Photo Credit: Colorado State University Weed Science, modified from the original
Common Name: Russian Knapweed Scientific Name: Rhaponticum repens Habitat: roadsides, disturbed areas, farmland, grassland Provincial Designation: Prohibited Noxious Prohibited Noxious weeds are plant species that are designated as "prohibited noxious" in theAlberta weed regulation. Prohibited noxious weeds must be destroyed, meaning all growing parts need to be killed or the plant's reproductive mechanisms need to be rendered non-viable. |
Origin
Russian Knapweed is native to Eastern Europe and Asia and in the early 1900s it was introduced to North America as a contaminant in alfalfa seed.
Legislated Because
This species is a serious concern on rangeland and pastures where it can out-compete desired plants and reduce biodiversity. It is also very toxic to horses.
Description
This purple flowering knapweed has bracts that have a papery, almost translucent tip.
The leaves gradually become smaller up the plant, are grey-green in colour and usually have shallowly lobed edges.
Learn more about this species:
See Fact Sheets - Alberta Invasive Species Council