reductions in forage yield and quality by altering grazing heights. These outcomes will be directed towards the members of the focus group.

Intermediate outcomes will include the extension of this information to grazing networks and sustainable agriculture organizations as well as publication in peer reviewed journals. This information will include a discussion of the mechanisms we determined to suppress weed seedling emergence and how it can be applied to a range of grazing production systems (e.g. beef production, sheep production, dairy).

Long-term outcomes include a better understanding of how to use cultural practices to not only prevent weed emergence, but balance this prevention with forage quantity and quality. This research also has the potential to be useful in other areas where weed seedling suppression is desired, such as restorations in natural areas, or weed management for programs such as Conservation Reserve Program (CRP).