The Midwest Invasive Plant Network has published an online search tool to find information on invasive species control- Invasive Plant Control Database. From this website, go to Resources and then to Tools. The MIPN database works best if you already know the invasive plant species that you have. To help with identification, the Herbarium at the University of Wisconsin-Green Bay has a very nice image catalog of invasive species in Wisconsin, including the counties where they have been found and species descriptions. Another great resource that categorizes the invasive species by habitat is hosted by Wisconsin’s Department of Natural Resources.
Still unsure of the plant species, try University of Wisconsin’s weed identification tool or go to the PlantDOC website to find your local Extension agent and submit a digital image for identification. The Extension Specialist for Invasive Plants at UW-Madison is Mark Renz and his contact information is here.