Triffid weed or Paraffin bush - Chromolaena
This invasive alien species is
present in the Mount Moreland Conservation area
Chromolaena odorata commonly known as Chromolaena, Paraffin bush or triffid weed is a
flowering shrub in the daisy family, Asteraceae it is native to North America, from Florida and Texas to Mexico and the Caribbean.
Chromolaena odorata is a scrambling, sparsely hairy shrub growing up to four meters or higher
often forming dense thickets. The stems are opposite with wide spreading-branches they have light green,
ovate to tri-angular leaves, with three conspicuous veins originating in the base of the leaf. The plant
exudes a strong smell of paraffin when crushed. It produces masses of white daisy like flowers during the
winter months when it is most easily recognised and controlled.
Chromolaena is one of the world’s worst weeds.
Chromolaena odorata is recognised as one of the world’s worst weeds which is very widely
distributed and is still expanding its range due to its very effective long-distance wind dispersal of seed.
It is viewed as a major environmental weed. Chromolaena odorata has been reported to be the most problematic
invasive species within protected rainforests in Africa. In South Africa it is regarded as a dangerous
invader. Chromolaena odorata germinates readily, grows rapidly and produces vast quantities of wind dispersed
seeds it is highly competitive.
The control of Chromolaena is very easily achieved but it is an ongoing process as new seeds
continue to blow in from distant infestations. The most effective means of eradication and control for small
infestations is to remove the entire plant including the roots mechanically such
as by hand weeding or digging and uprooting using a mattock or spade. For larger infestations the best method
is to use machinery such as brush cutters or heavy duty mowers
to remove and mulch the top growth of the plant followed as soon as is possible by an application
of a herbicide containing glyphosate or triclopyr mixed at the
rate of 1% with water which is applied to the cut stump.
For small infestations spot spraying with a herbicide containing glyphosate or triclopyr mixed
at the rate of 1% with water is also very effective but care must be taken not to damage no target plants.
Regular follow up to check for new seedlings and re-growth is important in the control of
Paraffin weed. The most important rule in the control of Chromolaena odorata is to not allow any plants occurring on your property to ever be given the
opportunity to seed. The removal of any plants that have been overlooked during the year is easily achieved
during the winter months when the plants are in flower because at this time they are very easily located and