08/19/2026
🌿 Invasive W**d Wednesday: Knotw**d 🌿
Knotw**d is an aggressive invasive w**d that forms dense stands, outcompeting native vegetation, and degrading wildlife habitat. Knotw**d is found in riverbanks and stream areas, along roadsides, gardens, and waste areas. It is very difficult to control it once it’s established, because it primarily spreads through rhizomes. Even the smallest root fragments can allow knotw**d to resprout and take over areas.
Himalayan Knotw**d is a Class B-designated w**d in Clallam County, meaning controlling infestations and preventing the spread of all propagules is required. Japanese, giant, and Bohemian knotw**d are all selected w**ds, meaning control of these w**ds is required within the riparian and flood zones of Big, Clallam, Ennis, Hoko, and Sekiu Rivers and their tributaries; and along roadsides and in soil, mulch, or mineral mining storage areas.
How to identify Japanese knotw**d (knotw**d species are similar, but there are some differences between species; please refer to https://www.nwcb.wa.gov/.)
• Have reddish-brown stems.
• Leaves are alternately arranged, being ovate-shaped.
• Flowers are whitish- whitish-green, forming clusters
• Fruit is shiny brown and triangular
• Plants can grow to 4-8 feet
For more information and ID assistance, please visit WA State Noxious W**d Control Board’s website: (https://www.nwcb.wa.gov/w**ds/japanese-knotw**d). If you would like control recommendations, please contact the Clallam County Noxious W**d Control Board at 360-417-2442 or email web_w**[email protected]. Contact Clallam Conservation District if seeking native plant recommendations.
Together, we can help protect Clallam County’s landscapes from invasive w**ds!
Photos courtesy of Washington State Noxious W**d Control Board. Images are of Japanese knotw**d.
