Canada thistle (Cirsium arvense) is a root-creeping perennial. Considered noxious under the BC Weed Control Act, this thistle is commonly found on roadsides, cultivated fields, pastures, logged forests, riverbanks, and other disturbed areas. It is a major concern in the Peace River, Omineca and Skeena areas, and is a widespread throughout the province. Canada thistle has purple or white flowers, with stalkless, spiny, dark-green leaves, growing to 0.3-2 metres in height at maturity. Canada thistle spreads rapidly through horizontal roots that give rise to large infestation patches nearby and out-competing native plants. Canada thistle develops seeds sparingly and may produce 1,000 to 1,500 seeds per flowering shoot. Best adapted to rich, heavy loam, clay loam, and sandy loam, it grows poorly in shaded conditions, can tolerate saline, wet, or dry soils, but does not tolerate waterlogged or poorly aerated

Himalayan blackberry (Rubus discolor) is mostly a biennial plant, growing on disturbed sites, along roadsides and rights-of-ways, in pastures, along river and stream banks, fresh-water wetlands, riparian areas, forest edges, and wooded ravines. They are currently distributed on the Lower Mainland, Sunshine Coast, Fraser Valley, Gulf Islands, central to southern Vancouver Island, Queen Charlotte Islands, the Okanagan, and the West Kootenay areas. Himalayan blackberry has petite, white or faint pink flowers with 5 petals, arranged in clusters of 5-20. Flower stalks are prickly, with robust stems (canes) that support large, flattened and hooked or straight prickles. Canes grow up to 3 metres in height and 12 metres in length at maturity. Evergreen leaves are predominantly large, rounded or oblong, and generally grouped in fives on first-year canes and threes on second year, flowering canes. Fruits are up to 2 cm

  (Centaurea biebersteinii) & (Centaurea diffusa) Spotted (Centaurea biebersteinii) and diffuse knapweed (Centaurea diffusa) are biennial to short-lived perennials, and considered regionally noxious under the BC Weed Control Act. Currently distributed throughout southern BC, both spotted and diffuse knapweed are a major concern in the Omineca, Peace River, Kootenay, Okanagan, Thompson, and Cariboo regions.Diffuse knapweed has hairy, greyish-green, split leaves on many branches growing from a single upright stem. The flowers are white or sometimes purple, with small, sharp, rigid spines on the bracts. Spotted knapweed has hairy, deeply-cut leaves and purple flowers (occasionally white) on one or more upright stems. Flowerhead lower leaves have a black-tipped fringe that gives a spotted appearance. Diffuse and spotted knapweed both have a taproot and grow to around 1 metre in height.Spotted knapweed is a prolific seed producer, with individual plants producing

  (Hieracium spp.) Hawkweeds (Hieracium spp.) are perennial plants with 14 non-native species recorded in BC, and are difficult to identify among the 8 native hawkweed species. One of the 14 non-native species, orange hawkweed (Hieracium aurantiacum) is currently the only hawkweed considered regionally noxious under the Weed Control Act. Most hawkweeds have yellow flowers. Invasive hawkweeds are found throughout most forest regions and regional districts in British Columbia. The regional districts east of the Rocky Mountains, Northern Rockies, and Peace River Regional Districts only have a few known invasive hawkweed sites and efforts to prevent further establishment and spread are actively underway. Orange hawkweed is regionally noxious in the East Kootenay, Central Kootenay, Columbia-Shuswap, Thompson-Nicola, Bulkley Nechako, and Cariboo Regional Districts. Hawkweeds have bright orange, orange-red, or yellow ray flowers with several flower heads in clusters at the

  (Cytisus scoparius) Scotch broom (Cytisus scoparius) is an escaped garden ornamental, common west of the Coast-Cascade Mountains in southwest BC, and is concentrated at the southern end of Vancouver Island. It has also been reported on the Queen Charlotte Islands as well as in parts of the Kootenays and North Okanagan–Shuswap areas.Scotch broom is an evergreen shrub, with bright yellow, pea-like flowers that may have red markings in the middle. Stems are woody and 5-angled, with lower, stalky leaves composed of 3 leaflets and upper, un-stalked leaves. Flat, hairy seedpods are initially green, turning brown or black with maturity. Scotch broom grows to 1-3 metres in height at maturity.Scotch broom spreads by seed and lateral bud growth, and mature plants can produce up to 3500 pods, each containing 5-12 seeds. As seedpods dry they split and spiral, expelling

    (Chondrilla juncea) Rush skeletonweed (Chondrilla juncea) is a perennial and considered noxious under the BC Weed Control Act. Found on rangelands, roadsides, and disturbed habitats at mid-elevations in the dry grassland zone, infestations occur in the Vernon area, Crescent Valley, Kimberley, Windermere, and Creston. It is a major concern in the Kootenay and Okanagan regions.Rush skeletonweed is a mass of wiry, milky fluid-filled stems and small yellow flowers, growing to 1.3 metres in height at maturity. Wiry stems are covered with stiff, reddish-brown hairs at the base. Barely visible narrow leaves give it a “skeleton-like” appearance.Plants can produce 20,000 parachute-like seeds that travel easily with wind, water, animals, and humans along dry grasslands. Horizontal roots also aid reproduction. Rush skeletonweed reduces livestock and wildlife forage, and stems can cause serious problems with harvest machinery.Refer to Weeds BC

   (Euphorbia esula) Leafy spurge (Euphorbia esula) is a perennial, considered noxious under the BC Weed Control Act, and commonly found at low- to mid-elevations on dry roadsides, fields, grasslands, open forests, and disturbed habitats. Isolated pockets occur in the Cariboo, Boundary, East Kootenay, Nechako, and North Okanagan areas. It is a major concern in the Kootenay, Okanagan, Thompson, Cariboo, and Omineca regions.Leafy spurge has clusters of petite, yellowish-green flowers supported by distinctive heart-shaped leaves just below flowers. It is a bushy plant with narrow leaves that spiral around the stem, and grows up to a metre tall with extensive horizontal and vertical roots.Leafy spurge spreads with its extensive root system, which can exceed 4.5 metres horizontally and 9 metres vertically. Up to 300 new buds can form on the roots of a single plant. Seed reproduction also contributes

  (Cirsium Palustre) Marsh plume thistle (Cirsium palustre) is a biennial and considered regionally noxious under the BC Weed Control Act. The majority of sites are located in the central interior. Marsh plume thistle is actively contained and monitored at sites in Coastal BC, near Revelstoke, and Vernon. Marsh Plume thistle is a noxious weed in the Bulkley-Nechako and Fraser-Ft. George Regional Districts.Marsh plume thistle is distinguished from other thistles by its single, slender, un-branched stem with spiny wings. Purple flowers cluster at the end, with spiny, hairy leaves that have prominent woody veins on the underside. Plants grow up to 1.5 metres in height at maturity.Preferring moist to wet, naturally open, or disturbed habitats, marsh plume thistle spreads through wind and water seed dispersal, as well as ingestion and deposit by birds. Plants replace native vegetation in open,

  (Leucanthemum vulgare) Oxeye daisy (Leucanthemum vulgare) is a short-lived perennial, considered regionally noxious under the BC Weed Control Act, and of major concern in the Cariboo, Okanagan, Peace River, Thompson, and Omineca. It occurs at low- to mid-elevations in grasslands and dry to moist forests, and is present in the Kootenays, Lower Mainland, and Vancouver Island.Oxeye daisy has daisy-like flowers at the end of course, slender stems, with lower spoon-shaped leaves. Central yellow disks grow 10-20 milimeters wide and white ray flowers 1-2 centimetres long. The plant can grow up to 1 metre in height at maturity. Oxeye daisy is often confused with the ornamental Shasta daisy, which has larger yellow disk (2-3 cm) and white ray flowers (2-3 cm).Oxeye daisy reproduces by seed and underground stems. A single plant produces 26,000 seeds and dispersal from parent plants