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King County, Washington noxious weed identification and control

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Regulated Class A noxious weeds, 2013 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 (external link) Spartina densiflora
cordgrass, salt meadow Spartina patens
cordgrass, smooth Spartina alterniflora
dyers woad Isatis tinctoria
eggleaf spurge (external link) Euphorbia oblongata
false brome Brachypodium sylvaticum
floating primrose-willow (external link) Ludwigia peploides
flowering-rush Butomus umbellatus
French broom Genista monspessulana
garlic mustard Alliaria petiolata
giant hogweed Heracleum mantegazzianum
goatsrue Galega officinalis
hawkweed, European Hieracium sabaudum
hawkweed, yellow devil (external link) Hieracium floribundum
hydrilla Hydrilla verticillata
johnsongrass (external link) 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 (external link)  Solanum elaeagnifolium
Spanish broom Spartium junceum
spurge flax (external link)  Thymelaea passerina
Syrian bean-caper Zygophyllum fabago
Texas blueweed Helianthus ciliaris
thistle, Italian (external link)  Carduus pycnocephalus
thistle, milk Silybum marianum
thistle, slenderflower Carduus tenuiflorus
variable-leaf milfoil Myriophyllum heterophyllum
velvetleaf Abutilon theophrasti
wild four o'clock (external link) 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.