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Spotted knapweed
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Spotted knapweed is a biennial to short lived perennial and considered regionally noxious under the BC Weed Control Act. Currently distributed throughout southern BC. Spotted knapweed first appeared on Vancouver island in 1905 and has established itself quite well with many very large Spotted knapweed showing up on the North Island of late.
Spotted knapweed has hairy, deeply cut leaves and purple flowers on one or more upright stems. The flower heads lower leaves have a black tipped fringe that gives a spotted appearance. Spotted knapweed has a large taproot and can grow to around 1 meter in height.
Spotted knapweed is a big seed producer, with some individual plants producing up to 140,000 seeds per square meter. Seeds and plant fragments make their way into hay and the undercarriages of vehicles, allowing for new infestations over great distances.Spotted knapweed prefers open areas and well drained soils. You can find it growing in grasslands, open forests, and along roadsides. Spotted Knapweed is intolerant to dense shade and prefers moister habitats however.
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