Hands-on campus research project nips invasives in the bud
Eradicating non-native invasive plants that proliferate in several campus locations, Biology professors Jennifer Rhode, Jonathan Horton and David Clarke and six students took clippers and weed wrenches to English ivy, oriental bittersweet, honeysuckle, tree of heaven and privet hedge last summer. Their goal: make way for native plants, such as black cohosh, ladyslipper and shooting star, to grow on campus, restoring habitat and providing study sites for science students. Whether their work pays off remains to be seen, as they monitor areas around Pisgah House and the Reuter Center throughout this fall.
“The oriental bittersweet is an invasive woody climbing vine, and it’s harmful because it can weigh down trees or it can choke them,” Rhode said. “Invasive exotics like this are the most significant factors in degrading natural areas on campus and limiting their usefulness as outdoor teaching and research labs.”
Kayla Bott ’10, Jennafer Hamlin ’10, Anna Sitko ’09, Alice Smithlund ’10, Andrew Wilson ’10 and Harry Schulz received a total of $9,150 in undergraduate research grants for stipends and equipment to determine the best method for removal of oriental bittersweet and other exotics. Facilities Management landscaping and grounds crews worked with the group to employ chemical control techniques. “We are exploring the most effective way to eradicate the species as well as the most economical means, so we can ensure the invasives are permanently removed and the native species can recover,” Rhode said. “Mechanical removal took more time, but whether that stopped the invasives and will allow the native species to regrow is yet to be determined.”
The crew also plans to conduct similar removal projects at the U.S. Forest Service Bent Creek Experimental Station and Baldwin Gap, the North Carolina Arboretum and the Biltmore Estate.
“We are exploring the most effective way to eradicate the species as well as the most economical means, so we can ensure the invasives are permanently removed and the native species can recover.”
The bittersweet wars
Oriental bittersweet, native to China, is a popular landscaping plant used in folk arts such as basket weaving and wreath making. But oriental bittersweet is a foe of gardeners and homeowners in the region. Its woody vine steals light and nutrients from native herbs and shrubs, and the tree falls it triggers can damage property. Since its introduction to the United States around 1860, oriental bittersweet has spread to at least 24 states. Moist slopes and coves, common in Western North Carolina, are particularly susceptible to invasion by oriental bittersweet because their climatic conditions resemble those in bittersweet’s native range.