Ministry of Agriculture

B.C. Weed Control Act
Noxious Weeds in B.C.

Updated August 8, 2011

Noxious weeds are typically non-native plants that have been introduced to British Columbia without the insect predators and plant pathogens that help keep them in check in their native habitats. For this reason and because of their aggressive growth, these alien plants can be highly destructive, competitive and difficult to control.

The B.C. Weed Control Act imposes a duty on all land occupiers to control designated noxious plants.

The purpose for the Act is to protect our natural resources and industry from the negative impacts of foreign weeds.

The following weeds are classified as noxious within all regions of British Columbia:

  • Annual Sowthistle (Sonchus oleraceus)
  • Bohemian Knotweed (Fallopia x bohemica)
  • Bur Chervil (Anthriscus caucalis)
  • Canada Thistle (Cirsium arvense)
  • Common Reed (Phragmites australis subsp. australis)
  • Crupina (Crupina vulgaris)
  • Dalmatian Toadflax (Linaria dalmatica)
  • Dense-flowered Cordgrass (Spartina densiflora)
  • Diffuse Knapweed (Centaurea diffusa)
  • Dodder (Cuscuta spp.)
  • English Cordgrass (Spartina anglica)
  • Flowering Rush (Butomus umbellatus)
  • Garlic Mustard (Alliaria petiolata)
  • Giant Hogweed (Heracleum mantegazzianum)
  • Giant Knotweed (Fallopia sachalinensis)
  • Giant Mannagrass / Reed Sweetgrass (Glyceria maxima)
  • Gorse (Ulex europaeus)
  • Himilayan Knotweed (Polygonum polystachyum)
  • Hound's-tongue (Cynoglossum officinale)
  • Japanese Knotweed (Fallopia japonica)
  • Jointed Goatgrass (Aegilops cylindrica)
  • Leafy Spurge (Euphorbia esula)
  • Milk Thistle (Silybum marianum)
  • North Africa Grass (Ventenata dubia)
  • Perennial Sowthistle (Sonchus arvensis)
  • Purple Loosestrife (Lythrum salicaria)
  • Purple Nutsedge (Cyperus rotundus)
  • Rush Skeletonweed (Chondrilla juncea)
  • Saltmeadow Cordgrass (Spartina patens)
  • Scentless Chamomile (Matricaria maritima)
  • Smooth Cordgrass (Spartina alterniflora)
  • Spotted Knapweed (Centaurea maculosa)
  • Tansy Ragwort (Senecio jacobaea)
  • Velvetleaf (Abutilon theophrasti)
  • Wild Oats (Avena fatua)
  • Yellow Flag Iris (Iris pseudacorus)
  • Yellow Nutsedge (Cyperus esculentus)
  • Yellow Starthistle (Centaurea solstitialis)
  • Yellow Toadflax (Linaria vulgaris)

The following weeds are classified as noxious within the boundaries of the corresponding regional districts:

BlueweedEchium vulgareCariboo, Central Kootenay, Columbia-Shuswap, East Kootenay, Okanagan-Similkameen, Thompson-Nicola
BurdockArctium spp.Bulkley-Nechako, Cariboo, Columbia-Shuswap, Fraser-Fort George, Kitimat-Stikine, North Okanagan, Okanagan-Similkameen, Peace River, Thompson-Nicola
CleaversGalium aparinePeace River
Common Bugloss Anchusa officinalis Kootenay-Boundary
Common TansyTanacetum vulgareBulkley-Nechako, Central Kootenay, Columbia-Shuswap, East Kootenay, North Okanagan
Field ScabiousKnautia arvensisBulkley-Nechako, Kootenay-Boundary,  Thompson-Nicola
Green FoxtailSetaria viridisPeace River
Hoary Alyssum Berteroa incana Kootenay-Boundary
Hoary CressCardaria spp.Columbia-Shuswap, North Okanagan, Thompson-Nicola
KochiaKochia scopariaPeace River
Marsh Plume Thistle Cirsium palustre Bulkley-Nechako, Fraser-Fort George
Meadow KnapweedCentaurea pratensisColumbia-Shuswap
Night-Flowering CatchflySilene noctifloraPeace River
Orange HawkweedHieracium aurantiacumBulkley-Nechako, Cariboo, Central Kootenay, Columbia-Shuswap, East Kootenay, Thompson-Nicola
Oxeye DaisyChrysanthemum leucanthemumCariboo, North Okanagan, Peace River, Thompson-Nicola
Perennial PepperweedLepidium latifoliumEast Kootenay, Thompson-Nicola
Plumeless ThistleCarduus acanthoidesCentral Kootenay
PuncturevineTribulus terrestrisOkanagan-Similkameen
Purple LoosestrifeLythrum salicariaComox-Strathcona (by regional district bylaw)
QuackgrassAgropyron repensPeace River
Russian KnapweedAcroptilon repensNorth Okanagan
Russian ThistleSalsola kaliPeace River
Scotch ThistleOnopordum acanthiumNorth Okanagan
Sulphur CinquefoilPotentilla rectaColumbia-Shuswap, North-Okanagan, Okanagan-Similkameen, Thompson-Nicola
Tartary BuckwheatFagopyrum tataricumPeace River
White CockleLychnis albaPeace River
Wild ChervilAnthriscus sylvestrisFraser Valley
Wild MustardSinapsis arvensisPeace River

More Information on Noxious Weeds