View as Webpage

Happy Earth Week, and welcome to the fifth issue of State of Invasives—the quarterly enewsletter of the Missouri Invasive Plant Council (MoIP). Thank you for subscribing.

Regarding invasive plants in Missouri, today, April 15, is significant for two reasons:

—If you haven't already, MoIP encourages you to contact individual members of the Missouri Senate Agriculture, Food Production, and Outdoor Resources Committee today because tomorrow, April 16, the committee will vote on Senate Bill 1281. Read the details below.

—Today is the deadline to register for MoIP's 2024 Callery Pear Buyback event, taking place in 15 cities on April 23. Read the details below.

On the subject of Callery pear trees (Pyrus calleryana and cultivars), MoIP was mentioned in this March 25 USA Today article on states taking action to reduce the threat of these highly invasive trees. We appreciate this publicity and are pleased to learn about the increasing number of states working to control Callery pear.

We hope you enjoy our news and resources in this issue, and, as always, please let us know your invasive plant-related questions, ideas, or concerns. Here is a summary of more items in this issue:

—Voice support for SB 1281 today

—MoIP Callery Pear Buyback Events in 15 Missouri cities on April 23, 2024

—Call for MoIP Invasive Plant Action Award nominees: Due June 15

—April 26: Invasive Plant Workshop & Field Day in Dent County

—Free EDDMapS Training: May 22, 2024

—Honeysuckle removal events April 22 in Kansas City and April 27 in St. Louis

—Invasive Plant Mock Trial educational resources from MEEA

—Missourians Making a Difference: Jerod Huebner

—Invasives to treat in spring/early summer: Japanese hop, birdsfoot trefoil, Japanese knotweed, and Japanese stiltgrass

Thank you for your interest in taking action to control invasive plants!

Carol Davit, MoIP Chair

Matt Arndt, MoIP Vice Chair

Photo above of Callery pear leaves by Chuck Bargeron, UGA, Bugwood

Tomorrow, April 16, the Missouri Senate Agriculture, Food Production, and Outdoor Resources Committee is scheduled to vote on Missouri Senate Bill 1281 to prohibit the sale of a number of invasive plants. Please consider voicing your support today for SB 1281 by individually contacting members of the Senate committee, linked above.

As of this morning, Missouri House Bill 2412 to prohibit the sale of five invasive plants has not yet been scheduled for a House vote. Voice your support for HB 2412 by contacting your State Representative. Find his/her contact information here.

At left is wintercreeper (Euonymus fortunei), one of the species included in both SB 1281 and HB 2412, the sale of which would be prohibited if legislation passes. Photo courtesy of Bugwood.

MoIP, in partnership with the Missouri Department of Conservation, Forest ReLeaf, and Forrest Keeling Nursery, is preparing for the upcoming annual MoIP Callery Pear Buyback event on April 23, 2024 with registration closing today, April 15. Through this program, homeowners are invited to cut down one or more Callery (Bradford) pear trees and receive one free, non-invasive tree.

Thanks to partners and volunteers around the state, the program has expanded this year to include 15 locations in Missouri!

To be eligible for a free tree, participants register and submit a photo of their cut-down Callery pear tree(s). One free native tree will be provided to each registered participant at the selected location on the day of the event.

Registered participants can pick up their tree on April 23 from 3:00 p.m. to 6:00 p.m. at one of these event sites: Columbia, St. Louis, Joplin, Springfield, Lebanon, Cape Girardeau, Farmington, Kennett, Hannibal, Rolla, West Plains, Kirksville, and St. Joseph.

Register here for non-Kansas City locations. For Kansas City-area dates and locations, please visit the Deep Roots website. Please note that registration for the St. Louis, Springfield, and West Plains sites is now closed.

For more information about the Pear Buyback program and the invasive Callery pear, visit the MoIP Callery Pear Buyback page.

The Scenic Rivers Invasive Species Partnership and MU Extension in Dent County are hosting this workshop at the Dent County Extension Office in Salem, Missouri, on Friday, April 26 from from 10:00 a.m. to 3:00 p.m. Free registration includes lunch. The workshop will cover classroom and field identification of common invasives that landowners may encounter on their properties. Workshop participants will also practice safe herbicide handling, mixing, and application. Register here.

Enjoy fresh air and gain the satisfaction that you are leaving the world a better place by removing invasive bush honeysuckle at these upcoming events. No prior experience is necessary.

• Monday, April 22, 1:00 to 3:00 p.m. Join Bridging The Gap's Kansas City WildLands team for an Invasive Species Workday at Ernie Miller Park and Nature Center. During this event, volunteers will work alongside restoration experts to remove invasive plants, helping native flora and fauna flourish again. Learn more and register here.

• Saturday, April 27 from 9:00 a.m. to noon. Crestwood Park in St. Louis County will be the site for this "Honeysuckle Hack." Learn more and register here.

Photo of honeysuckle removal event by the late Edgar W. Schmidt

In 2018, Dale Dufur, the artist who spearheads the Think About Tables initiative to raise awareness about the threat of bush honeysuckle invasion (and a 2023 MoIP Invasive Plant Action awardee), took things to the next level by taking this invasive plant to trial. The trial, held at the Old Courthouse in St. Louis, was so fun, so engaging, and so chock-full of interdisciplinary learning that Dale and friends decided to develop a lesson plan so others could replicate the experience. And so began the work to develop a guide for teachers and students to stage their own mock trials of invasive plants.

Today, the Missouri Environmental Education Association provides the Invasive Plant Mock Trial education resource, which combines lessons on ecology and civic engagement. This immersive educational unit, recommended for grades 6 through 12, is available for free and challenges students to research invasive species and think about how humans regulate or change the environment through a mock trial. Learn more and download the resources here.

Information from MEEA. Photo above of bush honeysuckle invasion by Bill Ruppert

Wouldn't it be great if there was a way to map the presence of invasive plants throughout the country? Fortunately, there is! EDDMapS is a web-based mapping system for documenting invasive species and pest distribution. It is fast, easy to use, and doesn't require Geographic Information Systems (GIS) experience.

Launched in 2005 by the Center for Invasive Species and Ecosystem Health at the University of Georgia, the program has expanded to include the entire U.S. and Canada. Professionals and citizen scientists can help control invasive plants by documenting observations of invasive plants in Missouri to EDDMapS.

Rebekah Wallace, EDDMapS Coordinator & Bugwood Images Coordinator at the University of Georgia, will offer a free training via Zoom on May 22, 2024 at 4:00 p.m. This training session is open to all and will be part of the Missouri Prairie Foundation's webinar series.

Wednesday, May 22, 2024 at 4:00 p.m.

Free. Register here. A link to a recording of the training will be sent to all registrants.

P.S.: Save the date for a free webinar on herbicide use around aquatic areas with Lucas Madison on November 6, 2024. Watch for details in upcoming State of Invasives issues.

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

Jerod Huebner took time out of his busy schedule to describe his work. Enjoy!

How long have you been with the Missouri Prairie Foundation (MPF) and what are your primary responsibilities?

I have been with MPF for eight and a half years. I am in charge of stewardship for all of MPF's 35 properties, which total 4,900 acres across Missouri. This includes applying for and administering grants, writing contracts for several contractors that carry out a significant amount of work on our properties, and coordinating with our dedicated volunteers, whose participation in prescribed burns and other stewardship activities is invaluable.

I perform numerous stewardship activities myself, including invasive species control, prescribed burning, seed collection, establishment of prairie plantings, woodland thinning, plant and animal monitoring, and area and equipment maintenance as well as outreach and education activities. In addition, I carry out stewardship duties on multiple partner properties totaling nearly 500 acres.

What is your professional background?

I started working with the Missouri Department of Conservation (MDC) in 2005, while enrolled at the University of Missouri-Columbia. I received a Bachelor of Science degree in Fisheries and Wildlife. I worked in the MDC Central region for approximately eight years and the MPF St. Louis region as a wildlife biologist for MDC for two years before joining MPF.

What are some of the invasive plant control projects you have led over the years? Why are they important?

I currently lead all invasive species efforts on MPF sites. A number of MPF prairies are extremely rich in native plant species, with very few invasive plants, in part because of the current and past work that I and other MPF staff have done to look for and treat invasive plants when found—not once, but several times each growing season. This can be tedious work, but it is much better to be vigilant and have fewer invasives to treat than to let them spread and seriously degrade a prairie.

Seeing the diversity and abundance of native plants on our properties, including several that can survive nowhere else but on unplowed prairie, as well as the insects and other animals that depend on them, makes the invasive control work worthwhile.

I led similar efforts while working for the MDC St. Louis region, focusing primarily on bush honeysuckle. Working with regional staff, we eradicated hundreds of acres of honeysuckle via aerial spraying, foliar spraying, prescribed burning, and follow-up chemical treatment.

Additionally, we removed 15 acres of dense native (but aggressive) eastern red cedar on Labarque Creek Conservation Area from a sandstone glade. We cut and piled cedar slash for burning to minimize fire scarring on the glade. After many days of intense labor, the glade was fully cleared of cedar and closer to its historical conditions, which was satisfying. 

Read more

—Carol Davit, MoIP Chair

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 species to treat in spring and early summer. 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. In addition to the resources below, you may also find this table of invasive plant treatment methods for grasslands, from the Missouri Prairie Foundation, helpful.

Photos below by MDC; Flickr user John Munt; Tom Huette, USDA Forest Service, Bugwood.org; Chris Evans, Bugwood

Japanese hop (Humulus japonicus) is an herbaceous annual vine. Native to eastern Asia, it was imported to the United States in the late 1800s for use in Asian medicine and as an ornamental vine. Within Missouri, Japanese hop is found most commonly in the Missouri and Mississippi river corridors, but it is increasing its range within certain floodplains. Japanese hop outcompetes established vegetation in sunny areas with exposed moist soil.

This sprawling, twining, climbing vine has opposite, palmately divided leaves that are rough to the touch. It has inconspicuous green flowers, with male and female flowers on separate plants. Female flowers are borne on a drooping cone-like structure with overlapping scales (called hops). The stems have short, sharp, downward-pointing prickles.

In areas with light infestation, manual removal can work well within moist soil in early spring when the root system is small. (You will need sturdy gloves to protect your skin from the prickles!) The entire root and plant must be removed and taken off-site to prevent regrowth. Repeated pulling should continue until dieback in fall when new plants cease to emerge.

In areas with heavier infestations, a pre-emergent herbicide containing sulfometuron methyl (Oust® XP) applied in mid-March generally causes minimal or no damage to other perennial vegetation, eliminating the need to rescue desirable vegetation from an established hop infestation. Application of a pre-emergent herbicide followed by a foliar application of glyphosate or metsulfuron applied prior to seed production (mid-April to August) may provide the most effective control. Subsequent applications will be necessary to control germinating plants throughout the season to prevent seed production.

See this MDC Japanese hop page for more information.

In Missouri, birdsfoot trefoil (Lotus corniculatus) occurs statewide, but mostly north of the Missouri River in fields, roadsides, waste places, and on other disturbed areas.

Native to Europe, this plant was planted widely in Missouri to prevent erosion at highway construction sites. It is also planted for cattle forage, but when it escapes to native habitats, it causes ecological degradation.

Bird’s-foot trefoil is a many-branched perennial with prostrate to ascending stems reaching six to 24 inches tall. Flowers are in umbels, terminal, with the typical configuration of pea flowers, bright golden yellow. Blooms May–September. The leaves are compound, with 3 leaflets (a terminal and 2 opposite) some distance below. Two basal leaves are actually stipules, not technically part of the compound leaf, but added to the true leaflets it looks like there are 5 total leaflets. All are variably oblong. Fruits are beaked, slender, upright pods bearing 5-14 seeds.

To control it, low mowing can prevent flowers from going to seed. Chemical application is most effective in the spring or fall. MCPA and Clopyralid may be effective with repeated applications. Selective, postemergence herbicide combinations for effective control are:

2,4-D + MCPP + Dicamba -or-

MCPP + MCPA + Dicamba + Carfentrazone or Triclopyr

Find more details at the MDC birdsfoot trefoil page.

Japanese knotweed (Fallopia japonica) is an herbaceous perennial plant from Asia. In 1825 it was introduced from Japan to the United Kingdom as an ornamental plant. Knotweed was then brought to North America in the late 1800s for use in landscaping and erosion control. One of the worst invasive species in the world, Japanese knotweed can thrive in many places, harm native habitats, and even damage the foundations of buildings.

Japanese knotweed is typically found in wet soils in lowlands, wetlands, and along streams. It tolerates a wide range of growing conditions, including full sun, high salinity, and dry soil. Now scattered throughout Missouri, Japanese knotweed grows along rivers, streams, roadsides, utility rights-of-way, and crop fields.

It has large, heart-shaped leaves, pointed at the tip (3 to 6 inches), and grows 3 to 12 feet tall with a shrublike appearance. Sheathlike coverings and swollen nodes are found where the leaf meets the stem. It has white-to-greenish flower clusters in midsummer and small, winged seeds by August and September.

A foliar herbicide solution may be applied before seed formation in early summer and in the fall, often as a re-treatment. Effective herbicides include triclopyr, glyphosate, imazapyr, and picloram, used separately or in combination. Because knotweed thrives in streamside areas, choose herbicide based on location of plants and presence of non-target vegetation. Do not use triclopyr and picloram in wetlands or adjacent to water. If the foliar spray is not practical, try cutting along with use of herbicides. Cutting will remove the above-ground plant and stimulate the rhizomes below ground, so follow-up with herbicides is necessary.

See this MDC Japanese knotweed page for more details.

Japanese stiltgrass (Microstegium vimineum) is an annual grass native to eastern and central Asia. First discovered in Tennessee in 1919, stiltgrass may have accidentally escaped as a result of its use as packing material for Chinese porcelain. This invasive grass grows in moist, disturbed areas including stream banks, river bluffs, floodplains, forest wetlands, moist woodlands, old fields, uplands, thickets, roadside ditches, and utility rights-of-way.

Growing to about 3.5 feet tall, it has alternate, thin, pale-green, lance-shaped, 3-inch long leaves. It has a distinct silvery stripe of reflective hairs running down the center of the upper leaf surface. Flower spikes form at the slender stem tips in late August through early October.

Japanese stiltgrass occurs in a wide variety of habitats, tolerates shade, and seems to prefer acidic to neutral soils that are high in nitrogen.

Hand-pulling Japanese stiltgrass can damage native plants and disturb the soil, which provides opportunities for other invasive plants. To cause less damage to native broadleaf plants, use grass-selective herbicides with active ingredients fluazifop-p-butyl (such as Fusilade) or sethoxydim (such as Poast) in July and August before seed is produced. Annual herbicide applications will be necessary to control plants that germinate from seed that remains in the soil from past years. If treating the plants near water, use water-safe glyphosate.

See this MDC Japanese Stiltgrass page for more details.

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 many of MoIP's useful resources.

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.