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Is Japanese knotweed illegal in Oregon?

Japanese knotweed is a legally regulated plant in Oregon.Legally regulated — restrictions apply: On an official noxious-weed / regulated list. What is restricted (movement, control, sale with conditions) depends on the exact wording below.
Sources (3)

Also called: Reynoutria (Fallopia) japonica. Last checked against official sources: 2026-10-14.

Federal noxious weed list (7 CFR 360.200): Japanese knotweed is not listed.

What Oregon's official list says

List / legal categoryListed asList noteWhat it means
"B" noxious weed (OAR 603-052-1200 quarantine)Fallopia japonica (Polygonum)Japanese knotweedLegally regulated — restrictions apply

Effective dates

Already have it in your yard?

Noxious-weed rules can require control or restrict moving the plant (including soil, seed and cuttings). Check the exact wording above and the linked law.

Native alternatives for Oregon

Each is recorded as native to Oregon in the USDA NRCS PLANTS Database state distribution (retrieved 2026-10-14). Check size, sun and soil fit for your site with your local Extension office.

Japanese knotweed in other states

Alabama California Colorado Connecticut Delaware Idaho Illinois Indiana Kentucky Maine Massachusetts Michigan Minnesota Montana Nebraska New Hampshire New York Ohio Pennsylvania Utah Vermont Virginia Washington West Virginia Wisconsin

See every plant on Oregon's invasive & noxious plant lists, or check any plant.

Not legal advice. PlantLegit summarizes official lists and links the source. Laws change, local (county/city) rules may add restrictions, and the official text controls. "What it means" is our plain-English label; read the exact list wording. Confirm with the agency before buying, selling or removing plants. Full disclaimer.