Southeastern Wisconsin Invasive Species Consortium, Inc.


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Let’s Control Some Monocarps

You know, those plants that produce seed once and then die

The Teasels, Wild parsnip, Sweet clover, Queen Anne’s lace, the biennial thistles, etc. are called biennials. Individual plants don’t all flower and make seed in their second year of growth so they can actually be short-lived perennials; but all these species are strictly monocarpic, which means that they always die completely after they make their seed.  Most grow as rosettes (a circular cluster of leaves that radiate from a center close to the ground like a dandelion) for their first year of growth, or until they bolt (send up a tall stalk from the center which will produce their flowers and seed).  Once they bolt, they have used up their central growing point and will not be alive the following year.  What lives on the following year is the seed that they have made; seeds of these species can remain viable in the soil for several (at least 6) years after they are produced.

Monocarp2There is just one basic strategy to control monocarps: keep them from making seed.  If you prevent any seed from being produced, you will eventually eradicate the invasive.  For these biennials, there are many control options depending on the season, including chemical control at any stage before mature seeds are formed, hand cutting, and mowing.  Since spring to early summer is the ideal time for cutting the crown of the plant from the root, we will describe that simple method here.

Most of these biennials are tap-rooted (excluding Teasel) and it is relatively simple to kill the plant by cutting the root off 1” to 2” below ground (even Teasel) with a sharp spade.  The best time to cut the plants is any time from when you can find the rosettes in the spring, before they have bolted, to after they have bolted as soon as blooms show.  If the bolted plants become too mature, there is a risk that seeds on the cut off tops will mature, and you may have to remove the heads and dispose of them.

Use your sharpened spade, or get yourself a “Parsnip Predator”, a modified spade which can make the job even easier (made available through The Prairie Enthusiasts).  Wear gloves because you will want to pull the remaining rosette after you cut it from the root to make sure it is not still connected to some fine roots.  Thistles are prickly, and wild parsnip sap causes skin burns, hence the gloves.  Insert your sharp spade at an angle right next to the center of the crown of the rosette (see illustration above), and poke it into the ground to sever the root.  Pull the remaining rosette out of the ground.  The method is so simple and quick (especially using the modified spade).  This is nothing more complicated than using a larger-scale old-fashioned dandelion digger. 

Happy control work!  The satisfaction of the invasive removal will be its own reward.

Tall Manna Grass

Help us to identify and report, but avoid infested sites

Glyceria maxima (a.k.a. Tall manna grass or Reed sweet grass) is an exotic, perennial grass capable of invading wetlands such as 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.

G max Ocon Riv BW 2016aThe grass was first reported in Wisconsin in 1975 in Racine County, and is currently confirmed in only 9 southeastern counties, though several populations have been reported elsewhere in the state. Under NR40 regulations it is therefore restricted in the southeast region and prohibited in the rest of the state where few stands might allow elimination and/or prevention. Nationally, its distribution has been limited to two east coast states, Washington State, and Wisconsin, but reports suggest it is starting to spread.

This invasive grass can cause unusual problems and will be especially difficult to control since it can grow on shallow stream beds up to 4 feet deep, often from bank to bank. In several southeastern Wisconsin streams it now grows so thickly that it slows or even blocks water flows. Ensuing problems can include reduced fish populations and recreation, increased stagnant water (more mosquitoes) and raised water levels upstream capable of killing adjacent upland vegetation. Controlling such sites will be difficult since the primary control option is use of herbicides, but use in flowing water systems is almost impossible.

Thus, preventing further dispersal by its several mechanisms, especially along streams, is critical. It readily produces seeds, especially right after initial invasion of a new site. Then it fills suitable locations vegetatively through extensive rhizome development. Seeds are easily transported by water and humans, but both rhizome and stem fragments can also grow roots to become new stands, especially when they are carried downstream and catch on new stream banks or beds.  Learn more by downloading this G. maxima fact sheet.

The limited spread of Tall manna grass has enabled WDNR to obtain limited federal funding to prevent its further spread, and eliminate stands where possible. To do so, the Department needs the help of all resource users, such as hunters, fishers, bird watchers, and boaters - everyone who accesses typical sites. All should learn to identify and report stands, and even more importantly, avoid aiding its dispersal by staying out of infested sites to avoid unknowingly picking up and moving seeds or releasing plant fragments into waters.

Recognize Tall manna grass by its typical locations, very early green-up in spring, 7+ foot flowering stems with a very wide, stiff  panicle, extensive and monotypic growth habit, and other physical traits, including leaf blades 8-18 mm wide, and leaf sheaths with a sticky feel when sliding a finger back and forth on it.

If you suspect this species, contact WDNR staff. Email:  or ; 608-266-2554.

SEWISC Assistance Program

2016 Awardees announced

Eighteen excellent proposals were submitted for funding to the 2016 SEWISC Assistance Program, which was graciously sponsored by the We Energies Foundation.  Although a challenging task, the selection committee chose four extraordinary on-the-ground invasive species control projects which will be conducted in our region over the next few months.  Here is a summary of those projects:

Riveredge Nature Center was awarded $557 to assist with an ongoing woody invasive species removal and monitoring program, strengthening their continuing efforts of education and multi-generational outreach at the Riveredge Creek State Natural Area.  Their project will focus on known populations of nine NR40 Restricted woody invasive species across a 110-acre project area of mosaic of mesic forest, wetland, and riparian edge.  SEWISC Assistance Program funds will be used to purchase crucial items such as herbicide, back pack sprayers and other equipment needed to control woody invasive species.

CCLT$990 was awarded to the Caledonia Conservancy Land Trust to reduce the density of and competition from invasive species in favor of a native shrub understory such as dogwood and viburnum. This project will control populations of hairy willow herb and a growing infestation of purple loosestrife in areas that support numerous native sedge species as well as promote establishment of native understory shrubs such as dogwood, viburnum, cherry and elderberry within their King’s Corner parcel.  SEWISC funds will be used to purchase herbicide, a backpack sprayer, personal protective equipment, and to support Conservancy staff.

A $2,000 award was given to the River Revitalization Foundation to remove various terrestrial invasive plant species from Gordon Park and along the Beerline Trail within the Milwaukee River Greenway.  The main focus of this project is to treat common reed grass, garlic mustard, common buckthorn, honeysuckle spp. and Japanese knotweed within the 19-acre project area.  SEWISC support will provide supplies such as herbicide, dye and various equipment to treat and remove target species from the project area.  The Foundation will work collaboratively with many student volunteers including University of Wisconsin-Milwaukee and the NCCC AmeriCorps to complete this project. 

The Waukesha County Land Conservancy was awarded $2,000 for controlling target invasive species within the Tamarack Swamp and Weiland Preserve.  The goals of this project include 1) removing target invasive species, 2) creating a Partners in Stewardship Program, 3) educating landowners and the public on land stewardship and the importance of removing invasive plants to restore wildlife habitat and native plant communities, and 4) establish and strengthen partnerships with business, educational institutions, service organizations and youth groups that perform stewardship activities on Conservancy lands.  SEWISC Assistance Program funds will be used to purchase herbicide and supplies, fund labor to treat the target invasive species, and develop educational materials including a manual for “How to Conduct a Workday” prepared by students from UW-Milwaukee. This manual will be used to train volunteer and student leaders to lead and conduct workdays.

Thank you to We Energies Foundation for supporting these vital efforts!WeEnergiesFoundation CLRhorz

Garlic Mustard Pull-A-Thon

The 2016 competition is underway - support your favorite team today!

Hundreds of volunteers are actively protecting the woodlands of their neighborhoods by teaming up to pull and bag garlic mustard and dame’s rocket throughout southeastern Wisconsin.  Our goal is to collectively pull 5,000 pounds in 2016 and raise essential funds for the fight against invasive species.  This annual spring event is a competition, a fundraiser, and a way for people to join together and have a positive impact on their environment.KinnickinnicRivPkwy Alverno College Team Green 4 27 13

Click here to SUPPORT your favorite team today:

  • Caledonia Conservancy Land Trust
  • Eagle Nature Trail
  • Mequon Nature Preserve
  • Milwaukee County Zoo
  • Riveredge Nature Center
  • River Revitalization Foundation
  • Sheboygan County YMCA Camp Y-Koda
  • Ulao Creek Partnership
  • University of Wisconsin-Milwaukee Conservation Club
  • Weed Out! Racine

All proceeds will be will be used for invasive species adult and youth education, prevention and control in southeastern Wisconsin. All pledge contributions are tax-deductible.  Our Traveling Trophy and bragging rights will be awarded to the Team that collects the most pledges and pulls the most garlic mustard by June 30th.

New State Pollinator Protection Plan

PPPCoverIn Wisconsin, pollinator-dependent crops account for over $55 million in annual production.  In 2014, amid concerns about pollinator declines, honey bee health issues and the future of honey and crop production, the State of Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) initiated a project to develop a statewide pollinator protection plan.  DATCP partnered with researchers at the University of Wisconsin-Madison to gather scientific research and information from a diverse array of stakeholders to guide plan development.

Because many pollinator issues affect a diversity of species, the plan focuses on both managed bees and wild pollinators found in Wisconsin. The plan has a statewide scope and applies to many contexts, rural and urban, agricultural and non-agricultural.

Now that the Wisconsin Pollinator Protection Plan is complete, we need your feedback!  Please review the plan and complete this 5-minute survey

Wisconsin’s 12th Annual Invasive Species Awareness Month

Protect the places where you play: Keep invasives out!

The 2016 Annual Invasive Species Awareness Month of June will be filled with 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 citizens of Wisconsin can do to help further our battle against invasive species.

Upper Midwest Invasive Species Conference

Plan to attend this 4th biennial conference

UMISCLOGO 2016The 2016 Upper Midwest Invasive Species Conference (UMISC) will be held in scenic La Crosse, Wisconsin on October 17-19.  Attendees will exchange information and expertise on all invasive aquatic and terrestrial plant, animal, insect and pathogen species.

The goal of UMISC is to strengthen management of invasive species, especially prevention, control, and containment.  Expected audience includes: researchers, land managers, natural resource professionals, university personnel, landscape and nursery professionals, agriculture and forestry employees, environmental specialists, lake association members, land owners, government agencies, non-governmental organizations, and anyone interested in managing the spread of invasive species in the Upper Midwest.  Go to: UMISC 2016 for more information and to register.