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To offer a suggestion or report an error on the King County Noxious Weeds Web site, please contact Sasha Shaw, education specialist.
King County, Washington noxious weed identification and control

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Class A noxious weeds, 2012 list
(eradication required throughout Washington State including King County)

Scientific name Common name
Abutilon theophrasti velvetleaf
Alliaria petiolata garlic mustard
Brachypodium sylvaticum false brome
Butomus umbellatus flowering-rush
Carduus pycnocephalus Italian thistle
Carduus tenuiflorus slenderflower thistle
Centaurea calcitrapa purple starthistle
Centaurea macrocephala bighead knapweed
Centaurea nigrescens Vochin knapweed
Clematis orientalis oriental clematis
Crupina vulgaris common crupina
Euphorbia oblongata eggleaf spurge
Galega officinalis goatsrue
Geranium lucidum shiny geranium
Glyceria maxima reed sweetgrass
Helianthus ciliaris Texas blueweed
Heracleum mantegazzianum giant hogweed
Hieracium floribundum yellow devil hawkweed
Hieracium sabaudum European hawkweed
Hydrilla verticillata hydrilla
Isatis tinctoria dyers woad
Ludwigia peploides floating primrose-willow
Myriophyllum heterophyllum variable-leaf milfoil
Pueraria montana var. lobata kudzu
Salvia pratensis meadow clary
Salvia sclarea clary sage
Salvia aethiopis Mediterranean sage
Schoenoplectus mucronatus ricefield bulrush
Silybum marianum milk thistle
Solanum elaeagnifolium silverleaf nightshade
Solanum rostratum buffalobur
Sorghum halepense johnsongrass
Spartina alterniflora smooth cordgrass
Spartina anglica common cordgrass
Spartina densiflora dense flower cordgrass
Spartina patens salt meadow cordgrass
Spartium junceum Spanish broom
Thymelaea passerina spurge flax
Zygophyllum fabago Syrian bean-caper

King County Noxious Weed List

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Related information

Related agencies

Program offices are located at 201 S. Jackson St., Suite 600, Seattle, WA 98104. To contact a staff member at the King County Noxious Weed Control Program, please call 206-296-0290 or by reach them by email.