If you don't know it, don't grow it. Avoid buying or growing plants such as purple loosestrife, English ivy, ribbongrass, and butterfly bush that are known to be invasive.
Be especially careful when buying plants and seeds on the internet or by mail order. You may unknowingly contribute to the spread of an invasive species from one part of the country to another. Although some companies have voluntarily withdrawn known invasives from sale or labeled these species high risk, many have not.
You can get lists of known invaders from state and federal agencies as well as non-profit groups such as The Nature Conservancy, Native Plant Societies, and Oregon Department of Agriculture (see the links below).
Tips For Stopping the Spread of Invasive Plants
- If you see your local nursery selling invasive plants or seeds, let them know about your concerns. Most are interested in avoiding problem species and will listen.
- Avoid buying and planting mixtures of seeds, especially ones labeled "wildflowers." Many contain invasive species. Others are too poorly labeled to tell.
- Landscape and garden with plants native to your area. Although many non-native plants are not invasive and can be grown without risk, emphasizing natives (especially pollinator-friendly species) can provide other advantages such as food, cover, or nesting sites for butterflies and birds. Native plants also require less water, fertilizers and pesticides.
- Don't dump your aquatic plants or aquarium water into local waters. Many plants for water gardens and aquaria are highly invasive. Eurasian watermilfoil, a notorious aquatic weed that spreads rapidly and replaces natives, is one example of a plant that became established after being discarded from a personal aquarium.
- Be a good neighbor. Never dispose of unwanted plants or lawn or garden clippings in a nearby park or natural area. Invasive plants can spread from plant fragments, seeds, and berries.
- Share your knowledge about the harm that invasives cause with your family, friends, coworkers and neighbors.
- Join a local invasive plant eradication effort.
- Learn to recognize common invaders and keep an eye out for signs of new ones. Check trees, gardens, vacant lots, roadsides, yards, agricultural areas, wetlands, ponds, and lakes. If you think you've found a new infestation, report it to your local soil and water conservation district or to www.oregoninvasiveshotline.org. Early detection is crucial to stopping an invasive from becoming permanently established.
These tips are modified from the Union of Concerned Scientists web site at www.ucsusa.org.
Invasive Plant Information on the Web
Information from the National Arboretum
What every gardener needs to know (blog)
Invasive Plant Lists by State
Oregon Department of Agriculture Noxious Weed Profiles
Native Plant Society, Emerald Chapter
Weeds Gone Wild
Information about Invasive Plant Control Methods
Take a Naturescaping workshop. Call 503-222-7645 or visit www.naturescape.org.
Three River Land Conservancy – Backyard Habitat Certification
Gaylen Beatty 503-699-9825
Join or volunteer with a local watershed project.
Portland Parks & Recreation
West Willamette Restoration Partnership
Volunteer Coordinator, Amanda Wilson, 503-699-9825
Portland Audubon Society – contact Deanna Sawtelle
firstname.lastname@example.org or 503-292-6855 ext. 108.
Multnomah Weed Watcher Training