(Senecio madagascariensis)
Note: this is a different species to
fireweed (Senecio linearifolius), a common and widespread native shrub in Tasmania.
Image above: Fireweed is a heavily branched
daisy-like plant, © Q'ld Gov’t.
Legal status of fireweed (Senecio madagascariensis) in Tasmania
- Fireweed is a
declared weed under the
Tasmanian Biosecurity Act 2019 and associated Regulations. The importation, sale and distribution of fireweed are prohibited in Tasmania.
- Fireweed is also a
Weed of National Significance (WONS).
- The legal responsibilities of landholders and other stakeholders in dealing with fireweed are laid out in the Statutory Weed Management Plan for Fireweed.
- Fireweed does not occur in Tasmania.
What does fireweed look like?
- Fireweed is a member of the daisy or Asteraceae family, which shares the characteristic daisy-like flower, and is very similar in appearance to several native Senecio species.
- Growing from 10-60 cm high with conspicuous bright yellow flowers 1-2 cm in diameter, fireweed has a variable growth habit and leaf structure, but is generally a much branched, annual or short-lived perennial herbaceous plant.
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Image above left: Fireweed seedling showing serrated leaf margins, © Q'ld Gov’t.
Image above right: Fireweed seeds are readily spread by wind, © Harry Rose (Wikimedia).
Impacts of fireweed
- Fireweed is a well-adapted colonising species often found in overgrazed and poor pastures, open forests, urban areas, roadsides and neglected sites. Heavy infestations can develop on cultivated and disturbed land.
- Fireweed seeds prolifically and grows to maturity quickly; germination to flowering and seed set can occur between six to ten weeks. Fireweed can spread very quickly as seeds are small and can germinate immediately after dispersal. This rapid development may enable up to four distinct generations of fireweed per growing season and makes long-term eradication very difficult.
- Seedlings are rapidly recruited from an established seed bank in response to a range of environmental disturbances. Most seed will fall within five metres of the parent plant. However, the light fluffy seeds are easily caught by the wind and some seed will be spread greater distances by wind and updrafts.
- Further dispersal is likely to be the result of unintentional spread by human activity, including livestock, native or pest animals, clothing, vehicles and machinery, contaminated hay, silage, and grain products.
- Fireweed contains pyrrolizidine alkaloids, which are toxic to livestock and can cause liver damage. Horses and cattle are most affected, while goats and sheep seem better able to tolerate the toxin.
Where does fireweed occur?
- The genus Senecio is widespread throughout the world, with many Senecio species native to Australia. Fireweed itself is native to Madagascar and southeast South Africa. It is a problem weed in Australia, Hawaii, Japan and parts of South America. Recent molecular studies have shown Australian fireweed is most closely related to populations in the Kwa-Zulu Natal province of South Africa.
- Fireweed was first collected in the lower Hunter Valley of New South Wales in 1918. It is thought to have spread to the NSW north coast in crop seed by about 1940. Since then fireweed has established in temperate and subtropical pastures of coastal NSW, southern Queensland, and Victoria (East Gippsland).
- For further information or help in identifying fireweed, refer to the Commonwealth of Australia website,
Weeds of National Significance - Fireweed. If you are still in doubt about the weed you are dealing with, contact Biosecurity Tasmania on 03 6165 3777 for help.
What you need to do
- If you locate fireweed anywhere in Tasmania, or if you find a plant that you think could be fireweed, immediately contact Biosecurity Tasmania on 03 6165 3777 to report this weed.
See also