Prairie plantings consisting of a mixture of native grasses and forbs are one of the most threatened natural communities in the midwest

The Department of the Interior Fish and Wildlife Service Region 3 awarded the University of Wisconsin-Madison $115,000 under the National Wildlife Refuge System Enhancements program (CFDA 15.654) from June 1, 2022 to June 1, 2025. The cooperative agreement will support evaluating the effectiveness of a new herbicide, florpyrauxifen, in controlling invasive wild parsnip and wild carrot in prairie plantings in Wisconsin, while limiting injury to desirable forb species. Specifically, the University will test the herbicide's ability to control the invasive plants and whether pre-treating areas with burning or mowing improves results. If successful, the project aims to develop best management practices for controlling wild parsnip and wild carrot that provide long-term control while protecting native forbs. This would allow effective management of the invasive species and preservation of ecosystem services provided by prairie lands.

Invasive plants like wild carrot and wild parsnip commonly invade and dominate established prairies in the ST. Croix WMD, reducing the benefits of native prairies. Methods that successfully control these species exist but are difficult to use in prairie systems without severely impacting native forb species. Herbicides are a control option, but they injure/remove native forb species, therefore they are rarely used. A new herbicide, florpyrauxifen, shows promise as an alternative option for control. IT is highly effective at controlling wild parsnip and wild carrot and many forbs have tolerance to this product. We propose to evaluate the effectiveness of this new herbicide in 1) controlling wild parsnip and wild carrot and 2) injury to desirable vegetation as a result of application. As areas are often burned or mowed prior to application an additional goal is to determine if integrating these methods improves results. If this project is successful, effective wild parsnip/wild carrot best management practices would be developed that would provide long-lasting control while limiting injury to desirable forb species. This would allow for effective management of these invasive species and prevent any impacts to the ecosystem services these prairies provide.