Non-Native Invasive Species

One of the goals of the GMNF (Goal 2 of theForest Land And Resource Management Plan) is to maintain and restore quality, amount, and distribution of habitats to produce viable and sustainable populations of native and desirable non-native plants and animals. An objective within this goal is to minimize the adverse effects of non-native invasive species on National Forest resources.

Giant Hogweed (Heracleum mantegazzianum), a non-native invasive plant (NNIP) on the Federal Noxious Weed List, is an herbaceous plant that is generally more than 10 feet tall when it blooms, with stems about two inches in diameter. This is one plant you absolutely should not touch! Contact with this plant’s sap can cause photodermatitis - severe burns, blistering, painful sores, and purplish or blackened scars if affected skin is exposed to the sun. This species, while known from Vermont, has not yet been found on the GMNF. Dense patches can crowd out slower growing plants, displacing native plants that need direct sunlight to grow. The decreased abundance of beneficial native plants can reduce the quality of a site as wildlife habitat. When native riparian plants are displaced, stream bank erosion can increase and streambeds can be covered with silt. Photo by Leslie J. Mehrhoff of the Invasive Plants Atlas of New England.

For more information on identifying and controlling giant hogweed, visit the New York Sea Grant website:
http://www.dec.ny.gov/docs/lands_forests_pdf/ghfactnyseagrant.pdf

WHAT IS A NON-NATIVE INVASIVE SPECIES?
A non-native invasive species (NNIS)is an organism that has been purposefully or accidentally introduced outside its original geographic range, and that is able to proliferate and aggressively alter its new environment, causing harm to the economy, environment, or human health (Executive Order 13112, February 3, 1999).
To view the entire Executive Order, go to:
http://www.invasivespeciesinfo.gov/laws/execorder.shtml

Non-native invasive species are sometimes called invasive exotic species. Plant NNIS are also sometimes called “noxious weeds,” which is a broader term that may include problematic native and/or agricultural species.

WHY ARE NON-NATIVE INVASIVE SPECIES A PROBLEM?
Non-native invasive species infestations affect our ability to protect and maintain biological and ecological diversity, including conservation of species, communities, and ecosystems. Not all non-native plants pose a problem. Many of the plant species found in Vermont are non-native, and most do not pose a problem; many are valued for agricultural or horticultural purposes. Only those species that spread aggressively and out-compete native species are considered a problem.

Pictured here are several non-native invasive plants known from the GMNF; all photos by Leslie J. Mehrhoff of the Invasive Plants Atlas of New England (IPANE).

HOW DID NON-NATIVE INVASIVE SPECIES GET HERE?
For centuries, people have moved plants from one place to another to use as food, shelter, medicine, or for horticultural purposes. Other species have been introduced accidentally in the ballast of ships, or as “hitchhikers” on products that have been shipped around the world.

WHAT ARE SOME OF THE PATHWAYS FOR DISPERSAL?
Non-native invasive species disperse to new sites via a variety of means, including wind, water, the fur, feathers, and digestive tracts of wild and domestic animals, and vegetative reproduction. Patterns of infestation indicate that dispersal also follows human travel corridors (seeds are easily transported on people’s vehicles, footwear, clothing, and gear) and other linear openings. These pathways can provide the combination of disturbed ground, increased light, and avenues for seed movement that can enable NNIS to become established in new areas.

Wildlife biologist Rob Hoelscher photographed his socks after a walk in an upland opening.

WHAT IS THE GREEN MOUNTAINS NATIONAL FOREST DOING TO ADDRESS THE ISSUE OF NNIS?
The Green Mountain National Forest recently revised its Land and Resource Management Plan, which guides all natural resource management activities, establishes management goals and objectives, guides allocation of lands to different management emphases, and provides standards and guidelines for Plan implementation on the Forest over the next 10 to 15 years. Forest-wide and Management Area Standards and Guidelines are now in place which would reduce the spread of NNIS. Local standards and guidelines reflect national direction.

Volunteer Japanese knotweed control within the White River Floodplain Forest Restoration project

Vermont Youth Conservation Corps cuts back Japanese knotweed at sites along the White River designated for floodplain forest restoration; photo by Mike Bald

• Established the Upper White River Cooperative Weed Management Area (for general information on Cooperative Weed Management Areas go to the following location: http://www.mipn.org/MIPN%20Cookbook%20Lo-res.pdf

• Surveys for NNIS at most trailheads, parking lots, and campgrounds, as well as within many proposed project sites

• Initiation of equipment cleaning for timber harvest and openings maintenance activities

• Completed an environmental assessment of a variety of treatment techniques proposed for controlling non-native invasive plants (December, 2010)

HOW CAN I GET INVOLVED?
*Activities on the ground this year for which people can volunteer:

Forest Service staff, local volunteers, and the Vermont Youth Conservation Corps team up to pull wild chervil (Anthriscus sylvestris) along FR 54. Photo by Gudrun Keszocze, SCA intern with the GMNF

Local land owners and other partners attend a workshop on identifying and surveying for NNIS; photo by Mary Russ of the White River Partnership

• Remove NNIS from your own backyard and replace them with native plants. Useful websites:

Columbine (Aquilegia canadensis) is one of the many native plants that can work well in a local landscape. Photograph by Gudrun Keszocze

*Interested persons can contact Forest Botanist/ NNIS Coordinator, MaryBeth Deller at (802) 767-4261 x 524 or mdeller@fs.fed.us

FOR HELP IDENTIFYING THESE SPECIES:
The following websites provide useful descriptions, photographs, and illustrations:

	Common bittersweet (Celastrus orbiculata) has the ability to girdle and overtop adjacent vegetation – often to the detriment of native species.
	Morrow honeysuckle (Lonicera morrowii) displaces native shrubs that provide food with higher nutritional quality for wildlife.
	Japanese knotweed (Polygonum cuspidatum), widespread along many rivers, can form massive monocultures, where its root structure is thought to contribute to soil erosion and decreased water quality.
	Common buckthorn (Rhamnus cathartica), in addition to being nasty to walk through, provides wildlife food of poor nutritional quality.
	Purple loosestrife (Lythrum salicaria) is capable of forming dense stands that alter the structure and function of wetlands, including altering habitat wetland-dependent wildlife.
	Common reed (Phragmites australis) can change the structure and function of marsh ecosystems, and can increase the potential for winter fires.