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Select a plant common name (left) or Latin name (right) from the lists below or click on a thumbnail photo to read individual plant information.

Need help identifying your weed? Click here

Orange & yellow flowers

bighead knapweed
common tansy
Dalmatian toadflax
dyer's woad
garden loosestrife
leafy spurge
myrtle spurge
orange hawkweed
perennial sowthistle
rush skeletonweed
Scot's broom
Spanish broom
common St. Johnswort
sulfur cinquefoil
tansy ragwort
Texas blueweed
yellow hawkweed
yellow starthistle
yellow toadflax

Pink & purple flowers

annual bugloss
bittersweet nightshade
black knapweed
brown knapweed
bull thistle
Canada thistle
clary sage
common bugloss
common crupina
diffuse knapweed
herb Robert
meadow clary
meadow knapweed
Mediterranean sage
milk thistle
musk thistle
policeman's helmet
purple loosestrife
purple starthistle
Russian knapweed
Scotch thistle
slenderflower thistle
spotted knapweed
viper's bugloss
vochin knapweed
wild four o'clock

White & green flowers

English ivy
field bindweed
garlic mustard
giant hogweed
giant knotweed
Himalayan knotweed
Japanese knotweed
old man's beard
oxeye daisy
perennial pepperweed
poison hemlock
Spurge Laurel (Daphne laureola)
Syrian bean-caper
wild carrot
yellow nutsedge

Aquatic plants

Brazilian elodea
common cordgrass
dense-flowered cordgrass
Eurasian watermilfoil
floating primrose-willow (Ludwigia peploides)
yellow flag iris
fragrant water lily
reed canary grass
saltmeadow cordgrass
smooth cordgrass
water primrose
yellow floating heart

Related information

Related agencies


Find information on noxious weed identification and control in multiple languages:

Program offices are located at 201 S. Jackson St., Suite 600, Seattle, WA 98104. To contact staff, see the Noxious Weed Control Program Directory, send an email, or call 206-477-WEED (206-477-9333).