Carduus tenuiflorus Curtis Slender Thistle
Fl.Londin.Fasc. 6:Tab. 55 (1789)

Conservation Code: Not threatened
Naturalised Status: Alien to Western Australia
Name Status: Current

Brief Description
Amanda Spooner, Wednesday 23 April 1997

Erect, prickly annual or biennial, herb, to 1 m high. Fl. pink-purple, Sep to Nov. Weed of roadsides, pastures & dry open areas.


Beard’s Provinces: Eremaean Province, South-West Province.

IBRA Regions: Avon Wheatbelt, Coolgardie, Esperance Plains, Jarrah Forest, Mallee, Swan Coastal Plain, Warren.

IBRA Subregions: Avon Wheatbelt P2, Eastern Goldfield, Fitzgerald, Perth, Southern Jarrah Forest, Warren, Western Mallee.

IMCRA Regions: Central West Coast, Leeuwin-Naturaliste.

Local Government Areas (LGAs): Albany, Boyup Brook, Bridgetown-Greenbushes, Busselton, Cranbrook, Gingin, Harvey, Jerramungup, Kalgoorlie-Boulder, Manjimup, Northam, Plantagenet, Ravensthorpe, Rockingham.

Management Notes (for the Swan NRM Region)
Kate Brown and Karen Bettink, Monday 26 August 2019

Alternative Names. Winged Thistle, Shore Thistle, Slenderflowered Thistle.

General Biology. Growth form. Herb. Life form. Annual. Reproduction. Seed. Dispersal. Wind, water, birds. Seedbank persistence. 10+ years.

Notes. Germination of seed is rapid and occurs at high rates. Germinates over a wide range of alternating temperatures up to 6 weeks after autumn rains. Produce two types of seed in each flower head. Those in the center are not dormant and are easily dispersed, while the outer seed can be dormant and have no obvious means of dispersal. Rust fungus as a biological control agent was released in southern Australia in 1993. Hybridisation with Carduus pycnocephalus is common.

Additional information. Origin. Macaronesia, Northern Africa, Europe. Similar exotic species. Carduus pycnocephalus.

Suggested method of management and control. Hand remove isolated plants through spring and early summer. Glyphosate at 50% applied by wick or 0.5% can provide some selective control. Alternatively spot spray Lontrel® 10 ml/ 10 L + wetting agent. Control at rosette stage. An integrated program involving a combination of techniques will be most effective. Read the manufacturers' labels and material safety data sheets before using herbicides. For further information consult the Australian Pesticides and Veterinary Medicines Authority to determine the status of permits for your situation or state.

Management Calendar

Calendar Type Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Comments
Germination         O Y Y            
Active Growth           Y Y Y Y Y      
Flowering                 Y Y Y    
Fruiting                   Y Y Y  
Manual Removal           Y Y Y Y Y      
Herbicide Treatment             Y Y Y        

Legend: Y = Yes, regularly, O = Occasionally, U = Uncertain, referred by others but not confirmed.



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Project information and acknowledgements