Siam weed
Chromolaena odorata
family
Asteraceae
origin
Exotic
declaration
Category 3 Restricted Matter (Biosecurity Act 2014)
Must not be distributed or disposed. This means it must not be released into the environment unless the distribution or disposal is authorised in a regulation or under a permit.
Common names
Armstrong's weed, Baby tea, Bitter bush, Butterfly weed, Christmas bush, Chromolaena, Devil weed, Eupatorium, Jack in the bush, Jack-in-the-bush, Kingweed, Paraffinbush, Paraffinweed, Siam weed, Turpentine weed, Triffid weed.
An upright, sprawling or scrambling shrub with stems produced from a long-lived root-stock. Its slender stems are much-branched, with the side-branches usually being produced in pairs. Its oppositely arranged leaves (5-12 cm long and 3-7 cm wide) are triangular-shaped and have toothed margins. Its small, fluffy, pale pink or pale mauve flower-heads are borne in dense clusters at the tips of the branches. Its black or dark brown seeds (4-5 mm long) are topped with numerous white to brownish hairs (5-6 mm long).https://www.youtube.com/watch?v=lgKWljPTfuE&index=3&list=PLpiCDHV-IjhGh-...
Impact
Impact
Though Siam weed (Chromolaena odorata) is not yet widespread in Australia, and is currently being eradicated, it is regarded as a potentially very serious environmental weed in northern Australia. It is thought that this species would thrive along much of the coastal and sub-coastal districts of northern Western Australia, the Northern Territory and Queensland to north-eastern New South Wales. For this reason it is listed on both the National Environmental Weed Alert List and the Northern Australia Quarantine Strategy list. It is also seen as a major invasive species worldwide, and the Global Invasive Species Database includes it in the top 100 of the world€™s worst invasive alien species.Siam weed (Chromolaena odorata) forms dense stands that prevent the establishment of other species, both due to competition and allelopathic effects, and interferes with natural ecosystem processes in many countries. As well as altering the integrity and diversity of these natural plant communities, it can have an impact on animal populations by replacing food plants and making nesting habitats unsuitable.
Location
Location
Characteristics
Characteristics
Similar Species
Similar Species
Though Siam weed (Chromolaena odorata) is not yet widespread in Australia, and is currently being eradicated, it is regarded as a potentially very serious environmental weed in northern Australia. It is thought that this species would thrive along much of the coastal and sub-coastal districts of northern Western Australia, the Northern Territory and Queensland to north-eastern New South Wales. For this reason it is listed on both the National Environmental Weed Alert List and the Northern Australia Quarantine Strategy list. It is also seen as a major invasive species worldwide, and the Global Invasive Species Database includes it in the top 100 of the world€™s worst invasive alien species.Siam weed (Chromolaena odorata) forms dense stands that prevent the establishment of other species, both due to competition and allelopathic effects, and interferes with natural ecosystem processes in many countries. As well as altering the integrity and diversity of these natural plant communities, it can have an impact on animal populations by replacing food plants and making nesting habitats unsuitable.
