Noxious Weeds

Quarantine List

The Washington State Department of Agriculture maintains a quarantine list of plants, also called the prohibited plants list, whose sale or distribution is prohibited in the state. All Class A noxious weeds are on this list. There are also plants on the list to prevent them from being imported and spread in our state. Click here to download a copy of the quarantine list.

 

velvetleaf
Abutilon theophrasti
garlic mustard
Alliaria petiolata
indigobush
Amorpha fruticosa
common bugloss
Anchusa officinalis
wild chervil
Anthriscus sylvestris




 

false brome
Brachypodium sylvaticum
plumeless thistle
Carduus acanthoides
musk thistle
Carduus nutans
Italian thistle
Carduus pycnocephalus
slenderflower thistle
Carduus tenuiflorus




 

purple starthistle
Centaurea calcitrapa
diffuse knapweed
Centaurea diffusa
brown knapweed
Centaurea jacea
meadow knapweed
Centaurea jacea x nigra
spotted knapweed
Centaurea stoebe




 

bighead knapweed
Centaurea macrocephala
black knapweed
Centaurea nigra
Vochin knapweed
Centaurea nigrescens
dwarf snapdragon
Chaenorrhinum minus
common crupina
Crupina vulgaris




 

Scotch broom
Cytisus scoparius
wild carrot
Daucus carota
blueweed
Echium vulgare
leafy spurge
Euphorbia esula
eggleaf spurge
Euphorbia oblongata
coming soon
coming soon
coming soon
coming soon coming soon

 

goatsrue
Galega officinalis
shiny geranium
Geranium lucidum
Texas blueweed
Helianthus ciliaris
giant hogweed
Heracleum mantegazzianum
Venice mallow
Hibiscus trionum
coming soon
coming soon
coming soon
coming soon coming soon

 

orange hawkweed
Hieracium aurantiacum
yellow hawkweed
Hieracium caespitosum
yellow devil hawkweed
Hieracium floribundum
mouseear hawkweed
Hieracium pilosella
European hawkweed
Hieracium sabaudum
coming soon
coming soon
coming soon
coming soon coming soon

 

policeman's helmet
Impatiens glandulifera
dyer's woad
Isatis tinctoria
kochia
Kochia scoparia
perennial pepperweed
Lepidium latifolium
oxeye daisy
Leucanthemum vulgare
coming soon
coming soon
coming soon
coming soon coming soon

 

Dalmatian toadflax
Linaria dalmatica ssp. dalmatica
wild four o'clock
Mirabilis nyctaginea
Scotch thistle
Onopordum acanthium
Japanese knotweed
Polygonum cuspidatum
Himalayan knotweed
Polygonum polystachyum
coming soon
coming soon
coming soon
coming soon coming soon

 

giant knotweed
Polygonum sachalinense
Bohemian knotweed
Polygonum x bohemicum
unicorn-plant
Proboscidea louisianica
kudzu
Pueraria montana var. lobata
Mediterranean sage
Salvia aethiopis
coming soon
coming soon
coming soon
coming soon coming soon

 

meadow clary
Salvia pratensis
clary sage
Salvia sclarea
tansy ragwort
Senecio jacobaea
milk thistle
Silybum marianum
silverleaf nightshade
Solanum elaeagnifolium
coming soon
coming soon
coming soon
coming soon coming soon

 

buffalobur
Solanum rostratum
lawnweed
Soliva sessilis
johnsongrass
Sorghum halepense
Spanish broom
Spartium junceum
saltcedar
Tamarix ramosissima
coming soon
coming soon
coming soon
coming soon coming soon

 

spurge flax
Thymelaea passerina
hedgeparsley
Torilis arvensis
gorse
Ulex europaeus
Syrian bean-caper
Zygophyllum fabago
 
coming soon
coming soon
coming soon
coming soon

Lythrum Quarantine
WAC 16-752-400 - 415

It is prohibited to transport, buy, sell, offer for sale or to distribute plants, plant parts or seeds of Lythrum salicaria or L. virgatum into or within the state of Washington. Also prohibited is transportation of wild plants or plant parts of these species in the state of Wash-ington. This includes hybrid crosses and named cultivars of L. salicaria and L. virgatum.

purple loosestrife
Lythrum salicaria
wand loosestrife
Lythrum virgatum
     
coming soon
coming soon

 

Wetland and Aquatics
WAC 16-752-505

It is prohibited to transport, buy, sell, offer for sale, or to distribute plants or plant parts of these regulated plants, into or within the state of Washington. It is further prohibited to intentionally transplant wild plants and/or plant parts of these species within the state of Washington.

flowering rush
Butomus umbellatus
fanwort
Cabomba caroliniana
Australian swamp stonecrop
Crassula helmsii
Brazilian elodea
Egeria densa
hairy willowherb
Epilobium hirsutum
coming soon
coming soon
coming soon
coming soon coming soon

 

mud mat
Glossostigma diandrum
reed sweetgrass
Glyceria maxima
hydrilla
Hydrilla verticillata
European frog-bit
Hydrocharis morsus-ranae
African elodea
Lagarosiphon major
coming soon
coming soon
coming soon
coming soon coming soon

 

water primrose
Ludwigia hexapetala
floating primrose-willow
Ludwigia peploides
garden loosestrife
Lysimachia vulgaris
marsh dew flower
Murdannia keisak
parrotfeather
Myriophyllum aquaticum
coming soon
coming soon
coming soon
coming soon coming soon

 

variable-leaf milfoil
Myriophyllum heterophyllum
Eurasian watermilfoil
Myriophyllum spicatum
slender-leaved naiad
Najas minor
yellow floating heart
Nymphoides peltata
grass-leaved arrowhead
Sagittaria graminea
coming soon
coming soon
coming soon
coming soon coming soon

 

delta arrowhead
Sagittaria platyphylla
ricefield bulrush
Schoenoplectus mucronatus
smooth cordgrass
Spartina alterniflora
common cordgrass
Spartina anglica
dense-flowered cordgrass
Spartina densiflora
coming soon
coming soon
coming soon
coming soon coming soon

 

salt meadow cordgrass
Spartina patens
water soldier
Stratiotes aloides
water chestnut
Trapa natans
water caltrap
Trapa bicornus
swollen bladderwort
Utricularia inflata
coming soon
coming soon
coming soon
coming soon coming soon

Please Note: This prohibited plant list comprises the most recent and accepted scientific and common names of the prohibited plant species in Washington State. However, the prohibited status also applies to any and all synonyms.