View as Webpage

Just waiting to take off. The two photos you see here are the overwintering basal rosettes of non-native, invasive spotted knapweed (Centaurea stoebe subsp. micranthos; above) and garlic mustard (Alliaria petiolata; at left). Their circular arrangements of leaves close to the ground enable the plant to absorb maximum sunlight and help crowd out competition.

In just a few months, these rosettes will give way to vertical shoots, flowers, and dreaded seeds.

But, you can nip them in the rosette—right now. Garlic mustard rosettes are easy to pull. Or, they can be treated with a 1 to 2% solution of glyphosate. A 0.5% solution of aminopyralid, such as Milestone®, is recommended to treat spotted knapweed (as well as teasel). While herbicides can take longer to kill invasives in winter rather than in the growing season, they can still be effective. And, because nearly all native plants are dormant now, there is little danger of damaging them with herbicide. If using herbicides, always follow label instructions.

Invasive plant control work never stops. All of us with MoIP encourage you to find and treat the basal rosettes of the three species mentioned above this winter—as well as the other species described below.

We hope you enjoy our news in this issue, summarized below, and, as always, please let us know your invasive plant-related questions, ideas, or concerns. We'd like to know what information you would find especially helpful for us to include in the Missouri Invasive Plant Council's (MoIP's) State of Invasives.

–Support Missouri Senate Bill 105 to Stop the Sale of Select Invasive Plants in Missouri: Public Hearing on Thursday, February 6, 8:30 a.m.

–2024 MoIP Invasive Plant Action Awardee

–Nominate an Invasive Plant Action Champion Today

–February 20: MoIP-organized MNRC workshop: Invasives Control Need-To Know: Four Quick Talks on New Herbicide Regulations & Formulas, Invasive Carp, and More

–Traits of Invasive Plants: MoIP Recorded Webinar

–Save the Date: April 22: MoIP Callery Pear Buyback in 17 Cities

–Missourians Making a Difference: Roxie Campbell

–Invasive Plant to Watch: Black jetbead

–Invasives to Treat in Winter: Japanese honeysuckle, tall fescue, wintercreeper, and (see above) basal rosettes of spotted knapweed, garlic mustard, and teasel.

Thank you for taking action to identify and control invasive plants!

Carol Davit, MoIP Chair

Photos above of spotted knapweed by Leslie J. Mehrhoff, University of Connecticut, Bugwood, and garlic mustard by Richard Gardner, Bugwood

Missouri Senate Bill 105, sponsored by Senator Bernskoetter, aims to halt the sale of five invasive plants in Missouri. The bill requires that all nurseries and nursery dealers in Missouri submit to the Missouri Department of Agriculture an affidavit that they will not intentionally import, export, buy, sell, transport, distribute or propagate any plants or seeds of climbing euonymus (Euonymus fortunei; also known as wintercreeper), Japanese honeysuckle (Lonicera japonica), or sericea lespedeza (Lespedeza cuneata) on or after January 1, 2027; or burning bush (Euonymus alatus) or Callery pear (Pyrus calleryana) on or after January 1, 2029. 

A public hearing for SB 105 will be held in the Missouri State Capitol on Thursday, February 6 at 8:30 a.m. in Senate Committee Room 1 on the first floor of the Missouri State Capitol. See this map of the first floor.

If you wish to testify in person, you will need to fill out this form. Copies of the form will be available in the hearing room, or, you can print and fill one out and and bring it with you to the hearing. (The Missouri Senate does not allow written testimony to be submitted at hearings.)

If you can not attend the hearing, MoIP encourages you to call or email members of the Senate Agriculture, Food Production, and Outdoor Resources Committee before the hearing and voice your support for SB 105. MoIP also encourages you to contact these committee members after the hearing as well, to reiterate your support and help address any questions they may have:

jason.Bean@senate.mo.gov, Committee Chair

jamie.Burger@senate.mo.gov, Committee Vice Chair

mike.bernskoetter@senate.mo.gov, SB 105 sponsor

sandy.crawford@senate.mo.gov

kurtis.gregory@senate.mo.gov

tracy.mccreery@senate.mo.gov

barbara.washington@senate.mo.gov

You may wish to consult the talking points about SB 105 here.

In the Missouri House, Representative Sassmann has introduced House Bill 60, which mirrors the Senate bill, but it has not yet been scheduled for a hearing.

Photo above, of invasive burning bush in a Barry County forest, by Carol Davit

Dr. Csengele Barta is the winner of the 2024 MoIP Invasive Plant Action Award, in the Researcher category, awarded to an individual who has published research on invasive plant management relevant to the ecology and agriculture of Missouri. Dr. Barta’s research has centered around the non-native, invasive Amur honeysuckle (Lonicera maackii) and the secondary metabolites it produces.

Secondary metabolites are substances manufactured by plants that make them competitive in their environment. Understanding the complex qualities of Amur honeysuckle’s secondary metabolites provides insight into its reproductive patterns and rates so researchers may uncover new effective methods of controlling this and other invasive plant species. 

In addition to her research, Dr. Barta is an admired instructor and mentor. She has been a professor of biology at Missouri Western State University in St. Joseph for the past 12 years, teaching plant molecular eco-physiology and biochemistry.

Congratulations, Dr. Barta, and thank you for your important work!

Photo above of Dr. Csengele Barta

Invasive plant detection, control, research, and planning is hard work. We are sure you know individuals and groups worthy of recognition for their efforts to take action to reduce the negative effects of invasive plants, and we encourage you to nominate them for an award.

MoIP established the Invasive Plant Action Award program to recognize the outstanding work being done in Missouri to control invasive plant species. The Action Awards celebrate exceptional effort and leadership in the field and also serve as a way to demonstrate to the broader community how controlling the spread of invasive plants on Missouri farms, forests, woodlands, prairies, gardens, parks, neighborhoods, roadsides, and along waterways is very possible and very important land stewardship. Members of MoIP evaluate nominations and select winners annually.

There are four MoIP award categories: Individual Citizen or Individual Organization; Individual Professional; Group Collaborators; and Researchers. Find details on each category, past winners, and the application form here. Nominations are due April 30, 2025.

Pictured above is 2021 MoIP Awardee Linda Lehrbaum, right, with MoIP Council member Malissa Briggler

The Missouri Natural Resources Conference (MNRC) is an annual meeting organized and sponsored by the Missouri Chapter of the American Fisheries Society, Missouri Chapter of the Society of American Foresters, Missouri Chapter of the Wildlife Society, and the Show-Me Chapter of the Soil and Water Conservation Society. The 2025 MNRC will be held at Lake of the Ozarks, February 19-21.

Among the MNRC learning opportunities is the following two-hour workshop organized by MoIP: Invasives Control Need-To-Know: Four Quick Talks on New Herbicide Regulations & Formulas, Invasive Carp, and More.

With invasive plants and animals as the second greatest threat to wildlife and habitats locally and globally, all natural resource professionals need up-to-date and practical information to carry out their work. Attendees of this workshop will learn about newly revised Application Exclusion Zone (AEZ) standards issued by the United States EPA, which will affect all herbicide applicators. Also to be presented will be information about the change in active ingredients in many general-use Roundup brand products, which have higher soil mobility and longer persistence, with potentially more severe environmental fates than glyphosate. Attendees will also learn about inspiring, innovative efforts to market invasive carp for human consumption in Missouri, the United States, and the world. Finally, the workshop will provide talking points for attendees to use when interacting with the general public about the problem with invasive plants and also the use of herbicide as a control method.

The MoIP-organized MNRC workshop has been tentatively scheduled for February 20, 1:00 p.m. MNRC registration information.

If you missed it when presented live on January 30, you can watch a recording of MoIP's webinar with Dr. Gabiella Nunez-Mir of the University of Illinois at Chicago on the Missouri Prairie Foundation's YouTube channel here.

The ability to forecast the invasive dynamics (e.g., establishment and impacts) of non-native plants is of critical importance to the prevention and mitigation of biological invasions. Species traits are a useful framework for characterizing invasiveness, as they are measurable proxies for mechanisms involved in resource acquisition, dispersal, and reproduction, indicating how an organism interacts with others and its surrounding environment.

However, despite an extensive body of research dedicated to this purpose, scientists still lack a reliable framework for traits-based invasion forecasting. In this webinar, learn about Dr. Gabriela Nunez-Mir's research to approach the study of mechanisms of invasion and their associated species traits macroecologically, which involves investigating the dynamics of hundreds of invasive plant species in different ecosystems across the continental United States.

MoIP, in partnership with Forest ReLeaf of Missouri, Forrest Keeling Nursery, and the Missouri Department of Conservation (MDC), will hold its annual Callery pear “buyback” event in 17 locations around Missouri on April 22, 2025.

Homeowners are invited to cut down one or more Callery (Bradford) pear trees (Pyrus calleryana) and register to receive one free, non-invasive tree at this event.

Registration will open March 17 and close on April 17. More information, a full list of host locations, and registration information is available here.

Photo collage above, by Tina Casagrand Foss, of MoIP Callery Pear Buyback participants' photos of their cut Callery pear trees.

Throughout Missouri, many individuals are making significant progress in the early detection and control of invasive plants. MoIP is pleased to highlight their efforts. 

Rock Bridge Memorial State Park Naturalist Roxie Campbell took time out of her busy schedule to describe her work. Enjoy! 

How long have you been at Rock Bridge, and what is your professional background?

I have enjoyed a 38.5-year career with Missouri State Parks. I’ve been the park naturalist at Rock Bridge Memorial State Park for the last 33 years. Missouri State Parks are by definition, places that are “the finest examples of Missouri’s natural (and cultural) landscapes.” It’s great to work at such a place and to have a mission to take care of this park’s resources and help people understand and experience them. 

After I earned a B.S. in forestry from the University of Missouri, I worked at a historic site, Prairie State Park, and then at Rock Bridge, focusing on its caves, so it would seem I landed far from forestry! However, Rock Bridge has forests and woodlands, and my degree gave me a good foundation for furthering my love of and care for nature. 

What are your responsibilities related to invasive plants?

In my early years at the park, I was just learning about invasive plants and began treating bush honeysuckle with the help of a few park volunteers, but as the problem of invasive plants increased, so did my time devoted to controlling them. 

In recent years, I have supervised the park’s stewardship crew—a small group of seasonal employees, mostly college students, who work primarily during the summer months to control invasive plants and carry out other natural resource stewardship. I have found it important when interviewing candidates to look for individuals who care about nature, are familiar with physical labor and things like ticks, and can describe differences in leaf shapes. 

How do you keep staff and seasonal employees motivated when working on invasive plants?

It’s important to help them understand the threat that invasive plants pose to our ecosystem and show them what’s at stake—the wonderful diversity of native plants and wildlife that we currently have. Read more here.

Photo of Roxie Campbell with a Callery pear tree (now gone!) in the Karst Trail area at Rock Bridge Memorial State Park by Lynne Hooper

In December 2024, biologists with the Missouri Department of Conservation documented a population of black jetbead (Rhodotypos scandens) at Daniel Boone Conservation Area in Warren County, Missouri.

Native to central China, Korea, and Japan, black jetbead was introduced into the United States in 1866 as an ornamental. This multi-stemmed deciduous shrub is in the rose family, matures to a height of 5 feet and width of 7 feet. The bright green leaves are opposite, simple and doubly serrate with a rough leaf surface 2 to 4 inches long and 1 to 2 inches wide.

Its growth habit is similar to that of bush honeysuckle, but its branches are more arching and open.

White flowers with four petals occur in small terminal clusters. The spring flowers give way to small black bead-like fruit in groups of four. It spreads by seed and by vegetative means.

This species can grow in full sun to full shade, but prefers full sun with moist, well-drained soils. It is adaptable to poor soils, various soil pH, soil compaction, shady spots, drought, shearing, heavy pruning, and urban tolerances such as pollution and salt tolerance.

Black jetbead has been documented in at least 17 states east of the Mississippi and Missouri.

To control it, small plants may be pulled, but it is important to remove the entire root system when doing so. Little information is available on herbicide treatment of this species, but applying a 2 to 4% solution of glyphosate with a 2.5% solution of liquid AMS (ammonium sulfate) to cut stems should be effective in winter. In the growing season, a foliar application of 2 to 4% glyphosate +2.5% liquid AMS should be effective.

Top photo by John Vogel; composite photo from MISIN.

Not all invasive plants are most effectively treated at the same time of year, and treatment methods can differ according to the seasons. Here, we highlight several woody species to treat in winter. You can find treatment guidelines for many invasive plants other than those highlighted below at moinvasives.org. 

Note: Treatment methods may differ considerably if invasives are found in otherwise intact, highly biologically diverse areas, in disturbed areas/altered landscapes, or if invasives are found in or near water. When using chemicals to treat invasives, always read label instructions.

Invasive vines can be especially tricky to treat, as they are often growing over desirable native vegetation. Two you can treat in winter with herbicide—without having to worry about harming native plants (as they are now dormant) are wintercreeper and Japanese honeysuckle. In winter, herbicide treatment will be most effective on warm days.

Wintercreeper (Euonymous fortunei) can be easily spotted in winter because its leaves are green or reddish. When the ground is wet, small vines can be pulled. Large stems climbing up trees can be carefully cut, with the cut stem treated with herbicide (40% triclopyr solution when above freezing). Foliage can be treated with a 3% triclopyr solution, mixed with a non-ionic surfactant along with methylated seed oil or similar crop oil to help the herbicide stay on the foliage for better uptake by the plant.

You can also flag larger areas for treatment in spring when new leaves emerge.

Japanese honeysuckle (Lonicera japonica) is a woody, perennial, evergreen to semi-evergreen vine that trails along the ground and can climb to more than 80 ft. in length.

Leaves are opposite, oval, and 1 to 2.5 in. long. Flowering occurs from April to July, when showy, fragrant, tubular, whitish-pink flowers develop in the axils of the leaves. The flowers turn cream-yellow as they age. The small, shiny globular fruits turn from green to black as they ripen. Each fruit contains 2 to 3 small brown to black seeds.

This pernicious vine can be treated during the dormant season by spraying the foliage with a 3% solution of glyphosate with surfactant and AMS (ammonium sulfate). Often, Japanese honeysuckle grows over native vegetation, so spraying it in the dormant season will not affect desirable plants. Prescribed burning, especially on low humidity days, can also set back Japanese honeysuckle, but may not kill it.

The non-native, invasive grass tall fescue (Festuca arundinaria) can be treated with glyphosate on warm days during the winter. The recommended control is through a foliar application of glyphosate with surfactant added. Often multiple applications are necessary to eradicate an established stand. One quart of glyphosate per acre in the winter is recommended. For spot treatment of isolated tall fescue plants, use 1% to 2% of glyphosate with surfactant.

Prescribed burning can also help control tall fescue, and in some cases, kill it, along with other invasive herbaceous plants like spotted knapweed and teasel rosettes, which are green in winter. 

Photos above of wintercreeper by Carol Davit; of Japanese honeysuckle by Chris Evans, and tall fescue by Carol Davit

State of Invasives aims to:

• Provide useful information to you/the leaders of your organization, agency, or business to help you recognize and control invasive plants and reduce their negative impacts, introduce you to our work, explain the challenges of invasive plants, and make the case for bold action and how this will benefit Missouri and Missourians. 

• Share talking points that you can use when communicating about invasive plant detection and control within your agency, business, or organization, and to your customers or stakeholders. 

• Empower you and your audiences to recognize invasive plants and take action—around your office building, behind your parking lot, on your back 40, right of way, back yard, around your crop field, or on any other land you or your group owns or manages. Our MoIP Video: A Landowner Tour is one of MoIP's many useful resources at moinvasives.org.

We hope the information in this enewsletter is helpful, and we’d like to hear from you. What questions or ideas do you have? Would you like to share the invasive plant action you or your organization or business are taking with us? If so, contact us at info@moinvasives.org.