Washington County, OR Landscaping Rules: Weed Ordinances (2026)
Key Facts
- Declared nuisance
- Uncontrolled weeds, brush or grass
- Named species
- Canada thistle, ragweed, Tansy ragwort, gorse
- Abatement notice period
- 15 days
- Max fine
- $500 ($1,000 repeat within 2 yrs)
- Enforcing agency
- Washington County Health Department
- Code section
- Washington County Code § 8.20.030(A)(9)
Summary
Uncontrolled weeds, brush or grass on unincorporated property is a declared nuisance under county code: the health department can order it cut within 15 days, and specifically names noxious weeds like Canada thistle, ragweed and gorse.
A.It shall be unlawful for any owner or person in charge of property to maintain or allow to exist, the following things, practice, or conditions on his property, which are declared to be nuisances:...9.Uncontrolled or uncultivated growth of weeds, brush or grass, including but not limited to Jimson, Burdock, Ragweed, Thistle, White Top, Russian Knapweed, Canadian Thistle, Tansy Ragwort or Gorse (also known as Irish Broom or Furze), or any plant which provides vector harborage or is obnoxious to agriculture or contributes noxious pollens into the atmosphere or creates a fire hazard.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Community Development Code: Supplement 2 | Code of Ordinances: Supplement 25).
Full Breakdown
Washington County Code § 8.20.030(A)(9) declares it a nuisance to maintain or allow "uncontrolled or uncultivated growth of weeds, brush or grass" on property in the unincorporated area, naming Jimson weed, burdock, ragweed, thistle, white top, Russian knapweed, Canadian thistle, Tansy ragwort and gorse (Irish broom/furze) among the covered growth, along with any plant that harbors vectors, is obnoxious to agriculture, spreads noxious pollen, or creates a fire hazard. The health department enforces the chapter (§ 8.20.040) and may inspect at any reasonable hour (§ 8.20.070), including after a complaint signed by five or more residents in the area (§ 8.20.080).
Once the health officer finds the nuisance, § 8.20.090 requires written notice describing the property and the overgrowth and demanding abatement within 15 days; § 8.20.100 allows immediate abatement if the growth is an extreme hazard. A property owner can request a Board of County Commissioners hearing within five days of the notice (§ 8.20.110). If the owner never mows or clears the growth, the county can do it and bill the owner for the direct cost plus a 25% administrative surcharge under § 8.20.140, and place a lien on the property if the bill goes unpaid (§ 8.20.160).
Convicted violators face a fine of up to $500 (§ 8.20.210), with each day of continued overgrowth a separate offense, rising to $1,000 for a second conviction within two years.
Violations & Fines
Ignoring the 15-day abatement notice exposes the owner to a fine of up to $500 per § 8.20.210, with each additional day of overgrowth a new offense, and up to $1,000 for a repeat violation within two years. The county may also mow or clear the property itself and bill the owner for the cost plus a 25% surcharge, filing a lien if unpaid.
Frequently Asked Questions
How tall can weeds or grass get before it's a violation in unincorporated Washington County?
How much notice do I get before I have to cut overgrown weeds?
Can neighbors force an inspection of an overgrown lot?
What if I don't clear the weeds myself?
Sources & Official References
Other rules in Washington County
Compare Washington County to another location·View the Oregon landscaping rules overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.