Invasive plants can create all kinds of problems. They can easily spread by wind and water. People also can make the problem worse, either by accidentally carrying seeds in their shoes and clothes or by planting plants that they didn’t know were invasive. Even attempts to remove invasive plants can help move them somewhere else if we don’t dispose of the plants carefully and correctly.
Protect Oregon’s forests and natural areas
It is easy to accidentally carry seeds or pieces of invasive plants between your yard and wherever you hike, bike, or explore in our region. Seeds stick to your shoes, clothes, and boot laces. They catch on your dog’s fur and get stuck in the mud on your bike or car tires. You can stop these seeds from spreading.
Take a few minutes to clean up whenever you leave home or when you’re done with your hike or ride —
- Get the mud out of your tires and boots.
- Pull seeds from boot laces.
- Brush seeds out of your dog’s fur.
These may be hard habits to start, but they can make a big difference in stopping the spread of invasive plants.
Know what you’ve got before you plant it
Many of the plants we now see as invasive started in or spread from yards of well-meaning gardeners. Know what you’re planting.
- Avoid seed mixes, especially ones labeled "wildflowers." Many contain the seeds of invasive plants. Others are too poorly labeled to be sure about what’s in them.
- Don’t buy plants, seeds, tubers, bulbs, etc. online — even from well-known websites. Some invasive plants have recently become problems in the U.S. because people bought them online.
- Be careful when sharing or swapping plants and do your own research about what a plant actually is. If you’re not 100% certain what the plant is, don’t plant it in your yard or garden.
Use caution when removing invasive plants
When removing even a tiny infestation, follow these steps to make sure those removed plants don’t get started somewhere else.
- Never place plants or seeds in your compost or yard debris.
- Never throw pulled plants on the ground or into the street or sidewalk.
- Put all pulled plants, bulbs, or seeds in the trash.
- Wash all garden tools and gloves.
Be a good neighbor
Help protect the land around you, especially if you live next to a park, forest, stream, or other natural area. These sensitive areas are valuable for many reasons and are easily damaged by invasive plants.
- Never throw away unwanted plants or clippings in a nearby park, natural area, or green street planter, or on anyone else’s property. Lots of invasive plants can spread from seeds, berries, or even just a small piece of root or stem.
- Put all old or dead aquarium plants in the trash. Never dump anything from your aquarium outside your home.
Spread the word
- If you see your local nursery selling invasive plants or seeds, let them know about your concerns. Most want to avoid problem plants and will listen.
- If you see an invasive plant on a neighbor’s property, talk with your neighbor about removing it and share some of the resources below.
Resources and plant lists
These resources can help you learn more about plants, how to identify invasive ones, and how to find good alternatives to use in your yard or garden.
- Portland Plant List. The Portland Plant List contains both nuisance plants and native plants. These lists are used in some regulations.
- Portland’s Nuisance Plant List. Nuisance plants may not be planted in certain development situations. In other circumstances, removal of most of these kinds of plants is not legally required, but removal is strongly recommended.
- Oregon Department of Agriculture's Noxious Weed Profiles. The Oregon Department of Agriculture regulates and enforces invasive plant concerns statewide. The department maintains a list of noxious weeds. Refusing to manage important (‘Target’ and/or ‘A-ranked’) plants on this list can result in penalties. Most of the plants on the department’s list are also on Portland’s Nuisance Plant list above.
- Required Eradication List. This list is a small subset of the Nuisance Plants List. Within Portland, these plants must be controlled and permanently removed. Refusing to manage the plants on this list can result in penalties. The City offers help to property owners to manage these plants.
Help Stop Invasive Plants. This poster shows some of the most common invasive plants in our area. These are plants all of us should control as much as we are able in order to keep infestations from becoming larger and more expensive.
Native Plants of the Willamette Valley. Environmental Services’ poster shows some of the Willamette Valley’s native plants. Use this guide to find the right plant for the right place in your yard and garden. Native plants do well in Portland’s weather, so they need less water once established and usually don’t need fertilizers or pesticides.
Find alternatives to invasive plants
- Garden Smart Oregon. This booklet helps identify several types of invasive plants and provides alternative plants to use in your garden or landscape. Adding native plants can bring other advantages, such as food, cover, or nesting sites for all kinds of animals. Find both native and non-native plant alternatives to invasive plants in the Garden Smart.
- Learn how to create landscapes using only native plants through East Multnomah or West Multnomah Soil and Water Conservation Districts.
- Additional organizations with information on alternatives plants for your yard or garden.
- Clackamas Soil & Water Conservation District
- Tualatin Multnomah Soil & Water Conservation District
- Backyard Habitat Certification (Columbia Land Trust + Portland Audubon). Consider getting your yard certified by the Back-yard Habitat Certification Program.
You can get more involved to help stop the spread of invasive plants. Find volunteer opportunities and more information about efforts around the region with the organizations below.