An alien species is a non-native species whose interaction causes economic harm, harm to human health and/or environmental harm. Invasive species are often likened to



These "super-weeds" have abilities to reproduce and survive that far exceed their native counterparts. Invasive plants quickly displace native vegetation and completely take over sensitive ecosystems as they have no natural predators (i.e. diseases, fungi, insects) in their non-native environment.



Location: Lower Mainland, Fraser Valley, Gulf Islands, and central to southern Vancouver Island


Status: At Large in British Columbia



• Numerous small white flowers clusters in an umbrella-shaped head

• Dark green leaves are coarsely toothed in 3 large segments with stiff underside hairs

• Lower leaves can exceed 2.5 metres in length.

• Can grow up to 5 metres in height at maturity.


Wanted for: Giant hogweed stem hairs and leaves contain a clear, highly toxic sap that, when in contact with the skin, can cause burns, blisters and scarring.


Notes: WorkSafe BC has issued a Toxic Plant Warning for Giant hogweed



Location: Eastern seaboard of the United States, Nova Scotia, New Brunswick, Quebec, Ontario, and British Columbia.


Status: At Large across Canada



• Small red to brownish red ant

• Two waist segments

• Two backward pointing spines and stinger (visible with a magnifying glass)


Wanted for: Fire ant is an aggressive, swarming ant that can deliver a painful sting when disturbed.


Notes: Once established, the colonies also spread naturally through "colony budding", where one or more queens and a group of workers will leave the colony and establish a new satellite colony.




Location: Cariboo, Central Kootenay, Columbia-Shuswap, East Kootenay, Okanagan-Silmilkameem, and Thompson-Nicola Regional Districts.


Status: At Large



• Bright blue blossoms

• Rough stems,

• Grow 30-80 centimetres in height at maturity


Wanted for: Infestations are associated with some economic losses.


Notes: Seeds are generally dropped in the immediate vicinity of the parent plant, but can be distributed further by animals as the rough seeds stick to clothing, hair and feathers.



Location: Mussels have been found in the Great Lakes in Ontario and Quebec, and in at least 24 American states as far west as California and Colorado. Currently Zebra and quagga mussels have not become established in Oregon, Idaho, Washington, Montana or British Columba.


Status: Growing in numbers



• Grow up to 15 mm

• A “D-shaped” shell

• Lower leaves can exceed 2.5 metres in length.

• Colour may vary from light to dark brown and the shell has obvious striping


Wanted for: Threat to the biodiversity and fisheries of any water system


Notes: Invasive mussels can colonize on boats and other watercraft.



Location: Invasive hawkweeds are found throughout most forest regions and regional districts in British Columbia.


Status: At large in British Columbia



• Bright orange, orange-red, or yellow ray flowers with several flower heads

• Leaves are long and oval-shaped

• Stems contain a milky fluid

• rosette formation at the base of fibrous


Wanted for: Hawkweeds can replace native vegetation in open, undisturbed natural areas such as meadows, reducing forage and threatening biodiversity.


Notes: Hawkweeds (Hieracium spp.) are perennial plants with 14 non-native species recorded in BC.



Location: West of the Coast-Cascade Mountains in southwest BC, and is concentrated at the southern end of Vancouver Island


Status: At in British Columbia



• Bright yellow, pea-like flowers

• Stems are woody and 5-angled

• Flat, hairy seedpods are initially green, turning brown or black with maturity


Wanted for: Scotch Broom invades rangelands, replacing forage plants, and is a serious competitor to conifer seedlings.


Notes: Photosynthetic stems enable year-round growth, leading to displacement of native plant species.



Location: BC’s southern interior, and has quickly spread throughout the Okanagan valley, lower Similkameen valley, Christina Lake and other isolated sites in the West Kootenays.


Status: At large in British Columbia



• Yellow flowers with 3 sepals that curve backward

• 3 petals pointing upwards

• Leaves fold and clasp the stem at the base in a fan-like fashion


Wanted for: While seeds disperse in the wind and water, popularity of the plant in the market exacerbate efforts to contain new infestations.


Notes: Yellow flag-iris can sicken livestock if ingested, though it is generally avoided by grazing animals. Contact with the resins can cause skin irritation in humans.



Location: Just about anywhere including driveways, gardens, roads, ditches, creeks


Status: At Large in British Columbia



• Hollow, bamboo-like stems

• Distinct red coloured segments along the    stems

• Small white flowers

• Large green leaves

• Grows to 3m tall


Wanted for: Extensive damage to private

and public property and wreaking havoc on the environment


Notes: Spreads by roots, seeds and

plant fragments.





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