Class B Weeds
Class B noxious weeds are those noxious weeds not native to the state that are of limited distribution or are unrecorded in a region of the state and that pose a serious threat to that region. Control is required of the following weeds in Snohomish County.
| Common Name | Scientific Name |
|---|---|
| alyssum, hoary | Berteroa incana |
| blueweed | Echium vulgare |
| bryony, white | Bryonia alba |
| bugloss, annual | Lycopsis arvensis |
| bugloss, common | Anchusa officinalis |
| camelthorn | Alhagi maurorum |
| chervil, rough | Chaerophyllum temulum |
| chervil, wild | Anthriscus sylvestris |
| cinquefoil, sulfur | Potentilla recta |
| common reed | Phragmites australis |
| fanwort | Cabomba caroliniana |
| fennel, common | Foeniculum vulgare |
| floating heart, yellow | Nymphoides peltata |
| gorse (PDF) | Ulex europaeus |
| hairy willow-herb | Epilobium hirsutum |
| Hanging sedge | Carex pendula |
| Hawkweeds: | nonnative species and hybrids of the Meadow subgenus (Piosella) |
| Himalayan knotweed | Polygonum polystachyum |
| houndstongue | Cynoglossum officinale |
| indigobush | Amorpha fruticosa |
| knapweed, black | Centaurea nigra |
| knapweed, brown | Centaurea jacea |
| knapweed, diffuse | Centaurea diffusa |
| knapweed, meadow | Centaurea gerstlaueri |
| knapweed, Russian | Acroptilon repens |
| knapweed, spotted | Centaurea biebersteinii |
| kochia | Kochia scoparia |
| lesser celandine | Ficara verna |
| loosestrife, garden | Lysimachia vulgaris |
| nutsedge, yellow | Cyperus esculentus |
| parrotfeather | Myriophyllum aquaticum |
| pepperweed, perennial | Lepidium latifolium |
| poison hemlock (PDF) | Conium maculatum |
| policeman's helmet (PDF) | impatiens glandulifera |
| puncturevine | Tribulus terrestris |
| saltcedar | Tamarix ramosissima |
| sandbur, longspine | Cenchrus longispinus |
| shiny geranium | Geranium lucidum |
| skeletonweed, rush | Chondrilla juncea |
| spurge, laurel | Daphne laureola |
| spurge, leafy | Euphorbia esula |
| splurge, myrtle (PDF) | Euphorbia myrsinites |
| starthistle, yellow | Centaurea solstitialis |
| thistle, musk | Carduus nutans |
| thistle, plumeless | Carduus acanthoides |
| thistle, Scotch | Onopordum acanthium |
| toadflax, Dalmation | Linaria dalmatica ssp. dalmatica |
| velvetleaf | Abutilon theophrasti |
| water primrose | Ludwigia hexapetala |