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Hypochaeris radicata L.
Flat Weed

Sp.Pl. 2:811 (1753)
Conservation Code
Not threatened
Naturalised Status
Alien to Western Australia
Name Status

Rosetted annual, herb, 0.08-0.5 m high, leaves rough, bristly; flower heads up to 3 cm across. Fl. yellow, Jan to Dec (mainly in Spring). Common weed of lawns, horticultural areas, roadsides & bushland.

Amanda Spooner, Descriptive Catalogue, 15 May 1997


IBRA Regions
Avon Wheatbelt, Esperance Plains, Jarrah Forest, Mallee, Swan Coastal Plain, Warren.
IBRA Subregions
Fitzgerald, Katanning, Northern Jarrah Forest, Perth, Recherche, Southern Jarrah Forest, Warren, Western Mallee.
IMCRA Regions
Central West Coast, Leeuwin-Naturaliste, WA South Coast.
Local Government Areas (LGAs)
Albany, Armadale, Augusta Margaret River, Boddington, Boyup Brook, Bridgetown-Greenbushes, Bunbury, Busselton, Canning, Cockburn, Cottesloe, Cranbrook, Dandaragan, Esperance, Gnowangerup, Gosnells, Harvey, Kalamunda, Lake Grace, Manjimup, Melville, Mosman Park, Mundaring, Murray, Nannup, Narrogin, Plantagenet, Ravensthorpe, Rockingham, Serpentine-Jarrahdale, South Perth, Stirling, Swan, Wanneroo, Waroona, York.

Management Notes (for the Swan NRM Region)

Alternative Names. Cat's-ear, Spotted Cat's-ear.

General Biology. Growth form. Herb. Life form. Annual. Reproduction. Seed, occasionally vegetatively from perenating buds. Dispersal. Wind. Toxicity. Toxic to horses. Seedbank persistence. Short, days-1 year. Fire response. Resprouts from rootstock after fire.

Notes. May also be biennial or perennial. Common in disturbed areas and can also be found invading natural vegetation in riparian zones, seasonal freshwater wetlands, alpine areas and coastlines. Develops deep roots which are consumed by wild pigs, that are able to dig up large areas in search of the roots. Seedling recruitment is generally higher in Hypochaeris glabra than the similar, often co-occurring species H. radicata. H. radicata generally produces more fruits per plant than H. glabra, but a lower proportion of its flowers set fruit.

Additional information. Origin. Northern Africa, temperate Asia, western Asia, Europe. Similar exotic species. Hypochaeris glabra.

Suggested method of management and control. Wiping rosettes with 30% glyphosate provides effective control. For dense infestations apply Lontrel® 10 ml/10 L + wetting agent. 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       Y Y O              
Active Growth           Y Y Y Y Y Y    
Flowering Y Y Y Y Y Y Y Y Y Y Y Y  
Fruiting O O O O O O O O O Y Y Y  
Herbicide Treatment           Y Y Y Y        

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



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