Plants (Invasive)

The invasive plant pages of Conservation Digest contain detailed information about individual NR40 listed invasive plants of Wisconsin.

Individual Invasive Plant Resources

Trees & Shrubs


Common Name

Scientific Name

common buckthorn Rhamnus cathartica
Japanese barberry Berberis thunbergii
prickly ash Zanthoxylum americanum
tree of heaven Ailanthus altissima


Grasses and forbs (Broadleaf)

Common Name

Scientific Name

palmer amaranth Amaranthus palmeri


Weeds verses invasive plants

These two terms can be confusing because both refer to plants that grow in places they are not wanted. Weeds are usually thought of as unwanted plants in a horticultural or agricultural setting (think your yard or cornfield). The term invasive plants refers to unwanted plants in a natural area, such as a prairie, wetland, savannah or woodland.


Wisconsin regulates a number of invasive species by listing them in section NR40 of the state administrative code. There are two categories of invasive plants called out in NR40, restricted plants and prohibited plants. Those plants categorized as restricted may not be bought, sold or transported within the state. Restricted plants are usually already established in the state and may be widespread in certain regions. If a landowner has these plants are their property, they are not required to remove them. Prohibited species either have not yet been found in Wisconsin, or they have only been found in a very small number of locations. The purpose for categorizing invasive plants as prohibited is to attempt to prevent them from becoming established in the state. Prohibited species have the restrictions regarding purchase, sale and transport. Additionally, they are to be reported to the Wisconsin DNR when found and removed as quickly as possible. Enforcement is approached from a cooperative and awareness standpoint, rather than through citations or forced removal. Plant industry representatives (nursery and greenhouse growers) are actively involved in the NR40 list creation and revision to minimize market disruption. Invasive plants are further categorized by county. An invasive species may be listed as restricted in one or more counties while prohibited in others, to prevent further spread. The Wisconsin DNR 2010 Invasive Plant List describes invasive species contained in the original NR40 regulation. The 2015 Invasive Plants List includes species added to the original list. There is a third category of unwanted plant not spelled out in NR40; that is noxious weeds. This is a very short list that seriously degrade farmland. 

Common Name

Scientific Name

Canada thistle Cirsium arvense(L.) Scop.
field bindweed, creeping Jenny Convolvulusarvensis L.
leafy spurge Euphorbia esulaL.
purple loosestrife Lythrum L.1
multiflora rose Rosa multifloraThunb.

Weeds/Invasive Plants Resources

Cooperative Weed Management Resources – A web page maintained by the Midwest Invasive Plant Network. When you are ready to work together with other landowners and land managers in your area, this page is an excellent way to find out if there is a CWMA in your area. If not, it has all the tools you and your neighbors need to start a CWMA.

Cooperative Weed Management Areas (CWMAs) in the Northeast and Midwest – A map showing the areas covered by CWMAs, with a key listing the name of each.

Invasive Plant Atlas of the United States – Works great but only if you know the name (common or scientific) of the invasive plant. A collaboration between the National Park Service, the University of Georgia Center for Invasive Species and Ecosystem Health, the Invasive Plant Atlas of New England and the Lady Bird Johnson Wildflower Center.

Invasive Plant Mapping Handbook – provides instruction for collecting and entering data into the Early Detection & Distribution Mapping System (EDDMapS).