Noxious Weed Alert

  • Fri Apr 16th, 2021 10:42am
  • News
Before treatment

Before treatment

Spotted Jewelweed

Have you seen this plant??

In October 2019, restoration technicians with 10,000 Years Institute identified and treated 4,000 ft2 of invasive spotted jewelweed (Impatiens capensis) along the Upper Hoh Road east of Canyon Creek.

The Hoh River site is the only known coastal population north of Grays Harbor County and west of the Elwha River. (

Avoid walking on disturbed soil in this location as seeds were likely produced in 2018 and remain present in the soil.

The problem:

Spotted jewelweed is a Class C noxious weed that spreads rapidly in floodplains, wetland edges, and along roadsides. Creating dense carpets, spotted jewelweed outcompetes native plant species and can hybridize with the native spurless jewelweed (Impatiens ecornuta).

Plant Description:

Spotted jewelweed typically grows between 2 to 5 feet tall and flowers from mid-summer to early fall. The red to orange, spotted flowers are about 1 inch long. Once triggered, the seed capsules of spotted jewelweed can expel seeds up to four to six feet.

Early Detection and Rapid Response (ED/RR) is critical in preventing the spread of emerging species.

If you have seen this plant, please contact Raena Anderson, Project Coordinator ([email protected]) or call 360-296-8788.

10,000 Years Institute (360) 301-4306, [email protected] ,

Additional Resources:

WA Noxious Weed Control Board:

US Forest Service:

TOXIC: May cause mild to moderate irritation if ingested.


seedling and plants

seedling and plants