Invasive Plants

Invasive Plants

Weeds are plants growing in places where they are not wanted. Invasive weeds are non-native plants that can cause harm to the natural environment, humans and animals. The Oregon Department of Agriculture estimates that Oregon spends $81 million annually on the control of invasives species. Weed management is an on-going activity. Weeds that appear to be suppressed may re-emerge. Reducing soil disturbance along with regular monitoring and weed removal are the keys to weed control. 

Pathways and Prevention Weeds are often introduced by human activities. Some weeds (like Himalayan blackberry) are brought in for agricultural purposes, others (like reed canarygrass) may be imported for erosion control, and many (like butterfly bush) have been introduced through the nursery trade. Once present, weeds can be spread by people, birds, wildlife, wind, water, machinery and other means. 

Follow these practices to help limit the spread of invasive weeds on your property and throughout the county: 

• Play, clean, go.

  After working with or walking through weeds, remove any plant parts from your apparel and gear before moving to another area.

• Grow native.

  Use only native or non-invasive species when planting new vegetation.

• Right plant for the right place.

  Carefully choose pond plants to avoid accidentally introducing weedy aquatic species.

• Don’t let it loose.

  Never dump aquarium contents down any drain. Seal in a bag and put in the trash.

• Buy it where you burn it.

  Buy fire wood locally. Weeds and pests can be transported in wood.

• Clean, drain, and dry.

  Clean boats of all vegetation and aquatic life after each use.

Weed Management Strategies

Property owners will benefit greatly from working with neighbors on weed management because of the transient nature of weeds. Be aware that certain weeds require different management strategies to control. Identifying weed threats on your property is the first step to early detection and rapid response. Prevention is the most cost effective line of defense. Keep your property covered with desirable vegetation and make sure not to transport weeds. Use native or non-invasive vegetation to out-compete noxious weeds. 

Quickly respond to any new weed infestation.Common weed control techniques include:

• Physical

  Hand-pulling weeds before they set seed can help stop them from spreading.

• Mechanical

  Mow, rake or use powered tools and machinery to manage weeds. 

• Grazing

  Allow livestock to graze weeds before they go to seed. Since animals can transport seeds, don’t move them from a weedy area to a weed free area. 

• Chemicals

  Herbicides are commonly used to kill weeds. Be sure to read the product label prior to application. Use the weather (e.g., wind direction), buffers or other practices to minimize any transport of chemicals away from the target plant by runoff or drift.

Attend a Weed Pull

Attend a weed pull and learn how to identify native plants and noxious weeds. Join a Love Your River workshop or paddle and weed pull day on the Willamette River, hosted by members of the Willamette Mainstem Cooperative. Or join us at the Let’s Pull Together Event during Oregon’s Invasive Weed Awareness week each spring at one of our local parks to pull weeds from the places we love with members of the Benton County Cooperative Weed Management Area.