donors@natureconservancy.ca Dirty, rotten cheater! © 2020 Nature Conservancy of Canada (NCC) | ™ Trademarks owned by The Nature Conservancy of Canada. In early stages of growth, gray-green leaves are deeply lobed with short, thin, grayish hairs; A single pink to purple flowerhead at end of stem; racts at the base of flower fringed with short hairs and black on the tips; Height up to 6 feet; Video Information. Seeds can be transported in mud and debris. This species is also on the Washington quarantine list (known as the prohibited plants list) and it is prohibited to transport, buy, sell, offer for sale, or to distribute plants or plant parts, seeds in packets, blends or \"wildflower mixes\" of this species, into or within the state of Washington. A rosette of leaves is formed in the first year. There are lots of beautiful native species that attract native butterflies and birds, making your garden twice as beautiful. 1. Its leaves are slightly hairy and decrease in size towards the top of the stem. Russian knapweed is a creeping perennial that reproduces from seed and vegetative root buds. Spotted knapweed seed can also be spread via wildlife and livestock, either on their fur or after being eaten. Invasive plants have major economic impacts. People are the major cause of spotted knapweed spread. Spotted knapweed is native to Europe and Asia. This aggressive weed is capable of out competing both forage and crops, making it a nasty customer for … Spotted Knapweed ( Centaurea stoebe ) QUICK IDENTIFICATION. They reproduce through seeds. Find local MDC conservation agents, consultants, education specialists, and regional offices. Cutting or pulling before flowering can be good for small infestations to stop seed production, but requires many years to completely eliminate. Seeds mixed with soil and mud may be carried by vehicles or other equipment that, in turn, create an ideal seedbed for spotted knapweed establishment ( Sheley et al., 1999b ). For example, it is estimated that Montana loses 4.5 million dollars annually in recreation, forage, and costs related to knapweed control. Spotted Knapweed - Duration: 2:18. It usually bolts in the second year, producing branched stems. They can be spread greater distances in hay, on and through animals, and on vehicles. Peak bud production generally occurs from late June to mid-July, depending on seasonal temperature and rain- fall patterns. The weed is spread readily in hay and on vehicle undercarriages. A taprooted, short-lived perennial named for the spotted bracts immediately below the many lavender flowers. Knapweed is a noxious weed that is often found in ditches, along highways, in waterways and other scrubby areas. Also, infestations can decrease food quantities for wildlife and livestock. Branch. Although spotted knapweed is found in most Canadian provinces and one territory (BC, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Nova Scotia and Yukon), it grows mainly in southwestern Canada. Russian knapweed is one of the most difficult perennial weeds to control. As spotted knapweed seeds mature in late summer and fall, they can be spread on mowing equipment and in infested hay, seed, and gravel, or by hitchhiking on vehicles, other equipment, and even clothing. The effects of most limiting factors are explained. How does spotted knapweed spread? They can also spread by wind and water. A single square foot of spotted knapweed can produce 5,000 seeds, which can remain viable for eight years or more. Report new occurrences of invasive plants to provincial. Native species are also adapted to our climate and often require less rigorous care than exotic species. Call 1-800-392-1111 to report poaching and arson, More Wildflowers, Grasses and Other Nonwoody Plants. 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