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Conyza sumatrensis (Retz.) E.Walker

This name is not current. Find out more information on related names.

J.Jap.Bot. 46:72 (1971)
Conservation Code
Not threatened
Naturalised Status
Alien to Western Australia
Name Status
Not Current

Annual, herb, to 2 m high. Fl. white/cream/yellow, Jan to Dec. Gritty loam, sandy clay, grey sand. Sand dunes, ditches, swamps, seasonally-wet sites, road verges.

Amanda Spooner, Descriptive Catalogue, 9 January 2003

Management Notes (for the Swan NRM Region)

Alternative Names. Broadleaf Fleabane, Guernsey Fleabane.

General Biology. Growth form. Herb. Life form. Annual. Reproduction. Seed. Dispersal. Wind. Toxicity. Suspected of poisoning stock, taints milk. Fire response. Killed by fire.

Notes. Widespread weed in warm temperate and subtropical regions, and widespread throughout Australia. Adapted to most soil types and prevalent in disturbed sites. Self-pollinated and cross pollinated. Has high and rapid seed production, high germination rates and dispersal capability. Light stimulates germination. Is a common contaminant of nursery plants. Has recorded herbicide resistance however no glyphosate-resistant Conyza populations have been recorded in Western Australia.

Additional information. Origin. Southern America, North America. Similar exotic species. Conyza bonariensis, C. parva.

Suggested method of management and control. Hand pulling of small and/or isolated infestations after stem elongation prior to seed set is effective on loose soils, but difficult on heavier soils. Mowing is ineffective. Most susceptible to glyphosate at early development of rosette stage. Apply 25 ml/ 10L glyphosate after stem elongation and before flowering in late spring to summer each year when the plants are actively growing. A mixture of 50% glyphosate can be used to wipe the stems of plants. Lontrel® 4 g/ 10 L (200 g/ha) + wetting agent can be spot sprayed for fairly selective control. 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 Y Y Y Y O    
Active Growth O O O O O Y 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 O Y Y  
Manual Removal O O O O O Y Y Y Y Y O O  
Herbicide Treatment           Y Y Y Y Y Y    

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



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