Once Popular Landscape Selection Found to be Invasive

Winged burning bush (Euonymus alatus) has been a popular landscape choice for many homeowners over the years, but Purdue experts warn that the plant has escaped landscapes, and it is causing harm to natural ecosystems.

Purdue Extension forestry experts Brian Beheler, Don Carlson, Lenny Farlee, and Ron Rathfon recently co-authored an Extension publication on winged burning bush as part of Purdue Department of Forestry and Natural Resources’ Invasive Plant Series.

Named for its brilliant and vibrant red fall colors, winged burning bush has offered homeowners a landscape stand-out in the fall. It is a medium-sized deciduous shrub native to China, Japan and Korea. Leaves and branches are arranged oppositely, and twigs may have corky ridges or “wings”. Leaves are generally about ¾ inch to 2 inches long. It can grow up to 20 feet tall.

“Indiana has three native euonymus species that could be confused with winged euonymus,” the Purdue authors said. “The most likely encountered is eastern burning bush or wahoo (Euonymus atropurpureus), which is a shrub or small tree.” Wahoo usually has larger leaves, longer leaf stems, and a more erect form than winged burning bush, with pink 4-lobed capsules having red-orange fruit inside. Other native relatives are running euonymus or running strawberry bush (Euonymus obovatus - a perennial groundcover) and strawberry bush or brook euonymus (Euonymous americanus – a small shrub).

Although it is not illegal to sell, gift, barter, exchange, distribute, transport, or introduce winged burning bush plants in the state of Indiana according to Indiana’s Terrestrial Plant Rule (312 IAC 18-3-25), it is escaping our landscapes and establishing in natural areas, such as woodlands, prairies and other uncultivated areas. The authors assert that it has likely escaped cultivation in most, if not all, Indiana counties.

They stated, “The ability of winged burning bush to spread via seeds dispersed by birds, survive and produce seed in shaded environments, and gradually increase density and distribution in forests presents a threat to the native diversity and productivity of natural habitats in Indiana.” They said that besides seed production, winged burning bush stands can increase in density by layering, where a branch comes in contact with the soil and roots. “Research has shown that high deer population levels promote the establishment and spread of some invasive plant species, including winged burning bush,” they said. “Deer preferentially browse on desirable native plants while avoiding winged burning bush, giving it an additional advantage over native plants.”

According to Indiana Native Plant Society, some alternatives to winged burning bush for homeowners to consider include blackhaw (Viburnum prunifolium), highbush blueberry (Vaccinium corymbosum), red chokeberry (Aronia arbutifolia), and winterberry (Ilex verticillata).

Find the referenced Purdue publication at www.edustore.purdue.edu. Access an informational brochure about Indiana’s terrestrial plant rule at https://www.in.gov/dnr/files/ep-terrestrial_plant_rule.pdf. Learn about other invasive plants and organisms at https://ag.purdue.edu/reportinvasive/.