King County, WA Invasive Plant Rules: Bamboo Restrictions (2026)

Unincorporated King County has no specific regulation restricting or banning bamboo planting. True bamboo species (Bambusoideae) are not listed on the King County Noxious Weed List, which is maintained by the King County Noxious Weed Control Board under state authority (RCW 17.10). However, the Pacific Northwest's mild, wet climate is highly conducive to running bamboo growth, making it a greater concern here than in arid or extreme-winter climates. Running bamboo species like Phyllostachys can spread rapidly through rhizomes in King County's moist soils. While the county does not regulate bamboo, Washington State civil law provides remedies for bamboo that encroaches on neighboring properties. Under Washington's nuisance law (RCW 7.48), encroaching vegetation that damages property or interferes with use and enjoyment constitutes a private nuisance. Property owners can pursue civil action for removal and damages. Notably, the nearby City of Kirkland (within King County but incorporated) maintains a Prohibited Plant List that restricts certain invasive species in new development, though bamboo is not currently on it. King County's Critical Areas Ordinance (KCC 21A.24) regulates vegetation clearing in critical areas (wetlands, streams, slopes) and may affect bamboo management practices near these sensitive areas. Root barriers (minimum 30 inches deep, 60 mil HDPE) are strongly recommended for anyone planting running bamboo in King County. Clumping bamboo species (Fargesia, which is cold-hardy and well-suited to the Pacific Northwest) are a safer choice.