Southeastern Wisconsin Invasive Species Consortium, Inc.


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Early Detection and Rapid Response

Battling invasion by five prohibited plant species

wild chervilNot a moment’s rest for SEWISC. This season we are again mapping and managing populations of five NR-40 listed plant species that have crept into our 8-county region:

Wild chervil (Anthriscus sylvestris) (left) is an herbaceous biennial that grows up to 3.25 feet with hollow stems that are covered in hairs.  Plants grow aggressively to out-compete native vegetation and are forming extensive stands in Ozaukee, Sheboygan and Washington Counties.

Lesser celandine (Ranunculus ficaria)lesser celandine (right) grows as an herbaceous groundcover with kidney to heart-shaped leaves and yellow buttercup flowers.  Plants appear soon after snow melt and rapidly spread into new areas. After flowering in March and April, plants die back by June providing a very narrow window in which to search, identify and control this invader which is spreading in Milwaukee, Racine, Kenosha and Walworth Counties.

Tall manna grass (Glyceria maxima)tall manna grass (left) is an exotic, perennial grass capable of invading swamps, ditches, and marshes as well as edges of lakes, ponds, rivers, and creeks. Tall manna grass often forms huge monotypic stands that crowd out all native vegetation, ultimately eliminating habitat for native wildlife species. Preventing further dispersal, especially along streams, is critical. It readily produces seeds, especially right after initial invasion of a new site and is reported in Kenosha, Milwaukee, Ozaukee, Racine, Washington and Waukesha Counties.

Giant hogweed (Heracleum mantegazzianum)giant hogweed (below) is an herbaceous biennial or monocarpic perennial that grows as a bushy rosette the first year, and then bolts during the second year to 8-20 feet tall. The hollow, ridged stems are covered in coarse white hairs and reddish-purple mottling. Leaves are compound, 1 to 5 foot wide, palmate, deeply lobed and pointed. Flowers are large flat-top umbels, up to 20 inches wide, with white, 5-petaled flowers that bloom from May-July. To-date giant hogweed has been contained in Sheboygan County.
Sap from giant hogweed plants can cause severe burns and blisters!

water celery

Water celery (Oenanthe javonica) (left) invades aquatic and riparian wetland habitats, choking streams and displacing native riparian vegetation in Milwaukee and Waukesha Counties. The plant is most easily detected and identified August-September.  It reproduces by seeds and runners (stolons), which may extend into waterways and break off, spreading fragments that can establish new patches downstream.

Back By Popular Demand

This class fills fast! Many residents in southeastern Wisconsin work to control invasive plants in the areas we care about.  Take this class to ensure that you are using the most appropriate, efficient, up-to-date, and least environmentally damaging methods in those efforts.

Invasive Plant ClassSeptember 29, 2018;  9:00 am to 5:00 pm
Workshop fee: $60.00


Discounted fee of $45 offered to current SEWISC members


Contact us for details: (262) 675-6844
Available for 0.8 CEU

This is a hands-on class. After an introduction to the general ecology of the five functional groups of invasive plants (shrubs, perennial forbs, clonal perennials, grasses, and annuals/biennials), we will discuss, demonstrate and practice all applicable control methods (chemical and non-chemical) for these five plant types.

Topics will also include: 1) Identification of our common and relatively new invaders, 2) Planning and strategy for an effective control program, 3) Use of hand tools and herbicide application methods, 4) Herbicide concentrations, mixing, and safety, 5) Restoration strategies for badly infested sites, and 6) Record keeping.  Several take-home handouts and reference materials will be provided.  Register today!

New SEWISC Sign Salutes Individual Efforts

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Even the smallest of efforts can make a big difference toward reducing the impact of invasive species.  Urban landowners as well as those who own and manage larger acreages can now encourage good stewardship and backyard conservation practices by posting these signs. Whether you have rural acreage, a suburban yard, or a city lot, you can help protect the environment by controlling invasive species and promoting that stewardship practice to others.

The high-quality 9x12 inch aluminum signs are available for only $16.99 each or two for $29.99 (price includes shipping and handling).

To order just download, complete and send a SEWISC Sign Order Form with your payment.  ***Supplies are limited!***

SEWISC Assistance Program

2018 Awardees announced

We are excited to announce that 11 excellent proposals were submitted for funding to the 2018 SEWISC Assistance Program, which was graciously sponsored by the We Energies Foundation.  Although a challenging task, the selection committee chose five extraordinary on-the-ground invasive species control projects which will be conducted in our region over the next few months. The projects are summarized below:

seven grantSEWISC awarded $1,556 to the Friends of Grant Park for an invasive species control project including the removal of garlic mustard, dames rocket, porcelain berry, Oriental bittersweet, Japanese knotweed, burdock and invasive shrubs within a two-acre plot known as the Will-O-Way area.  Funding will be used to purchase equipment and supplies required to complete the project.  The work will be conducted by park natural areas staff and TNC interns.

Geneva Lake Conservancy was awarded $1,500 for a rapid response project in Walworth County to control the spread of lesser celandine.  The project is two-fold with public outreach and information gathering as well as an on-the-ground effort to chemically control one of the area’s most significant infestations in Walworth county. Our funds will be used to pay for the contracted herbicide application and sedge plugs that will be planted in the treated areas.  Work will be conducted by GLC staff, the WDNR, and contractors.

A $1,000 award was given to the Martha Watts for ongoing invasive species control on a portion of a 105-acre parcel located Village of Grafton.  The project will focus on controlling invasive vegetation within a beech-maple upland forest which contains a relatively high quality forested area.  SEWISC funds will be use to hire a contractor to perform select invasive species removals within the focus area.

SEWISC awarded $700 to Charles Heide for invasive species control at Fiddlehead Gardens, a 68-acre privately owned former farm.  The funds will be used to purchase herbicide and permanent equipment for the site that can be used by the growing volunteer team. This project will focus on eliminating garlic mustard, honeysuckle, buckthorn and burdock.  Work will be conducted by volunteers and contracted professionals.

Last, but certainly not least, $238 was awarded to Weed Out! Racine for an invasive shrub control project at Colonial Park.  The project will focus on controlling buckthorn and honeysuckle re-sprouts that have been previously mowed by parks staff. The funds provided by SEWISC will be used to purchase a backpack sprayer.  The herbicide will be provided by the City of Racine Department of Parks, Recreation and Cultural Services and the treatments will be made by volunteers.

Funding for the 2018 SEWISC Assistance program was graciously provided by the We Energies Foundation. Watch for our 2019 call for applications in early January

Garlic Mustard Pull-A-Thon

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Garlic mustard is an invasive plant that’s taking over our woodlands. It crowds out our beautiful native wildflowers and endangers forests by preventing tree seedlings from growing. To make matters worse, none of our native insects or wildlife eat it!

2017 trophy team

Help us remove this invader and keep our local natural areas healthy. Join us as we pull and bag garlic mustard for the 2018 Garlic Mustard Pull-A-Thon, a regional competition organized by SEWISC. You’ll help revitalize natural areas and raise funds for ongoing control, education and outreach.

A trophy and bragging rights will be awarded to the Pull-A-Thon Team that pulls the most garlic mustard/dame’s rocket and pulls in the most donations by June 30.  Hurry!  There are 3 ways you can still get involved with this fantastic effort:

Form a Pull-A-Thon Team

Join a Pull-A-Thon Team

Donate to a Pull-A-Thon Team

Wisconsin’s 14th Annual Invasive Species Awareness Month

Protect the places where you play: Keep invasives out!

wi invasive species counsil 

The 2018 Annual Invasive Species Awareness Month of June will be filled with events, a video contest, the annual Invader Crusader Awards, and more. 

Do you have your events all planned and just need to promote?  Email the ISAM Coordinator to register your invasive species workday, workshop, or other fun stuff. 

Click here for information and ideas on what the citizens of Wisconsin can do to help further our battle against invasive species.

Southern Wisconsin Restoration Field Day

restoration dayRiveredge Nature Center’s sanctuary has served as an incredible learning laboratory for those interested in ecology and restoration. The Center continues that legacy on Wednesday, August 22 with a special gathering for property owners, ecological professionals, naturalists, and students of all ages. This full-day workshop will make ecological management accessible to everyone as participants explore everything from planting native species, using dogs as an invasive species management tool, rare species preservation, restoration products, and so much more through a series of field demonstrations, lecture-style presentations, hands-on learning experiences, and vendor booths led by experts in restoration ecology and land management. Visit Restoration Field Day to learn more and to register!