Click on images to enlarge
deeply-lobed leaf with spiny margins (Photo: Sheldon Navie)
uppermost leaves and young flower-head with numerous spiny floral bracts (Photo: Sheldon Navie)
seeds topped with long hairs (Photo: Sheldon Navie)
infestation (Photo: Sheldon Navie)
mature flower-heads (Photo: Sheldon Navie)
close-up of winged stem and leaf bases (Photo: Sheldon Navie)
basal rosette of large lower leaves (Photo: Sheldon Navie)
young plant (Photo: Sheldon Navie)
habit in flower (Photo: Sheldon Navie)
flower-head (Photo: Sheldon Navie)
close-up of flower-head (Photo: Sheldon Navie)
close-up of seedling (Photo: Sheldon Navie)
close-up of seeds with hairs removed (Photo: Steve Hurst at USDA PLANTS Database)
Cirsium vulgare (Savi) Ten.
Carduus lanceolatus L.; Carduus vulgarisSavi
Spear thistle, bank thistle, bird thistle, black thistle, blue thistle, boar thistle, bull thistle, bur thistle, button thistle, common bull thistle, common thistle, Fuller's thistle, green thistle, plume thistle, roadside thistle, Scotch thistle, swamp thistle.
Cirsium vulgare is native to Europe, northern Africa, western Asia, Pakistan and China.
Locations within which Cirsium vulgare is naturalised include Africa and Asia, New Zealand, Australia, USA, Canada, South America, Hawaii and other Pacific islands.
Cirsium vulgare is invasive in parts of Kenya (e.g. Kajiado and Laikipia) and has been introduced to Tanzania and Uganda (A.B.R. Witt pers. obs.).
Habitats include pastures, abandoned fields, fence rows, areas along roadsides and railroads, cut-over woods, and miscellaneous waste areas. This species prefers disturbed areas and is not common in relatively undisturbed natural habitats.
Cirsium vulgare reproduces only by seed. The species has a two year life cycle, flowering and setting seed in the second year. Seeds are short-lived on the soil surface but can persist for many years when they are buried, such as from cultivation activities. Plants can be self-pollinated or insect-pollinated, mainly by long-tongued bees. C. vulgare spreads freely by means of seed which can be dispersed by the wind over a large area.
Cirsium vulgare has medicinal properties and can be used as "survival food" if necessary. However, these uses cannot compensate for this plant's overall negative impacts.
Cirsium vulgare spreads from pastures, crops, waste areas and roadsides into disturbed native grasslands, open woodlands and conservation areas. Overgrazed pastures are susceptible to encroachment, and it can sometimes form dense stands that reduce productivity and stocking levels. The species may also dominate forest clear cuts and reduce growth of tree seedlings.
C. vulgare has been included in the Global Invasive Species Database (GISD 2010). It has been listed as a noxious weed in South Africa (prohibited plants that must be controlled. They serve no economic purpose and possess characteristics that are harmful to humans, animals or the environment) and Hawaii.
The precise management measures adopted for any plant invasion will depend upon factors such as the terrain, the cost and availability of labour, the severity of the infestation and the presence of other invasive species. Some components of an integrated management approach are introduced below.
The best form of invasive species management is prevention. If prevention is no longer possible, it is best to treat the weed infestations when they are small to prevent them from establishing (early detection and rapid response). Controlling the weed before it seeds will reduce future problems. Control is generally best applied to the least infested areas before dense infestations are tackled. Consistent follow-up work is required for sustainable management.
Grazing management can help to reduce the ability of Cirsium vulgare to invade pasture lands. Manipulation of grazing together with sowing of appropriate grasses can help to reduce the densities of this weed.
Regular cutting, cultivation and tilling considerably reduce populations of C. vulgare and should be encouraged. Several herbicides are available for the control of C. vulgare. However, care should be taken to use a selective broadleaf herbicide to keep the competitive grasses intact.
Biological control releases against C. vulgare have been undertaken in many countries with variable success.
Not listed as a noxious weed by the state or governments in Kenya, Tanzania and Uganda.
Henderson, L. (2001). Alien weeds and invasive plants. A complete guide to declared weeds and invaders in South Africa. Plant Protection Research Institute Handbook No. 12, 300pp. PPR, ARC South Africa.
PROTA database. Record display PROTA4U: Cirsium vulgare (Savi) Ten. www.prota4u.org/protav8.asp?h=M4&t=Cirsium,vulgare&p=Cirsium+vulgare#Synonyms. Accessed January 2011.
Agnes Lusweti, National Museums of Kenya; Emily Wabuyele, National Museums of Kenya, Paul Ssegawa, Makerere University; John Mauremootoo, BioNET-INTERNATIONAL Secretariat - UK.
This fact sheet is adapted from The Environmental Weeds of Australia by Sheldon Navie and Steve Adkins, Centre for Biological Information Technology, University of Queensland. We recognise the support from the National Museums of Kenya, Tropical Pesticides Research Institute (TPRI) - Tanzania and Makerere University, Uganda. This activity was undertaken as part of the BioNET-EAFRINET UVIMA Project (Taxonomy for Development in East Africa).
BioNET-EAFRINET Regional Coordinator: [email protected]