What is saffron thistle?(Carthamus Ianatus)
- Saffron thistle is a weed of pasture and crops.
- Saffron thistle is a declared weed in Tasmania under the Tasmanian Weed Management Act 1999. The importation, sale and distribution of saffron thistle are prohibited in Tasmania.
How to identify saffron thistle
thistle is an annual plant (living for one year) which grows to 90 cm
tall. Saffron thistle belongs to the daisy family and is closely related
to slender and spear thistles.
- Saffron thistle seeds usually
germinate with the onset of autumn rains although some seeds may
germinate in winter and spring. The seedling grows into a rosette (a
whorl of leaves close to the ground) which rarely exceeds 20 cm in
- In spring a single stiff, wiry stem grows from the
centre of the rosette and the rosette leaves wither and disappear. The
stem leaves are very stiff with stout sharp spines at the tip and along
- The stem divides into many branches with each branch
carrying flower buds. The buds are enclosed in large spiny bracts very
similar to the stem leaves. The flowers are slender, bright yellow
florets which are partially hidden by the large bracts, making the
flowers rather inconspicuous. Flowering occurs throughout November and
December. The seed has a small fringe of stiff hairs which adheres to
wool and clothing.
- The plant generally dies during late autumn to early winter. Dead plants may remain standing for many months.
- For help in identifying thistles in Tasmania, see Identifying Thistles in Tasmania and search the Dennis Morris Weeds and Endemic Flora database for saffron thistle illustrations.
If you are still in doubt about the thistle you are dealing with,
contact your Regional Weed Management Officer on 1300 368 550 for help.
Saffron thistle in Tasmania
- Several small infestations of saffron thistle occur in Tasmania (see map). These infestations can usually be traced back to feed-grain imported from mainland states.
thistle is most common in run down pastures, roadsides and waste areas,
particularly in areas of low rainfall and low soil fertility.
thistle competes strongly with crops and the stiff, wiry stems impede
harvesting operations. The seed also contaminates grains and other crop
- In pastures, dense infestations of saffron thistle
impede grazing. Wool from sheep grazing in infested areas may become
contaminated with sharp leaf fragments. Animals grazing in dense saffron
thistle infestations can also suffer injury to their mouths and eyes
from the spines.
Detailed management and control guidelines for saffron thistle can be found in the Saffron Thistle Control Guide. Refer also to Herbicides for Saffron Thistle Control. For further information see Weed Links and Resources.
Saffron Thistle Control Guide
Herbicides for Saffron Thistle Control
Statutory Management Plan for Saffron Thistle
Weed Links and Resources
Other useful links
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