Russian Knapweed  


Regional Noxious. Perennial.
Russian knapweed has upright, branched stems which are covered with soft grey hairs when young. It has flowers with tubular, spikey, pink or purple petals and very noticeable pale green, egg-shaped bracts beneath. Leaves are oblong, becoming smaller at the top of the plant. Mature plants are 45 -100 cm tall.

Russian knapweed reduces the yield and quality of cereal crops and is toxic to horses. Plant extracts have been shown to inhibit the growth of other plants. Once established, Russian knapweed extends in all directions and can cover an area of 3.6 m2 within two years.

Russian knapweed occurs in southern British Columbia east of the Coast-Cascade Mountains in low- to mid-elevation grasslands, forests, pastures, cropland, and riverbanks. It is present in the Kootenay, Okanagan, Thompson, and Peace areas and is a major problem in the Okanagan agricultural region.

Russian knapweed's well-developed root system functions as the major means of propagation and spread.


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