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Baby’s Breath

Gypsophila paniculata

Baby’s breath is very invasive in BC. When Baby’s breath invades grazing land, it reduces native grasses and forage for grazing animals and wildlife. When it develops seeds and matures, the plant breaks off at the ground and rolls long distances across the landscape with the ability to spread the over 10,000 seeds per plant!

Bachelor’s Buttons

Centaurea cyanus

Also known as cornflower, Bachelor’s button is common in “wildflower” mixes. This invasive plant produces large amounts of seed and can easily invade dry meadows, fields, and grasslands.

Blueweed

Echium vulgare
Warning

Blueweed is a noxious weed throughout BC. It is toxic to horses and cattle and thereby reduces forage quality in rangelands and pastures, resulting in economic losses.

Bohemian Knotweed

Reynoutria x bohemica
Warning

Bohemian knotweed is a hybrid between Japanese and Giant knotweed, and resembles both species. Knotweeds were introduced to British Columbia for use in gardens and landscaping due to their rapid growth and attractive appearance. There are now four species established in BC: Bohemian, Giant, Himalayan, and Japanese knotweed.

Bur Chervil

Anthriscus caucalis

Bur chervil is considered a noxious weed throughout BC. It can be found in most growing conditions, particularly in moist areas such as ditches and fields. Bur chervil easily out-grows native vegetation.

Burdock

Arctium minus

Burdock is known for its clinging burrs that attach to the manes and tails of horses, cows, and sheep’s wool. This causes the animal to be unhealthy and can lowers the market value of the animal. It is considered a noxious weed in many regions of the province.

Butterfly Bush

Buddleja davidii

Butterfly bush is a semi-evergreen shrub that grows up to 5 m tall. This attractive, fast growing plant has escaped gardens and now rapidly spreads into disturbed, open areas and along coastal forest edges, roadsides, and especially on sunny stream edges and riverbanks where it replaces native plants.

Canada Thistle

Cirsium arvense

Canada thistle, despite its common name, is native to Europe and N. Asia. It spreads by its creeping roots. Plants form thick infestations that crowd out forage grasses in pastures and rangelands, reducing crop yields and production.

Common Bugloss

Anchusa officinalis

Common bugloss invades disturbed areas such as pastures and hay fields, which reduces the yield of these crops. It is considered regionally noxious in the Kootenay-Boundary region.

Common Comfrey

Symphytum officinale
Warning

Common comfrey is a popular perennial for herb and permaculture gardens, but it is a weedy pest that is extremely difficult to eradicate! It has large, pointed oval leaves and purple or white flowers that hang like bluebells.

Common Periwinkle

Vinca minor

Common periwinkle was an ornamental groundcover popular for its fast growth, dense coverage, shiny evergreen leaves, and showy purple flowers. However, it has since escaped captivity and become a pest in forests, choking out native plant species.

Common Tansy

Tanacetum vulgare
Warning

Common tansy is often found growing in sunny, disturbed areas such as roadsides or pastures. It is considered a noxious weed in the may regions of BC.

Cypress Spurge

Euphorbia cyparissias
Warning

Cypress spurge was grown as an ornamental but has since escaped into the wild. It prefers sun but tolerates shade as well. It can be found growing in open, disturbed sites like meadows, pastures, and roadsides.

Daphne (Spurge-Laurel)

Daphne laureola
Warning

Daphne was a popular ornamental in gardens at one time due to its glossy, rhododendron-like leaves and fragrant flowers. It is tolerant of both sun and shade and rapidly takes over native vegetation by forming dense thickets in a range of ecosystems.

Diffuse Knapweed

Centaurea diffusa

Diffuse knapweed plants can produce up to 18,000 seeds per year that can remain dormant in the soil for a long time. Seeds can be spread by wind, livestock, and people.

English Holly

Ilex aquifolium
Warning

English holly is known for its shiny berries and dark green, spiny evergreen leaves. English holly has become a serious invasive because of its adaptability to grow in shade or sun, and how easy its seeds are spread by birds.

English Ivy

Hedera helix

English ivy is commonly planted to provide quick cover for walls and buildings, and as ground cover in commercial landscapes. Unfortunately, it quickly forms a dense mat that suppresses native plants.

Eurasian Watermilfoil

Myriophyllum spicatum

Eurasian watermilfoil is an aquatic plant which has been let loose from aquariums. It can quickly take over waterways, causing sluggish water that attracts mosquitos and reduces the recreational potential of the waterway such as swimming and boating.

Field Scabious

Knautia arvensis

Field scabious crowds out forage and pasture plants, reducing food availability for grazing animals. It grows along disturbed roadsides throughout the province.

Flowering Rush

Butomus umbellatus

Flowering rush is an aquatic perennial with green, grass-like foliage and pink almond-scented flowers. It can be difficult to identify as it resembles several native species, but quickly crowds out other plants. It is considered a noxious weed throughout the province.

Foxglove

Digitalis purpurea
Warning

Foxglove is an extremely abundant exotic species that has naturalized throughout the province, leading many to believe this plant is a BC native! Found growing along roadsides, waste areas, and forests, a single foxglove specimen can produce 5,000 seeds each season. Every part of this plant (including the seeds) is extremely poisonous.

Fragrant Waterlily

Nymphaea odorata

This popular, fragrant aquatic perennial is still sold in garden and pond centers throughout the province despite its potential to invade and destroy our sensitive aquatic ecosystems.

Garlic Mustard

Alliaria petiolata

Garlic mustard is a biennial – in the first year, plants appear as a rosette of green leaves close to the ground; these rosettes remain green through the winter and develop into mature flowering plants the following spring. It is considered a noxious weed throughout the province.

Giant Hogweed

Heracleum mantegazzianum
Warning

Giant hogweed is an invasive plant listed as noxious throughout the province of BC according to the BC Weed Control Act Regulation. Currently it’s found in the Lower Mainland, Fraser Valley, Gulf Islands, and central to southern Vancouver Island.

Giant Knotweed

Reynoutria sachalinensis
Warning

Knotweeds grow aggressively and are very hard to kill. Giant knotweed is the largest of the species, with leaves about twice the size as those found on the other species.

Goldmoss Stonecrop

Sedum acre

This rapidly growing succulent was popular for rock and xeriscape gardens and is also occasionally used as a green roof species for its ability to withstand extreme temperatures and drought. However, this species is quite aggressively growing and overtakes other plants, rapidly spreading by both seed and vegetatively. A single leaf can root and turn into a whole new plant.

Gorse

Ulex europaeus

Gorse is a spiny, perennial evergreen shrub. A mature plant can disperse up to 18,000 seeds per plant, and their seeds are easily distributed by human, environmental, and animal transport. Gorse poses a fire hazard due to its volatile oils. It is considered a noxious weed throughout the province.

Hairy Cat’s-Ear

Hypochaeris radicata
Warning

Originally from the Mediterranean, Hairy cat’s-ear is a perennial that invades pastures, meadows, roadsides, riverbanks, lawns, and disturbed sites.

Himalayan Balsam (Policeman’s Helmet)

Impatiens glandulifera

Himalayan balsam is also known as Policeman’s helmet. Originally from the Himalayan region of South Asia, this plant can take over areas with moist soils, including stream and riverbanks

Himalayan Blackberry

Rubus armeniacus

Himalayan blackberry is valued by humans for its delicious berries; however, it easily invades disturbed sites, pastures, roadsides, streambanks, and forest edges.

Himalayan Knotweed

Polygonum polystachyum
Warning

Knotweeds were introduced to British Columbia for use in gardens and landscaping due to their rapid growth and attractive appearance There are now four species established in BC: Bohemian, Giant, Himalayan, and Japanese knotweed. Knotweeds grow aggressively and are very hard to kill.

Hoary Alyssum

Berteroa incana
Warning

Hoary alyssum spreads quickly through a long season of seed production. Seeds are dispersed by vehicles, equipment, footwear, wildlife, and birds. It can also contaminate hay and is considered a noxious weed in the Kootenay-Boundary region.

Hoary Cress

Cardaria draba

Also known as “white-top”, Hoary cress is a perennial plant that invades open, sunny areas such as hayfields, meadows, and roadsides. It spreads by roots and seeds and crowds out native vegetation. It is considered a noxious weed in parts of BC.

Hound’s Tongue

Cynoglossum officinale
Warning

Hound’s tongue grows on dry, well-drained sites. Each plant can produce 2,000 -4,000 barbed seeds a year that cling to clothing, livestock, and wildlife. It is considered a noxious weed throughout the province.

Japanese Knotweed

Reynoutria japonica
Warning

Knotweeds were introduced to British Columbia for use in gardens and landscaping due to their rapid growth and attractive appearance There are now four species established in BC: Bohemian, Giant, Himalayan, and Japanese knotweed.

Leafy Spurge

Euphorbia esula
Warning

Introduced to BC as a garden plant, Leafy spurge is a perennial that has escaped into natural areas. It can now be found on dry roadsides, fields, grasslands, open forests, and disturbed sites.

Marsh Plume Thistle

Cirsium palustre

Native to Europe, Marsh plume thistle is a biennial that prefers moist to wet, naturally open or disturbed areas. Seeds spread by wind, water, birds, vehicles, and equipment.

Mountain Bluet

Centaurea montana

Mountain bluet is a popular garden perennial, however, it easily escapes gardens and invades natural areas. This plant can self-seed, which makes it difficult to control.

Orange Hawkweed

Hieracium aurantiacum

Originally from Europe, Orange hawkweed can create dense mats that crowd out native plants. Hawkweeds spread quickly through above ground runners, horizontal roots, and seeds.

Oxeye Daisy

Leucanthemum vulgare

Originally from Eurasia, Oxeye daisy was first introduced to North America in seed mixes. It is still commonly sold in many store-bought wildflower mixes and remains popular among gardeners despite its negative impacts.

Purple Deadnettle

Lamium purpureum

Purple deadnettle is native to Europe and a common weed throughout BC. It survives as an annual or biennial. A single plant can produce thousands of seeds which remain viable in the soil for several years. It can also spread via stem and root fragments.

Purple Loosestrife

Lythrum salicaria

Purple loosestrife is a pretty perennial plant that spreads rapidly by seed and root fragments. The tiny seeds are dispersed by wind, mud, moving water, wildlife and humans

Queen Anne’s Lace

Daucus carota

Queen Annes’ lace, also known as wild carrot, is common to roadsides and other disturbed areas. This biennial plant persists in clay soils and can be a threat to recovering grasslands.

Rush Skeletonweed

Chondrilla juncea

Rush skeletonweed is a perennial plant native to Eurasia that invades rangelands, roadsides and disturbed areas. It competes with other plants for soil moisture and nutrients.

Russian Olive

Elaeagnus angustifolia

Russian olive is a short invasive tree that can survive in dry conditions and cold temperatures. It drinks more water than most plants in dry soil settings, therefore it can outgrow and compete with native species.

Scentless Chamomile

Matricaria maritima

Scentless chamomile prefers moist soil conditions. It can produce up to 1,000,000 seeds every year, and the seeds can survive in the soil for up to 15 years. This plant can aggressively take over pastures, grasslands, and other agricultural areas.

Scotch Broom

Cytisus scoparius
Warning

Scotch broom was introduced from the Mediterranean and is an escaped garden plant in Canada. It easily invades sunny, disturbed sites such as rangelands, roadsides, and areas of recent logging.

Scotch Thistle

Onopordum acanthium

Scotch thistle is a biennial or perennial that reproduces through thousands of seeds that can survive in the soil for over 30 years. Seeds can spread with the wind, but also in hay and water, and by attaching to clothing or animal fur.

Smallflower Touch-Me-Not

Impatiens parviflora

Smallflower touch-me-not is a twiggy, branching, fine-textured annual species is often found growing in moist soils such as those around rivers, streams, and wetlands mainly in the Fraser Valley region. It is native to Asia. Although this species prefers moist soils, it is tolerant to a range of sun exposures, soil types, and climates, making it difficult to eradicate.

Spotted Knapweed

Centaurea stoebe
Warning

Spotted knapweed is a prolific seed producer, with individual plants producing up to 140,000 seeds per square metre. Seeds and plant fragments make their way into hay and the undercarriages of vehicles, allowing for new infestations over great distances.

St. John’s Wort

Hypericum perforatum
Warning

This plant is a perennial that grows in dense patches which can crowd out natural plants and reduce the grasses that animals feed on. St. John’s-Wort is found in most of southern BC.

Sulphur Cinquefoil

Potentilla recta

Sulphur cinquefoil is a long-lived perennial native to Eurasia. It invades grasslands, dry open forests, and disturbed sites such as roadsides and rangelands.

Tamarisk

Tamarix chinensis

Tamarisk is a shrub-like tree, also known as ‘salt cedar’. The term ‘salt cedar’ comes from its ability to release salt from its leaves, which prevents the growth of any native vegetation within its range.

Tansy Ragwort

Senecio jacobaea
Warning

Tansy ragwort is a biennial to short-lived perennial that grows in pasturelands and disturbed areas. Seeds are easily transported by wind, soils, human activity, and livestock.

Teasel

Dipsacus fullonum

Teasel is a biennial plant that prefers sunny locations and can grow in a range of wet to dry soils. Spreading through seed dispersal, it typically invades meadows, pastures, roadsides, and disturbed areas.

Tree of Heaven

Ailanthus altissima

Native to China, Tree of Heaven is a deciduous tree that became popular in BC with gardeners for its rapid growth and interesting foliage. It produces by seed and by division and can sprout nearly anywhere, making it very difficult to eradicate!

Wild Caraway

Carum carvi

Wild caraway was introduced to Canada as a spice crop but has escaped cultivation. It is a biennial plant that can quickly outgrow native plants. It can grow in light shade, survive light frost and extra moisture in the soil.

Wild Chervil

Anthriscus sylvestris

Wild chervil is a biennial to short-lived perennial in the Parsley family. It is typically found along roadsides, fencelines, streambanks, in ditches and competing with pasture and hay crops

Yellow Archangel

Lamiastrum galeobdolon

Yellow archangel is a perennial garden plant usually seen in hanging baskets and as a ground cover. This plant prefers shady sites such as forested areas and grows in a dense mat that smothers other native plants. It spreads by seed and plant fragments, and by animals and humans passing through the vegetation.

Yellow Flag Iris

Iris pseudacorus
Warning

Yellow flag iris invades ditches, wetlands, streams, lake shorelines, and shallow ponds. This plant reproduces through seed dispersal, horizontal roots, and when pieces of the roots break off, which can form new plants.

Yellow Floating Heart

Nymphoides peltata

Yellow floating heart is an aquatic perennial native to Eurasia that forms thick mats of vegetation in our sensitive aquatic ecosystem. It resembles a water lily with its round, glossy leaves that float on the water’s surface with yellow flowers attached to sturdy, upright stems. If you see this plant in BC, be sure to report it!

Yellow Loosestrife

Lysimachia punctata
Warning

Yellow loosestrife is a fast-spreading perennial plant native to central Europe and Turkey. It can form dense clumps that spread out over large areas, crowding out native plants.

Yellow Toadflax

Linaria vulgaris

Native to Europe, Yellow toadflax, also known as Common toadflax, spreads by a creeping root system. It is typically found in cultivated fields, pastures, along roadsides and other disturbed areas.