Pacific Northwest Invasive Plant Council

Pacific Northwest Noxious Weed List

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Scientific Name Common Name State-Province Rating
Abutilon theophrasti Velvetleaf
  • WA
  • OR
  • BC
  • A
  • B
  • P
Acaena novae-zelandiae Biddy-biddy
  • OR
  • B
Acroptilon repens (Centaurea repens) Russian knapweed
  • WA
  • OR
  • AK
  • BC
  • B
  • B
  • PR
  • R
Aegilops cylindrica Jointed goatgrass
  • WA
  • OR
  • BC
  • C
  • B
  • P
Aegilops ovata Ovate
  • OR
  • A
Aegilops triuncialis Barbed
  • OR
  • A
Agropyron repens Quackgrass
  • OR
  • BC
  • B
  • R
Alhagi maurorum Camelthorn
  • WA
  • B
Alhagi pseudalhagi Camelthorn
  • OR
  • A
Alliaria petiolata Garlic Mustard
  • WA
  • OR
  • A
  • B
Alopecurus myosuroides Blackgrass
  • WA
  • B
Amaranthus retroflexus Redroot Pigweed
  • BC
  • N
Ambrosia artemisiifolia Ragweed
  • OR
  • B
Ambrosia tomentosa Skeletonleaf bursage
  • OR
  • A
Amorpha fruticosa Indigobush
  • WA
  • B
Anchusa arvensis Bugloss, annual
  • WA
  • B
Anchusa officinalis Bugloss, common
  • WA
  • OR
  • BC
  • B
  • B
  • R
Anthriscus sylvestris wild chervil
  • WA
  • BC
  • B
  • R
Arctium spp. Burdock
  • BC
  • R
Artemisia absinthium Absinth wormwood
  • WA
  • C
Asclepias speciosa Showy Milkweed
  • BC
  • N
Avena fatua Wild Oats
  • BC
  • P
Berteroa incana Hoary alyssum
  • WA
  • BC
  • B
  • R
Bidens cernua Nodding Beggar-Ticks
  • BC
  • N
Brachypodium sylvaticum False brome
  • OR
  • B
Bryonia alba White bryony
  • WA
  • B
Buddleja davidii (except hort. varieties in OR) Butterfly bush
  • WA
  • OR
  • B
  • B
Cabomba caroliniana Fanwort
  • WA
  • B
Capsella bursa-pastoris Shepherd's-Purse
  • BC
  • N
Cardaria draba Hoary cress
  • WA
  • C
Cardaria pubescens Hairy whitetop
  • WA
  • C
Cardaria spp. Hoary Cress
  • BC
  • R
Carduus acanthoides Thistle, plumeless
  • WA
  • OR
  • BC
  • B
  • A
  • R
Carduus nutans Nodding Thistle, Musk Thistle
  • WA
  • OR
  • BC
  • B
  • B
  • N
Carduus pycnocephalus Italian thistle
  • WA
  • OR
  • A
  • B
Carduus tenuiflorus Slenderflower Thistle
  • WA
  • OR
  • A
  • B
Carthamus baeticus Smooth distaff
  • OR
  • A
Carthamus lanatus Woolly distaff
  • OR
  • A
Cenchrus longispinus Longspine sandbur
  • WA
  • B
Centaurea calcitrapa Purple star thistle
  • WA
  • OR
  • A
  • A
Centaurea diffusa Knapweed, diffuse
  • WA
  • OR
  • BC
  • B
  • B
  • P
Centaurea iberica Iberian
  • OR
  • A
Centaurea jacea Knapweed, brown
  • WA
  • B
Centaurea macrocephala Bighead knapweed
  • WA
  • A
Centaurea maculosa (C. stoebe) Spotted Knapweed
  • OR
  • AK
  • BC
  • B
  • B
  • P
Centaurea nigra Knapweed, black
  • WA
  • B
Centaurea pratensis (C. jacea x C. nigra) Meadow knapweed
  • WA
  • OR
  • BC
  • B
  • B
  • R
Centaurea solstitialis (C. jacea x C. nigra) Yellow starthistle
  • WA
  • OR
  • BC
  • B
  • B
  • P
Centaurea stoebe Knapweed, spotted
  • WA
  • B
Centaurea virgata Squarrose knapweed
  • OR
  • A
Centraurea nigrescens Short-fringed Knapweed
  • WA
  • A
Chenopodium album Lamb's-Quarters
  • BC
  • N
Chondrilla juncea Rush skeletonweed
  • WA
  • OR
  • BC
  • B
  • B
  • P
Chrysanthemum leucanthemum Oxeye Daisy
  • BC
  • R
Cichorium intybus Chicory
  • BC
  • N
Cicuta douglasii Water Hemlock
  • BC
  • N
Cirsium arvense Canada Thistle
  • WA
  • OR
  • AK
  • BC
  • C
  • B
  • PR
  • P
Cirsium palustre Marsh Plume Thistle
  • BC
  • R
Cirsium vulgare Bull Thistle
  • WA
  • OR
  • BC
  • C
  • B
  • N
Clematis vitalba Old man's beard
  • WA
  • OR
  • C
  • B
Conium maculatum Poison-hemlock
  • WA
  • OR
  • B
  • B
Convolvulus arvensis Field bindweed
  • WA
  • OR
  • AK
  • BC
  • C
  • B
  • PR
  • N
Cortaderia jubata(Lemoine) Jubata grass
  • OR
  • B
Crepis tectorum Narrow-Leaf Hawksbeard
  • AK
Crupina vulgaris Common crupina/Bearded creeper
  • WA
  • OR
  • BC
  • A
  • B
  • P
Cuscuta approximata Smoothseed alfalfa dodder
  • WA
  • C
Cuscuta spp. Dodder
  • OR
  • BC
  • B
  • P
Cynoglossum officinale Houndstongue
  • WA
  • OR
  • BC
  • B
  • B
  • P
Cyperus esculentus Yellow nutsedge
  • WA
  • OR
  • BC
  • B
  • B
  • P
Cyperus rotundus Purple nutsedge
  • OR
  • BC
  • A
  • P
Cytisus scoparius Scotch broom
  • WA
  • OR
  • BC
  • B
  • B
  • N
Cytisus striatus Portuguese
  • OR
  • B
Daphne laureola Spurge laurel
  • WA
  • B
Daucus carota Wild carrot
  • WA
  • B
Dipsacus laciniatus Cutleaf teasel
  • OR
  • B
Echinochloa crusgalli Barnyardgrass
  • BC
  • N
Echium plantagineum Paterson's curse
  • OR
  • A
Echium vulgare Blueweed
  • WA
  • BC
  • B
  • R
Egeria (Elode) densa (Elode) South American waterweed/ Brazilian elodea
  • OR
  • WA
  • B
  • B
Elytrigia repens Quackgrass
  • AK
  •  
Epilobium hirsutum Hairy willow-herb
  • WA
  • C
Equisetum arvense Field Horsetail
  • BC
  • N
Equisetum telmateia Giant horsetail
  • OR
  • B
Euphorbia esula Leafy Spurge
  • WA
  • OR
  • AK
  • BC
  • B
  • B
  • PR
  • P
Euphorbia myrsinites Spurge, myrtle
  • WA
  • OR
  • B
  • B
Euphorbia oblongata Eggleaf Spurge
  • WA
  • A
Fagopyrum tataricum Tartary Buckwheat
  • BC
  • R
Foeniculum vulgare Common fennel
  • WA
  • B
Galega officinalis Goatsrue
  • WA
  • C
Galeopsis tetrahit Hempnettle
  • AK
  • BC
  • PR
  • N
Galium aparine Cleavers
  • BC
  • R
Genista monspessulana French
  • OR
  • B
Geranium robertianum Herb-Robert
  • WA
  • B
Glyceria maxima Reed sweetgrass
  • WA
  • A
Gnaphalium uliginosum Cudweed
  • BC
  • N
Gypsophila paniculata Babysbreath
  • WA
  • BC
  • C
  • N
Halogeton glomeratus Halogeton
  • OR
  • B
Hedera helix (except named hort varieties) English ivy
  • OR
  • B
Hedera helix 'Baltica’, 'Pittsburgh', and 'Star'; H. hibernica 'Hibernica' English ivy - four cultivars only
  • WA
  • C
Helianthus ciliaris Texas blueweed
  • WA
  • OR
  • A
  • A
Hemizonia pungens Spikeweed
  • WA
  • C
Heracleum mantegazzianum Giant Hogweed
  • WA
  • OR
  • BC
  • A
  • A
  • N
Hieracium atratum Hawkweed, polar
  • WA
  • B
Hieracium caespitosum Hawkweed, yellow
  • WA
  • B
Hieracium floribundum Yellow Devil Hawkweed
  • WA
  • OR
  • A
  • A
Hieracium glomeratum Hawkweed, queen-devil
  • WA
  • B
Hieracium lachenalii *Hawkweed, common
  • WA
  • C
Hieracium laevigatum Hawkweed, smooth
  • WA
  • B
Hieracium pilosella Hawkweed, mouseear
  • WA
  • OR
  • B
  • A
Hieracium piloselloides King-devil
  • OR
  • A
Hieracium pratense Meadow
  • OR
  • A
Hieracium spp. Hawkweeds, nonnative and invasive species not listed elsewhere
  • WA
  • C
Hordeum jubatum Foxtail Barley
  • BC
  • N
Hydrilla verticillata Hydrilla
  • WA
  • OR
  • A
  • A
Hyocyamus niger Black henbane
  • WA
  • C
Hypericum perforatum St. Johnswort, common
  • WA
  • OR
  • BC
  • C
  • B
  • N
Hypochaeris radicata Common catsear
  • WA
  • B
Impatiens glandulifera Policeman’s helmet, Himalayan Balsam
  • WA
  • OR
  • BC
  • B
  • B
  • N
Iris pseudacorus Yellow flag iris
  • WA
  • OR
  • C
  • B
Isatis tinctoria Dyers Woad
  • WA
  • OR
  • A
  • B
Juncus effusus Bog Rush
  • BC
  • N
Knautia arvensis Field Scabious
  • BC
  • R
Kochia scoparia kochia
  • WA
  • OR
  • BC
  • B
  • B
  • R
Lamiastrum galeobdolon Yellow archangel
  • WA
  • C
Lamium amplexicaule Henbit
  • BC
  • N
Lepidium chalepensis Lens-podded
  • OR
  • B
Lepidium draba Hoary cress
  • OR
  • B
Lepidium latifolium Perennial pepperweed
  • WA
  • OR
  • BC
  • B
  • B
  • R
Lepidium pubescens Hairy
  • OR
  • B
Lepyrodiclis holosteoides lepyrodiclis
  • WA
  • B
Leucanthemum vulgare (Chrysanthemum leucanthemum) oxeye daisy
  • WA
  • AK
  • B
Linaria dalmatica ssp. dalmatica Dalmatian toadflax
  • WA
  • OR
  • BC
  • B
  • B
  • P
Linaria vulgaris Yellow toadflax, Butter 'n' Eggs
  • WA
  • OR
  • AK
  • BC
  • C
  • B
  • Re
  • P
Ludwigia hexapetala Water primrose
  • WA
  • B
Ludwigia peploides Floating primrose-willow
  • WA
  • A
Lychnis alba White Cockle
  • BC
  • R
Lysimachia vulgaris Loosestrife, garden
  • WA
  • B
Lythrum salicaria Loosestrife, purple
  • WA
  • OR
  • AK
  • BC
  • B
  • B
  • PR
  • R
Lythrum virgatum Loosestrife, wand
  • WA
  • B
Madia glomerata Cluster Tarweed
  • BC
  • N
Malva neglecta Common Mallow
  • BC
  • N
Matricaria maritima Scentless Chamomile
  • BC
  • P
Matricaria matricariodes Pineappleweed
  • BC
  • N
Matricaria perforata Scentless mayweed
  • WA
  • C
Mirabilis nyctaginea Wild Four O’Clock
  • WA
  • A
Myriophyllum aquaticum Parrotfeather
  • WA
  • B
Myriophyllum spicatum Eurasian watermilfoil
  • WA
  • OR
  • B
  • B
Nardus stricta Matgrass
  • OR
  • A
Nymphaea odorata Fragrant water lilys
  • WA
  • C
Nymphoides peltata Yellow floating heart
  • WA
  • OR
  • B
  • A
Onopordum acanthium Scotch Thistle
  • WA
  • OR
  • BC
  • B
  • B
  • R
Orobanche minor Small broomrape
  • OR
  • B
Panicum capillare Witchgrass
  • BC
  • N
Peganum harmala African rue
  • OR
  • A
Phalaris arundinacea Reed canarygrass
  • WA
  • C
Phragmites australis (nonnative genotypes) Common reed
  • WA
  • YT
  • B
  • L
Picris hieracioides Hawkweed oxtongue
  • WA
  • B
Plantago major Broad-Leaved Plantain
  • BC
  • N
Poa annua Annual Bluegrass
  • BC
  • N
Poa compressa Canada blue grass
  • YT
  • Po
Poa pratensis Kentucky blue grass
  • YT
  • Po
Polygonum bohemicums Knotweed, Bohemian
  • WA
  • B
Polygonum convolvulus Wild Buckwheat, Black Bindweed
  • AK
  • BC
  • Re
  • N
Polygonum cuspidatum (Fallopia japonica) Fleece flower / knotweed, Japanese
  • OR
  • WA
  • BC
  • B
  • B
  • N
Polygonum persicaria Lady's-Thumb
  • BC
  • N
Polygonum polystachyum Knotweed, Himalayan
  • WA
  • OR
  • B
  • B
Polygonum sachalinense Knotweed, giant
  • WA
  • OR
  • B
  • B
Potamogeton crispus Curly-leaf pondweed
  • WA
  • C
Potentilla recta Sulfur cinquefoil
  • WA
  • OR
  • BC
  • B
  • B
  • R
Pueraria lobata Kudzu
  • WA
  • OR
  • A
  • A
Rorippa austriaca Austrian fieldcress
  • WA
  • AK
  • B
  • PR
Rorippa sylvestris Creeping yellow cress
  • OR
  • B
Rubus discolor (R. procerus, R. aremeniacus) Himalayan blackberry
  • OR
  • B
Rumex acetosella Sheep Sorrel
  • BC
  • N
Rumex crispus Curled Dock
  • BC
  • N
Sagittaria graminea Grass-leaved arrowhead
  • WA
  • B
Salsola kali Russian Thistle
  • BC
  • R
Salvia aethiopis Mediterranean sage
  • WA
  • OR
  • A
  • B
Salvia pratensis Meadow Clary
  • WA
  • A
Salvia sclarea Clary Sage
  • WA
  • A
Secale cereale Cereal rye
  • WA
  • C
Senecio jacobaea Tansy ragwort
  • WA
  • OR
  • BC
  • B
  • B
  • P
Senecio vulgaris Common groundsel
  • WA
  • BC
  • B
  • N
Setaria viridis Green Foxtail
  • BC
  • R
Silene cucubalus Bladder Campion
  • BC
  • N
Silene latifolia ssp. alba White cockle
  • WA
  • C
Silene noctiflora Night-Flowering Catchfly
  • BC
  • R
Silybum marianum Milk thistle
  • WA
  • OR
  • A
  • B
Sinapsis arvensis Wild Mustard
  • BC
  • R
Solanum elaeagnifolium Silverleaf Nightshade
  • WA
  • OR
  • A
  • A
Solanum rostratum Buffalobur
  • WA
  • OR
  • A
  • B
Solanum species Nightshade
  • BC
  • N
Soliva sessilis Lawnweed
  • WA
  • A
Sonchus arvensis ssp. arvensis Perennial sowthistle
  • WA
  • AK
  • BC
  • B
  • PR
  • P
Sonchus asper Spiny Annual Sow-thistle
  • BC
  • N
Sonchus oleraceus Annual Sowthistle
  • BC
  • P
Sorghum halepense Johnsongrass
  • WA
  • OR
  • A
  • B
Spartina alterniflora Cordgrass, smooth
  • WA
  • B
Spartina anglica Common
  • OR
  • A
Spartina densiflora Dense-flowered cordgrass
  • WA
  • OR
  • A
  • A
Spartina patens Saltmeadow Cordgrass
  • WA
  • OR
  • A
  • A
Spartium junceum Spanish broom
  • WA
  • OR
  • A
  • B
Spergula arvensis Corn Spurry
  • BC
  • N
Sphaerophysa salsula Swainsonpea / Austrian peaweed
  • WA
  • OR
  • B
  • B
Stellaria media Common Chickweed
  • BC
  • N
Taeniatherum caput-medusae Medusahead rye
  • OR
  • B
Tamarix ramosissima Saltcedar
  • WA
  • OR
  • B
  • B
Tanacetum vulgare Common tansy
  • WA
  • BC
  • C
  • R
Thlapsi arvense Stinkweed
  • BC
  • N
Thymelaea passerina Spurge Flax
  • WA
  • A
Tragopogon dubiusa Western Goat's-Beard
  • BC
  • N
Trapa natans European water chestnut
  • OR
  • A
Tribulus terrestris Puncturevine
  • WA
  • OR
  • BC
  • B
  • B
  • R
Tussilago farfara Coltsfoot
  • OR
  • A
Ulex europaeus Gorse
  • WA
  • OR
  • BC
  • B
  • B
  • P
Verbascum thapsus Mullein
  • BC
  • N
Vicia cracca Tufted Vetch, Bird Vetch
  • AK
  • PR
Xanthium spinosum Spiny cocklebur
  • WA
  • OR
  • C
  • B
Zygophyllum fabago Syrian bean-caper
  • WA
  • OR
  • A
  • A

Abbreviations:

  • British Columbia (BC)
    • P = Provincial – Noxious within all Regions of British Columbia
    • R = Regional – Noxious within the boundaries of certain regional districts
    • N = Nuisance – Weeds not regulated by the BC Weed Control Act
  • Alaska (AK)
    • PR = Prohibited and restricted noxious weeds
    • Re = Restricted
  • Washington State (WA)
    • Class A = Non-native species that are limited in distribution in Washington. State law requires that these weeds be eradicated.
    • Class B = Non-native species that are either absent from or limited in distribution in some portions of the state but very abundant in other areas. The goals are to contain the plants where they are already widespread and prevent their spread into new areas.
    • Class C = Non-native plants that are already widespread. Counties can choose to enforce control, or they can educate residents about controlling these noxious weeds.
  • Oregon State (OR)
    • A Designated = a weed of known economic importance which occurs in the state in small enough infestations to make eradication or containment possible; or is not known to occur, but its presence in neighboring states make future occurrence in Oregon seem imminent.
    • B Designated = a weed of economic importance which is regionally abundant, but which may have limited distribution in some counties.
    • T Designated = a priority noxious weed designated by the Oregon State Weed Board as a target on which the Oregon Department of Agriculture will develop and implement a statewide management plan. “T” designated noxious weeds are species selected from either the “A” or “B” list.
  • Yukon Territories (YT)
    • L= low level invasive
    • Po=potentially invasive
    • H= high invasive