Grazing Planted Prairie in WI: Pollinator and Pasture Value

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Commodities

Practices

• Crop Production: pollinator habitat

Farmland covers roughly ⅓ of the entire state of WI, with permanent pasture making up about 7% of the total farmland acreage. We know agriculture is a strong driver of biodiversity loss on the landscape that contributes to the disappearance of our native invertebrate pollinators. However, agriculture can also be a dedicated solution to this crisis by providing quality, long term habitat for wildlife. The goal of this project is to assess the effectiveness of planted prairie in supporting both pollinator life and productive cattle forage. We expect that the results from this project will inform if pastures can play a leading role in pollinator conservation and an on-the-ground study for graziers to refer to as they consider where or how prairie fits into their farm and grazing system.

To assess the compatibility of diverse planted prairie as both pollinator habitat and cattle pasture, we will survey the nutritional quality, floral resources, and invertebrate pollinator presence in a planted prairie pasture under different grazing pressures. In addition, we will also track how cattle grazing may influence (short-term) the prairie pasture plant community and collect baseline data on soil health in the prairie pasture system.

A diverse prairie mix was planted in the spring of 2018 and managed through two seasons of establishment before being burned and rotationally grazed for the first time in 2021. The prairie pasture will be divided into multiple paddocks of 1 - 3 acres to allow for a comparison of different grazing intensities with paddocks grazed at 0, 1, and 2 grazings through the growing season. Cattle will be rotated through each paddock, grazing for one to two days to a vegetation height of about 8” and then allowed to rest a minimum of 40 days before any subsequent grazing (if any). Pre- and post-grazed vegetation height will be measured using a pasture stick to track growth and recovery. Soils will also be collected and analyzed to assess soil characteristics, including bioactivity, to better inform how prairie pastures may compare to other pasture or cropping systems.

From late-May to September 1st of 2023 and 2024, we will collect bi-weekly (every other week) vegetation samples for lab analysis of forage quality to track how nutrients change throughout the growing season. Previous to and post grazing, each prairie paddock will be rapidly surveyed for vegetation composition (richness and abundance). In addition, prairie paddocks will be surveyed at least three times through the 2023 and 2024 growing season for floral resources (richness and abundance of blooms) and pollinator presence (richness and abundance). Floral and pollinator surveys will be conducted before and after grazing “disturbances” to assess how floral bloom and pollinator presence may change with time since grazing. To the best of our non-lethal means, pollinators will be identified to genus level (for butterflies) and functional grouping (for native bees) using Xerces’ Upper Midwest Community Science Pollinator Monitoring Guide.

During the two growing seasons of 2023 and 2024, we will:

1. Evaluate forage quality of diverse planted prairie using laboratory diagnosis
2. Evaluate flower richness and abundance through the growing season (June 1 - Oct. 1) of grazed prairie paddocks
3. Survey plant recovery from grazing and changes in plant species composition; specifically looking at changes in cover of functional groupings of species: warm season grasses, cool season grasses, forbs.
4. Survey pollinator presence (bees and butterflies)
5. Record baseline information on soil health of prairie pasture
6. Share findings through a field day, conference presentation, and a published “fact-sheet”