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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)

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

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.