Status of creeping knapweed in Tasmania(Acroptilon repens)
- Creeping knapweed is a declared weed in Tasmania under the Tasmanian Weed Management Act 1999. The importation, sale and distribution of creeping knapweed are prohibited in Tasmania.
- The legal responsibilities of landholders and other stakeholders in dealing with creeping knapweed are laid out in the Creeping Knapweed Statutory Weed Management Plan.
What does creeping knapweed look like?
knapweed is an erect, perennial (long-lived) herb growing from 40 to
100 cm high. The stems are covered with dense soft grey hairs, while the
leaves are silvery to greyish green and slightly hairy. The rosette
leaves (leaves in a whorl close to the ground) are shortly stalked,
lobed and toothed, while the stem leaves are only slightly toothed or
entire and have no stalks. The flower-heads are urn-shaped, made up of
numerous purple, lilac or pink tubular florets, and are born singly on
the ends of branches. Creeping knapweed has an extensive and
rapid-growing, woody root system which gives rise to dense colonies with
many aerial shoots.
- Seeds germinate during winter and summer.
Creeping knapweed remains as a rosette in its first summer, dies back in
autumn, and then produces new growth and flowers in the following
spring and summer.
- Creeping knapweed produces large numbers of
seeds although seedlings are rare. Seed can be spread in contaminated
hay and other seed. Creeping knapweed also spreads via root fragments
being transported by cultivation equipment.
Image top right: creeping knapweed (Image: CDFA)
Image above left: creeping knapweed (Image: Neal Kramer)
Image above right: creeping knapweed (Image: CDFA)
Impacts of creeping knapweed
knapweed is a weed of irrigated crops and cereals, and heavy
infestations of creeping knapweed can greatly reduce crop yields.
Creeping knapweed is thought to be able to grow in a number of areas of
Tasmania, and has the potential to be a very serious agricultural weed
Where does creeping knapweed occur?
- Creeping knapweed originates from the Caspian Sea region, Asia Minor, Afghanistan, and Mongolia.
- Creeping knapweed has established widely on mainland Australia in New South Wales, Victoria, Queensland and South Australia.
- Creeping knapweed has not managed to establish in Tasmania. However it has occasionally been found as a contaminant of imported animal feed grain.
What you need to do
- If you locate
creeping knapweed anywhere in Tasmania, or if you find a plant that you
think could be creeping knapweed, immediately contact your Regional Weed
Management Officer on 1300 368 550 to report this weed.
Creeping Knapweed Statutory Weed Management Plan
Weed Links and Resources
Other useful links
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