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We Value Your Input: Education Tools Survey

by MoIP

Complete the survey below (or click here to open in a new window) survey regarding educational tools to identify and control invasive plants. We have developed a statewide assessment of 142 invasive plants, a printable list of top 25 expanding invasive plants in Missouri, and a top 15 expanding invasive plants of the Glaciated Plains thus far and have plans for more in the future. Please answer the questions below to help MoIP help you.

Complete this survey by June 18th, 2021.

Help Stop Invasive Species: Missouri Invasive Plant Task Force presents Top 25 Expanding Invasive Plants list for public education during National Invasive Species Awareness Week Part I — February 22–28, 2021

by Tina Casagrand

Contact: Tina Casagrand, (417) 299-1794, [email protected]

FOR IMMEDIATE RELEASE

Help Stop Invasive Species: Missouri Invasive Plant Task Force presents Top 25 Expanding Invasive Plants list for public education during National Invasive Species Awareness Week Part I — February 22–28, 2021

Jefferson City, MO – The Missouri Invasive Plant Task Force (MoIP) released its 2021 list of Top Invasive Plants Expanding in Missouri.

“MoIP defines an ‘invasive plant’ as an aggressive, non-native species whose presence causes or is likely to cause economic or environmental harm,” says Carol Davit, chair of MoIP and executive director of the Missouri Prairie Foundation. “Not only do invasive plants impact private property, native biodiversity, and outdoor recreation such as hunting and hiking, but they also are costly to control.” Because of their vigorous expansion, the species on MoIP’s 2021 Top Invasive Plants Expanding in Missouri list are particularly important to identify and control. 

The list draws data from MoIP’s statewide assessment that was compiled and reviewed by experienced field biologists in Missouri. In addition to identifying invasive plant abundance and assessing the severity of the plants’ impact on natural communities, biologists estimated how rapidly the species’ ranges will expand to form new occurrences throughout each of Missouri’s primary ecological regions over the next 10 years. The list includes species such as Callery (Bradford) pear (Pyrus calleryana), garlic mustard (Alliaria petiolate), sericea lespedeza (Lespedeza cuneata), and invasive privets (Ligustrum spp.).

MoIP encourages land managers, property owners, outdoor recreationists, and conservation volunteers to educate themselves about how to identify and manage plants on the list. People may report observations of invasive plants in your area any time using the EDDMapS app. This real-time mapping system for documenting invasive species distribution is fast, easy to use and important for early detection and rapid response to invasive species before they become unmanageable problems.

National Invasive Species Awareness Weekfocuses attentionon the long-term ecological devastation and cost of invasive species and the urgent need for their early detection and control to minimize their negative impacts. Find many resources on the identification and control of invasive plants at moinvasives.org.

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The Missouri Invasive Plant Task Force (MoIP) is administered by Grow Native!—a 21-year-old native plant marketing and education program serving the lower Midwest. Grow Native! is the native plant marketing and education program of the nonprofit Missouri Prairie Foundation. For more information about MoIP, visit www.moinvasives.org, email [email protected] or call 417-299-1794; for more on the Grow Native! program at grownative.org or for more on the Missouri Prairie Foundation visit moprairie.org.

The North American Invasive Species Management Association’s mission is to support, promote, and empower invasive species prevention and management in North America. Since 1993, NAISMA has been growing programs that bridge jurisdictional and geographic divides. In addition to organizing a variety of professional development opportunities, housing the Certified Weed Free Products program, and operating the PlayCleanGo® program, NAISMA is the lead partner on NISAW. Learn more at naisma.org.

Good News for 2020: Individuals and Groups Recognized for Invasive Plant Action in Missouri

by Tina Casagrand

Contact: Tina Casagrand, 417-299-1794, [email protected]

FOR IMMEDIATE RELEASE

Good News for 2020: Individuals and Groups Recognized for Invasive Plant Action in Missouri

Awards program of the Missouri Invasive Plant Task Force recognizes exemplary work in invasive plant early detection and control. 

JEFFERSON CITY (November 12, 2019)—As public awareness grows about the harmful effects of invasive plants, the Missouri Invasive Plant Task Force (MoIP) recognized two individuals and one group in Missouri who have exhibited outstanding work controlling invasive plants on property across the state.

 

2020 Invasive Plant Action Award for Individual Citizen: Jason Bryan

MoIP members chose Boone County landowner Jason Bryan as the recipient of the Individual Citizen award. “Like most landowners I deal with, Jason was interested in managing his property for better wildlife habitat to increase deer and turkey use, but most importantly he wanted to leave the property in better shape that it currently was,” Missouri Department of Conservation (MDC) Private Land Conservationist Ryan Lueckenhoff wrote in his nomination. He noted that multiflora rose (Rosa multiflora), wintercreeper (Euonymus fortunei `Coloratus’) and bush honeysuckle (Lonicera maackii and Lonicera x bella) were common through the wooded areas on the property, and they were getting worse. On one rocky outcrop, Lueckenhoff says, “Bush honeysuckle was so thick that you could not see from the top of the hillside through to the bottom and little to no wildlife were using the area.” He worked with Bryan to develop a 10-year plan for the property, with invasive species removal at the top of the list. The Bryan family started removing invasive plants the first year and have seen incredible success, with new visibility and returned wildlife.

hillside after invasive honeysuckle treatment

Hillside in which honeysuckle was covering the rock faces, which are in the background. Sixty percent of honeysuckle had a 4-7’’ base. Bryan used a hack and squirt method to treat the invasive plants and anticipates needing to follow up with spraying new shoots in a year. Photo provided by Jason Bryan.

Members of MoIP have gathered resources, tools, and guides that help landowners understand, assess, and manage invasive and exotic plants  commonly found in Missouri, including those found on Bryan’s property. Lueckenhoff added that Bryan understands the importance of follow-up treatments. “His commitment to this removal effort has been awesome to see!”

 

2020 Invasive Plant Action Award for Individual Professional: Roger Frazier

MDC and MoDOT crews on right of way

Spearheading the development of the Southeast Missouri Region Invasive Species Strike Team is just one of Roger Frazier’s invasive plant accomplishments. Photo provided by Jan Dellamano.

MoIP is proud to present MDC Priority Habitat Coordinator Roger Frazier with the Individual Professional award. “Roger Frazier has a long history of supporting Conservation for all the right reasons,” writes MDC private land services chief Jason Jensen in his nomination. “For him, it is not just a job, and not even just a profession; it is his passion and his lifelong commitment to protect, conserve, and serve Missouri’s Natural Heritage. But putting all that aside, we are nominating him for this award because of his recent efforts that have gone way beyond even what the most demanding of us would call above and beyond.”

Among Frazier’s invasive plant success stories are: 

  • developing the Southeast Missouri Region Invasive Species Strike Team. Notable for acting early on preventing several invasive plants (primarily common teaselDipsacus fullonum; cutleaf teaselDipsacus laciniatus; and spotted knapweedCentaurea stoebe) from spreading throughout the Southeast region, thus protecting Conservation Opportunity Areas. Frazier worked closely and tirelessly with the Missouri Department of Transportation (MoDOT) to manage highway right of ways for preventing the species’ spread.
  • serving as a member of MDC’s Invasive Species Coordination Team since its inception.
  • helping to start and secure funding for the Scenic Rivers Invasive Species Partnership, and
  • working with the City of Farmington and AmeriCorps on the Engler Park Eradication project.

Furthermore, Frazier’s duties as Priority Habitat Coordinator have kept him continually engaged with both MDC and Natural Resources Conservation Service staff on invasive species management on private land. “For those of us that work alongside Roger, even these words do not fully express the level of commitment and contribution Roger has made towards true invasive species management in Missouri,” Jensen writes.

 

2020 Invasive Plant Action Award for Group Collaboration: Jason Jensen, Jan Dellamano, Roger Frazier, Chris Rutledge, Mark Auffenberg, and Tony Jaco

mule vehicle and spraying invasives on roadside

Two state agencies and a nonprofit organization are engaged in a long-term project to address the growing problem of invasive plant spread on highway rights-of-ways. Photo provided by Chris Rutledge.

This group collaboration started in 2007 as a grassroots effort led by Jan Dellamano and the local MoDOT shed. Over the years, it has transformed into a long-term commitment to address the growing problem of invasive plant spread on highway rights-of-ways (ROW). This effort has been effective in stopping the spread of extremely invasive plants such as spotted knapweed (Centaurea stoebe L. subsp. micranthos) and teasel (Dipsacus fullonum L. and D. laciniatus)

This project has had many facets including conceptualizing, planning, gaining and developing administrative and budgetary support, equipment, and implementation on the ground.  All of this occurred with the cooperation of two state agencies (MDC and MoDOT), and a nonprofit organization, the Missouri Prairie Foundation (MPF). (MPF is excluded from the award, due to the nature of MoIP’s being housed under MPF’s Grow Native! program). 

I drive I-55 between Cape Girardeau to St. Louis with regularity, and I can see a clear difference between areas impacted by this arrangement and those that have no such treatment,” writes Tony Jaco, Southeast Regional Administrator for MDC, in his nomination. “I have witnessed a decline of teasel, sericia lespedeza, autumn olive, and spotted knapweed. This impacts the area treated with herbicides specifically, but it has a larger reach as the mowing equipment used by MODOT will not have carry as much seed debris from invasives which leads to spread of the invasives. It also benefits the watersheds I-55 touches because seed stock will not be flowing down stream to infect new properties.”

This pilot program has caught on and is being considered and/ or replicated in other parts of the state. 

 

The Action Awards seek to demonstrate how controlling the spread of  invasive plants on Missouri farms, forests, woodlands, prairies, gardens, roadsides and along waterways is wise stewardship. A recommendation by a natural resource professional is required to be eligible. Members of MoIP evaluate nominations. “There are many individuals and groups carrying out impressive invasive plant control in every corner of the state,” says Carol Davit, chair of MoIP and executive director of the Missouri Prairie Foundation. “We want to recognize those doing exemplary work and present them with an aware at an event of the awardee’s choice to be honored in front of their peers.”

By definition, invasive plants are those not native to a region whose abundance and/or rapid spread  harm economic and environmental resources. For more information on the awards program, please visit https://moinvasives.org/moip-invasive-plant-action-awards/

 

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The Missouri Invasive Plant Task Force (MoIP) is a resource of Grow Native!—a 19-year-old native plant marketing and education program serving the lower Midwest. Grow Native! is administratively housed by the nonprofit Missouri Prairie Foundation. For more information about MoIP, visit www.moinvasives.org, email [email protected] or call 417-299-1794; for more on the Grow Native! program at grownative.org or for more on the Missouri Prairie Foundation visit moprairie.org.

Awards Presented for Invasive Plant Action in Missouri

by Tina Casagrand
Awards Presented for Invasive Plant Action in Missouri
Socially distanced members of the award-winning team pictured above are (front, kneeling, from let): Kara Tvedt, Missouri Department of Conservation (MDC), Nate Muenks MDC and MoIP, Tyler Goodwyn, Greene County. (Standing, from left) Glen Locke, U.S. Army Corps of Engineers; Roddy Rogers, City Utilities of Springfield; Mike Kromrey, Watershed Committee of the Ozarks; Brent Stock, James River Basin Partnership; Ashton Stamper, Missouri Dept. of Natural Resources.

New awards program of the Missouri Invasive Plant Task Force to recognize exemplary work in invasive plant early detection and control. 

As public awareness grows about the harmful effects of invasive plants, the Missouri Invasive Plant Task Force (MoIP) bestowed new awards this year to recognize outstanding work controlling invasive plant species on property in Missouri. 

MoIP Chair Carol Davit presented Columbia Public Schools K-12 Science Coordinator Mike Szydlowski with the Invasive Plant Action Award for an Individual during the district’s October 12 school board meeting. Past Vice-chair Nate Muenks presented the Southwest Missouri Hydrilla Working Group with the Invasive Plant Action Award for a Collaborative Group during the Fellows Lake Hydrilla Event on August 12.

Carol Davit and Mike Szydlowski stand for invasive plant award

MoIP Chair Carol Davit poses for a socially distanced photo with Mike Szydlowski, who won the first MoIP Action Award for Individuals.

Szydlowski coordinated science teachers and students in a district-wide effort to remove invasive bush honeysuckle (Lonicera maackii and Lonicera x bella). According to the Missouri Botanical Garden, “Woodlands invaded by bush honeysuckle have dramatically reduced diversity and abundance of native plants compared to uninvaded woodlands, and severe infestations develop into impenetrable thickets in which native plants are almost completely eliminated.” Szydlowski’s project is responsible for eradicating approximately 2 million plants. In 2019 the project’s student volunteers accumulated a little over 7,000 service hours. 

hydrilla working group stand for award

Socially distanced members of the award-winning team pictured above are (front, kneeling, from let): Kara Tvedt, Missouri Department of Conservation (MDC), Nate Muenks MDC and MoIP, Tyler Goodwyn, Greene County. (Standing, from left) Glen Locke, U.S. Army Corps of Engineers; Roddy Rogers, City Utilities of Springfield; Mike Kromrey, Watershed Committee of the Ozarks; Brent Stock, James River Basin Partnership; Ashton Stamper, Missouri Dept. of Natural Resources.

The Southwest Missouri Hydrilla Working Group is a collaborative effort among representatives from City Utilities of Springfield, the Missouri Department of Natural Resources—Southwest Regional Office, U.S. Army Corps of Engineers (Pomme de Terre and Stockton Lake), Greene County, Watershed Committee of the Ozarks, the James River Basin Partnership, and the Missouri Department of Conservation (MDC) to detect and manage Hydrilla. In the summer of 2012, the exotic invasive plant hydrilla was verified in several private impoundments along South Fork, a headwater tributary to the Pomme de Terre River in rural Greene County, Missouri.  Since then, it has been detected in impoundments in the upper Pomme de Terre River, Little Sac River, James River, and Niangua River watersheds. Currently, hydrilla has been found in 35 sites in southwest Missouri. 

Hydrilla’s dense vegetative mats can clog intake structures at water power generation and water supply facilities and can also have negative impacts on recreational boating. States with heavy hydrilla infestations are spending millions of dollars annually to control hydrilla, which is frequently referred to as “the worst aquatic weed in the country.” A significant highlight for the Hydrilla Eradication project in 2019 was the addition of several more sites to the “monitoring-only” phase. Nate Muenks, MDC’s natural resource management planner and past vice-chair of MoIP, presented the working group with its award in August.

A recommendation by a natural resource professional is required to be eligible. Members of MoIP evaluate nominations. MoIP is a resource of the Grow Native! program and the Missouri Prairie Foundation. 

“There are many individuals and groups carrying out impressive invasive species control in every corner of the state,” says Carol Davit, chair of MoIP and executive director of the Missouri Prairie Foundation. “We want to recognize those doing exemplary work and present them with an aware at an event of the awardee’s choice to be honored in front of their peers.”

By definition, invasive plants are those not native to a region whose abundance and/or rapid spread  harm economic and environmental resources. The Action Awards seek to demonstrate how controlling the spread of  invasive plants on Missouri farms, forests, woodlands, prairies, gardens, roadsides and along waterways is wise stewardship. 

For more information, please visit our Invasive Plant Action Awards page.

Missouri Department of Agriculture Asks Residents to Report Unsolicited Seed Shipments

by Tina Casagrand

JEFFERSON CITY, Mo. – The Missouri Department of Agriculture has received reports from residents of unsolicited seeds being delivered from foreign countries such as China and surrounding areas. Missouri’s announcement follows several states who have also reported packages of these seeds being delivered across the United States. Consistent with nationwide reports, the packages were labeled as jewelry, specifically stud earrings, bracelets and other accessories.

It is important to take steps to prevent the introduction of invasive species into Missouri to ensure safety of the environment, livestock and plants. The full risk associated with the seeds in question is unknown at this time. However, the seeds could be an invasive species that has the potential to destroy native plants and damage crops. Invasive species can also introduce diseases to plants and may be harmful to livestock.

If Missouri residents have received unsolicited seeds, the following guidance applies:

  1. Do not open the seed package.
  2. Do not plant the seeds if you have opened the package.
  3. Submit an online report to USDA verifying you have received unsolicited seeds.
  4. Do not dispose of the seeds, packages or envelopes until USDA provides further guidance.

The Missouri Department of Agriculture is playing a cooperative role in USDA’s investigation; however, USDA is leading the effort from the federal level. USDA’s Animal and Plant Health Inspection Service is also working closely with the Department of Homeland Security’s Customs and Border Protection to prevent the unlawful entry of prohibited seeds and protect U.S. agriculture from invasive pests and noxious weeds.

If opened, place seeds in a sealed bag and contact the Missouri Department of Agriculture’s Plant Industries Division by phone at (573) 751-2462 or by email at [email protected].

To learn more about the Missouri Department of Agriculture and its programs, visit Agriculture.Mo.Gov.

Invasive Landscaping Plants Now Illegal to Sell in Indiana

by Tina Casagrand

Among the big headlines this month was this big piece of invasive plant news from the Indianapolis Star: “Landscaping Plants Now Illegal to Sell in Indiana.”

“Under the Terrestrial Plant Rule, these plants are prohibited from being sold, gifted, exchanged or even transported within the state.”

The Missouri Invasive Plant Task Force has a vision and a strategy for how to achieve a similar result in Missouri. However, it takes time.

We welcome support for the effort as MoIP continues to pursue this goal. Please send us a message at info [at] moinvasives.org to see how your organization can be involved.

2020 Award Nominations

by Tina Casagrand

MPF President David Young presenting the 2019 MPF Dick Dawson Prairie Pioneer Award to Jon Wingo. Past awardees are listed at the MPF and Grow Native! links above.

MPF, its Grow Native! program, and the Missouri Invasive Plant Task Force (MoIP), which MPF administers, is now accepting nominations for its  MPF awards  (prairie pioneer, prairie professional, prairie communicator, prairie volunteer, and prairie landowner);  Grow Native! awards , and the MoIP Invasive Plant Action Award .

One need not be a member of MPF to be nominated for an award. Current MPF board members are not eligible to receive an award. If you nominated someone in the past who was not selected for an award, we encourage you to renominate that individual. Nominations for the  MPF awards  and  Grow Native! awards  must be received by June 15, 2020.
Nominations for the  MoIP award  must be received by August 1, 2020.
Depending on the current public health situation, the MPF and Grow Native! Native Plant Pioneer Awards will be announced and presented at MPF’s Annual Dinner in Jefferson City, MO on August 8, 2020. We plan to present the Grow Native! Ambassador Award at the Grow Native! Professional Member Conference in November 2020. The MoIP Award will be presented at a venue of the awardee’s choice.
We appreciate and value your interest in and support of MPF, our Grow Native! program, and the Missouri Invasive Plant Task Force.

You Should Be Concerned When This Plant Goes Vertical

by Tina Casagrand
You Should Be Concerned When This Plant Goes Vertical
Alan Cain, groundskeeper at STLCC Meramec, saws and treats the roots of a dense stand of Euonymus fortunei `Coloratus’ (wintercreeper euonymus). The plant had completely surrounded the trunk of a sycamore on campus.

St. Louis Community College-Meramec takes action to remove an aggressive, exotic vine that is invading St. Louis and Missouri.

The sycamore tree was so smothered by a dense vine that its white trunk appeared green. The campus of St. Louis Community College-Meramec (STLCC) had been invaded by Euonymus fortunei ‘Coloratus’ (commonly known as wintercreeper euonymus or Climbing Euonymus), and if the facilities department didn’t do something soon, the problem would get worse. They tasked groundskeeper Alan Cain to liberate the sycamore and 32 other trees.

“This will be an ongoing effort as we work to remove the Euonymus fortunei on the campus,” says Kelly Crandall, building and grounds supervisor for the campus. “Hopefully we will be able to remove individual plants as we recognize them once we have established control.”

How did this plant become such a problem? According to a fact sheet developed by the Missouri Department of Conservation, wintercreeper euonymus—a broadleaf semi-evergreen creeping vine—“was chosen for cultivation because it grows rapidly, even under harsh conditions. Found in a variety of habitats, wintercreeper euonymus can tolerate full sun, heavy shade and moist soil conditions.” 

It establishes easily in disturbed or neglected soil, so many places where humans have altered the landscape are prime ground for wintercreeper colonies. The vine’s aggressive growth robs native plants of their chance to grow, preventing them from being vital food and nectar sources for beneficial wildlife such as pollinating insects. 

Wintercreeper euonymus has been a mainstay non-native horticultural ground cover used for many years, to cover, as a turf alternative, landscape areas with poor soils, soil moisture limitations, and challenging exposure extremes, including extreme deep shade. As a horizontal ground cover, wintercreeper euonymus bears no fruit/seed, but its vertical vining form produces copious volumes of fruit that is favored by birds. Birds ultimately spread the seeds to landscape and garden areas where wintercreeper euonymus may not be intended nor desired and considered a weedy pest. Once established, wintercreeper euonymus can dominate the woodland floor, thus eliminating a diversity of wildflowers and other understory plants.


Grounds staff removed Euonymus fortunei vines from 32 tree trunks on campus. The vine’s aggressive growth robs native plants of their chance to grow, preventing them from being vital food and nectar sources for beneficial wildlife such as pollinating insects.

Beyond the ground level impact, the vertical vining growth of wintercreeper euonymus can impose structural damage, potentially inflicting death to trees and shrubs.

A statewide assessment organized by the Missouri Invasive Plant Task Force (MoIP) found wintercreeper euonymus expanding its range at a moderate increase around St. Louis and causing moderate to severe environmental degradation in all regions of the state where data were reported. The abundance of escaped populations is particularly high the ecoregion that includes St. Louis. More than two dozen field experts assessed 142 invasive species for this assessment. The data were released in early 2019.

An inter-agency and inter-organizational resource of the Missouri Prairie Foundation’s Grow Native! program, MoIP has the principal goal of making early detection and control of invasive plants a higher statewide priority. The MoIP website offers resources on how to control highly invasive species such as wintercreeper. “In addition to encouraging landowners to keep invasive species from spreading,” said Carol Davit, Executive Director of the Missouri Prairie Foundation, the nonprofit land trust that runs the Grow Native! Program and MoIP, “We also want to teach people how to plant beneficial native species in place of invasive plants.” 

Alternative native, ground covers include golden groundsel (Packera obovatus) wild strawberry (Fragaria virginiana), three-leaved stonecrop (Sedum ternatum), wild ginger (Asarum canadense), calamint (Clinopodium arkansanum) and pussytoes (Antennaria parlinii). This web page from the Missouri Botanical Garden offers photos of native plants for comparison, as well as links to instructions on how to manage invasive plants on your property. The Grow Native! Native Plant Database offers hundreds of native plants with customizable search options to choose other alternatives.

Wintercreeper euonymus can be identified by its dense groundcover up to three feet in height. Its thick, glossy leaves are oval-shaped, no more than 1 inch in length, and easily identifiable by silvery white veins. Smooth, pinkish fruits mature in the fall. 

“Since the vertical growth of this highly aggressive  ground cover produces the seed producing fruit responsible for unintended  landscape invasion, STLCC’s removal efforts are a valuable asset for both the campus grounds and the surrounding residential neighborhoods,” says Bill Ruppert, Kirkwood resident who spearheaded the establishment of MoIP. The grounds staff began cutting vertical vines June 2019. In most cases, the vines are cut, treated and left on the tree to fall off on their own accord thereby eliminating bark damage. The staff completed the initial cutting and removal in July and will return after the first freeze this winter to remove or recut and treat vine stumps. (For details on how to treat cut stumps with herbicide, visit moinvasives.org.)

“I think this action demonstrates that STLCC is a  responsible college that is concerned with the spread of invasive plants in the community,” says Jerry Pence, Program Coordinator/Assistant Professor in the horticulture department at STLCC-Meramec. 

The results of disconnecting the vines from their roots. Note the new green growth at the base of the tree, indicating the need for post-cut treatment to prevent new vertical growth.

MoIP’s website offers guidelines on how to manage invasive plants.. For information on landscape services, including professionals specializing in removal of invasive plants, and who sell native plants and seed, please visit grownative.org.

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About the Missouri Invasive Plant Task Force

The Missouri Invasive Plant Task Force (MoIP) is a resource of Grow Native!—a 19-year-old native plant marketing and education program serving the lower Midwest. Grow Native! is administratively housed by the nonprofit Missouri Prairie Foundation. For more information about MoIP, visit www.moinvasives.org, email [email protected] or call 417-299-1794; for more on the Grow Native! program at grownative.org or for more on the Missouri Prairie Foundation visit moprairie.org.

About St. Louis Community College

Established in 1962, St. Louis Community College is the largest community college district in Missouri and one of the largest in the United States. STLCC has four campuses: Florissant Valley, Forest Park, Meramec and Wildwood. The College annually serves more than 50,000 students through credit courses, continuing education, and workforce development programs. For more information about STLCC, visit stlcc.edu

Sudden Oak Death confirmed in Missouri

Consumers should properly dispose of infected rhododendrons and lilac plants

[link to release]

JEFFERSON CITY, Mo. – The Missouri Department of Agriculture, in coordination with USDA Animal and Plant Inspection Service, has detected ramorum blight on rhododendron plants shipped to some retail nurseries in Missouri. The disease is more commonly known as Sudden Oak Death when it infects oak trees. The rhododendrons were shipped to Wal-Mart and Rural King stores throughout Missouri, as well as the Springfield Home Depot, Stark Bros. Nursery Garden Center and Fort Leonard Wood PX.  

Consumers who purchased rhododendrons or lilac plants of the known infected varieties labeled Park Hill Plants from these stores between March and June of this year should dispose of the plants immediately. Consumers who are unsure of their plant’s variety should look for wilting or browning leaves, leaf spots and twig dieback. If consumers notice these symptoms, they should contact the Department’s Plant Pest Control team at (573) 751-5505 and begin the disposal process.    

Varieties that have been infected should be disposed of immediately to prevent further spread of the disease. Plants may be destroyed by burning, deep burial or by double-bagging the plant with its root ball in heavy duty trash bags for disposal into a sanitary landfill (where allowable). Consumers should not mulch, compost or dispose of the plant material in municipal yard waste. Garden tools used to dig up any affected plants should also be sanitized before they are used again.

Sudden Oak Death is a form of ramorum blight and is caused by a fungus-like pathogen known as Phytophthora ramorum. Since the 1990s, the plant disease has caused mortality in some types of oak trees in California and Oregon, but it has not established itself in the Midwest. The disease has a host list of more than 100 species of trees and shrubs, including rhododendrons.

Since early June, the Department has worked alongside USDA-APHIS to visit more than 113 retail locations to collect samples and place potential host plants under quarantine. USDA-APHIS has worked with Wal-Mart to organize a voluntary recall of the impacted plants, while other locations have isolated or destroyed affected plants. Any remaining plants confirmed with ramorum blight, and any host species comingled with the confirmed positive plants, will be destroyed.

Shipment of these rhododendrons has been successfully traced back to Park Hills Plants in Oklahoma and may have originated from nurseries in Washington State and Canada. Plant varieties identified during the investigation, which is still partially ongoing, were shipped to at least 18 states.      

Specific varieties of rhododendrons that have tested positive in destination states include:

  • Cat Cunningham Blush
  • Firestorm
  • Holden
  • Nova Zembla
  • Percy Wiseman
  • Roseum Elegans
  • Wojnars Purple.

Specific varieties of lilac that have tested positive in destination states include:

  • Common Purple
  • Persian Lime

To learn more about the Missouri Department of Agriculture or its programs, visit Agriculture.Mo.Gov.