Haywood Extension, Waterways Association work to eradicate invasive plants
Invasive plants are a significant threat to forests, wildlife and water quality as they cause a decline in biodiversity by out-competing native plants for space, sunlight, water and nutrients.
This summer, Haywood Waterways Association led two volunteer groups on a mission targeting Japanese knotweed, a tall perennial, cane-like shrub. The groups were made up of several local citizens with a concern for water quality, as well as 30 volunteers from the Collierville United Methodist Church from Collierville, Tennessee, who came to the area as part of Lake Junaluska Assembly’s Youth in Missions program. The groups focused on the stream banks of Richland Creek at Vance Street Park to remove the knotweed, and other target species included multiflora rose, oriental bittersweet, Chinese privet and Japanese honeysuckle. When finished with the project, the volunteers had removed 27 large garbage bags full from a 150-foot section of stream bank.
“The Haywood County Cooperative Extension Office completed a fantastic stream restoration project at the park a few years ago," said Eric Romaniszyn, Haywood Waterways’ executive director. "Their project stopped erosion and improved habitat for aquatic animals. Many native species were planted to stabilize the stream banks. However, invasive species are moving in, and if they aren’t removed, can smother the natives and cause stream bank erosion again.”
Stream corridors are ideal for many invasive species. The open canopy allows sunlight to penetrate and support plants that out-compete native vegetation. Invasive species along streams pose a problem that can't be neglected — such species typically lack the deep, stabilizing root systems that help hold stream banks together and stop erosion.
“It is a constant fight trying to manage invasive species," said Bill Skelton, Haywood County Extension director. "Without the help of groups and volunteers like Haywood Waterways, it would be very difficult to maintain and protect the stabilization work already done.”
Invasive species cover and strangle native species and form an extremely dense understory that prevents any other species from growing. Vines like oriental bittersweet and Japanese honeysuckle can cause trees to fall and, when the canopy is open, it opens up new habitat for the invasive plants. Because wildlife is not adapted to exotic species, there is less food available for both terrestrial and aquatic animals.
Invasive plants also are a problem throughout the municipal landscape.
"Coupled with urban sprawl and mismanaged development, the biggest threat to our native plant species are invasive species," said Jonathan Yates, the Town of Waynesville’s horticulturalist. "Native plants that are vital to our various mountain ecosystems struggle to compete with the often more aggressive invasives.”
The Town of Waynesville uses several methods to remove invasive plants, including manual (by hand) and careful chemical treatments, which are effective if done correctly; however, chemical treatments cannot be used near water due to the impact on water quality. When removing invasive plants, persistence is key, Yates said.
“Don’t give up," he said. "It’s important to stay ahead of an invasive by removing them as quickly as they are spotted.”
Skelton added, “The name says it all — even after apparently removing them, they invade again. You must stay ahead of them.”
For more information on removing invasive plant species, contact the Cooperative Extension Office at 456-3575 or Haywood Waterways at 476-4667.