You Should Be Concerned When This Plant Goes Vertical
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.
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.
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