Invasive Plants

Canada thistle (Cirsium arvense) is an invasive species prevalent along sites on Blue Mesa Reservoir and Pioneer Point.

NPS Photo

Invasive species are non-native (exotic) species that causes harm to the environment, economy, or human, animal, or plant health. Invasive plant species can disrupt native ecosystems, outcompete or displace native plants, and alter functions within an ecosystem.

How They Spread

Seeds and plant parts are brought into the parks by wildlife, wind, water, and humans. Rapidly growing invasive plants can come in from population outside park boundaries. Once inside park boundaries, these species are aggressive and can spread quickly in both undisturbed and disturbed areas. Invasive plants negatively impact park resources and visitor experiences by impacting viewsheds, changing landscapes, and reducing native plant communities and animal habitats.

Some invasive plants are more prolific along roadways, drainages, and the Gunnison River due to disturbed soils and artificially created seed beds. Park visitors can spread seeds from shoes, tires, clothing, pets, or non-local firewood use. Invasive species do not always appear as weeds; some invasive species are colorful and look very similar to native plants. A visitor may have difficulty identifying an invasive species versus a native one.

 

Yellow sweet cover (Melilotus officinalis) and white sweet clover (Melilotus albus) are both invasive species with small flowers.

NPS/D. Goodman

Common Invasive Species at Curecanti

These species are given the highest priority for treatment at both Black Canyon of the Gunnison National Park and adjacent Curecanti National Recreation Area. Some of these species are more prolific in one park versus the other. Cheatgrass, Canada thistle, Musk thistle, Common mullelin, and Russian thistle are the most prevalent.

• Black henbane (Hyoscyamus niger)
• Bull thistle (Cirsium vulgare)
• Canada thistle (Cirsium arvense)
• Cheatgrass (Bromus tectorum)
• Chicory (Chichorium intybus)
• Common burdock (Arctium minus)
• Common hounds-tongue (Cynoglossum officinale)
• Common mullein (Verbascum thapsus)
• Curly dock (Rumex crispus)
• Dame’s rocket (Hesperis matronalis)
• Diffuse knapweed (Centaurea diffusa)
• Field bindweed (Convolvulus arvensis)
• Hoary cress (Cardaria draba)
• Kochia (Bassia scoparia)
• Musk thistle (Carduus nutans)
• Oxeye daisy (Leucanthemum vulgare)
• Perennial pepperweed (Lepidium latifolium)
• Prickly lettuce (Lactuca serriola)
• Russian knapweed (Centaurea repens)
• Russian thistle (Salsola tragus)
• Salt cedar (Tamarix spp.)
• Scentless chamomile (Matricaria perforate)
• Siberian elm (Ulmus pumila)
• Spotted knapweed (Centaurea maculosa)
• Storksbill (Erodium cicutarium)
• Sweet clovers (Melilotus albus and Melilotus officinalis)
• Tree-of-heaven (Ailanthus altissima)
• Tumble mustard (Sisymbrium altissimum)
• Yellow salsify (Tragopogon dubius)
• Yellow toadflax (Linaria vulgaris)

 

Park staff and interns use treatment methods to control invasive species.

NPS Photo

Control and Management

Some species are more easily controlled and managed with localized treatment. Others are more widespread. Although it may be almost impossible to eradicate a widespread invasive species, education and information are key to preventing spread to other areas.

National Park Service (NPS) ecology staff mostly prioritize invasive species management according to federal and state noxious weed lists. They also consider impacts of invasive plant species on native plant communities. Controlling the spread of cheatgrass, an invasive annual grass not listed on either the federal or state lists, is also a high priority. This is to protect Gunnison sage-grouse habitat and reduce the risk of severe and more frequent wildfires in sagebrush ecosystems.

Control methods can be cultural (prevention, reseeding, planting, or irrigation), manual (cutting, pulling, mowing or weed whacking), biological, or chemical (herbicides). NPS staff are required to confirm any treatment methods are compliant with the National Environmental Policy Act (NEPA) and other applicable laws.

 

Stop the Spread

Visitors can help stop the spread of invasive species before, during, and after their visit to Curecanti.

• Bring gaiters to cover socks and pant bottoms and clean your shoes or boots before hiking or walking. Use boot brushing stations when available.
• Be aware of your surroundings. Avoid brushing against plants and remove lingering seeds that may have attached to clothing, hats, or packs.
• Do not move firewood or bring wood from outside the area. If you are staying in a campground that has a fire ring and no fire restrictions, use local firewood.
• Shake out your tent, camp chairs, sleeping bags, blankets, and other camp gear to remove any plant or seed materials.
• Check and brush off any seeds that may have attached to pets.
• Wash your vehicle (cars or bikes), especially after traveling on unpaved surfaces. Seeds, leaves, stems, and other plant material can attach to tires and undercarriage.