Invasive Plant Rules in Washington County, OR (2026)

1 county-level rule, plus city-specific rules for 2 cities in Washington County, Oregon.

Verified from official government sources

Note: These county rules apply to unincorporated areas of Washington County. If you live within an incorporated city, that city's own rules apply: see the city list below.

Prohibited Species

When a development in unincorporated Washington County must install landscaping, the Community Development Code bars using any plant identified on regional or local plant lists as invasive or noxious, alongside separate bans on species with damaging root structures and shadow-casting plants that block a neighbor's solar collector.

Washington County Bans Invasive Landscape Plants

Some Restrictions

Washington County Community Development Code § 407-2.2

407-2.2 Prohibited Materials: Landscaping required by Section 407 shall not include any plant material which: A. Is identified by the Director as having root structures that in their mature state may damage or interfere with the normal use of existing public or private underground electrical lines, cables or conduits, pipes or other underground structures; or public or private sidewalks, curbs,...

Full ordinance details →Official source ↗

Invasive Plant Rules by City in Washington County

2 cities in Washington County have their own invasive plant rules rules. Each link goes to that city's dedicated page with code citations.

HillsboroPop. 106,447

1 verified rule • Prohibited Species

BeavertonPop. 97,494

2 verified rules • Prohibited Species, Tree-of-Heaven Removal

All Washington County ordinances

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