Knowledgebase
Recommendations for contractors with knotweed removal experience? #930620
Asked May 04, 2026, 8:45 PM EDT
Benton County Oregon
Expert Response
Thanks for reaching out. OSU Extension doesn’t maintain or endorse a list of specific contractors, but you can find licensed professionals through Oregon’s official state directories. These tools allow you to verify both landscape construction licenses (for heavy equipment work) and pesticide applicator licenses (required for herbicide use on knotweed).
1. Optional: Oregon Landscape Contractors Association (industry directory)
This is a voluntary membership directory—useful for finding local contractors, but always verify licenses using the state tools above.
https://www.oregonlandscape.org
Licensed through the Oregon Landscape Contractors Board (LCB).
Use the “Verify a License” search tool here: https://www.oregon.gov/lcb/pages/index.aspx
Licensed through the Oregon Department of Agriculture (ODA).
Use the statewide pesticide license lookup here: https://mylicense.oda.state.or.us/ords/f?p=250:9:::NO:9:P9_PROGRAM:80
(This is the official ODA database where you can filter by county—select Benton County—and by license category such as Right‑of‑Way, Aquatic, or Ornamental & Turf – Herbicide.)