What starts out as a small patch of tall, waving grass in the corner of a lot or in a ditch can soon become an acre or more of one of Wisconsin’s nastiest invasive species, Phragmites (frag•mi•tees). Once established it spreads rapidly and is difficult and costly to eradicate. It’s a problem because it grows in tightly packed bunches and reproduces through underground rhizomes choking out beneficial, native plants.
Unfortunately, it’s not the only invasive plant to overtake the Kewaunee County landscape. We’ve provided “mug shots” of the Dirty Seven. These invasives are considered harmful. If you see any of these plants in your area, don’t try to kill them yourself. Contact the Wisconsin Department of Natural Resources for backup. You can find more information about invasives at http://dnr.wi.gov/topic/Invasives/documents/wetland_species.pdf.
Be on the lookout for the Dirty Seven.
Phragmites or Giant Reed Grass: primary source from wetlands around Green Bay;
Common and Cut leaf Teasel: planted by dried flower hobbyists, early stages of establishment;
Japanese Knottweed: escaped from ornamental plantings;
Wild Parsnip: spreading in the area, plant sap can cause sever skin blisters, health hazard;
Giant Hogweed: outbreak in Manitowoc county, health hazard causing skin blisters;
Spotted Knapweed : found in sandy soils, emits its own chemical to suppress native plants;
Yellow Tansy: attractive ornamental plant, spreading in the lake shore area.