Grass-roots community organisation that aims to improve the natural condition of the Derwent catchment



The following page is a brief summary of information available on the DPIPWE website regarding Cumbungi control. For more information view here

Non-chemical control

Physical removal

  • Small plants can be removed by hand-pulling or with a spade. Make sure all pieces of the roots and rhizomes are removed, otherwise the plant can quickly regrow.
  • Larger infestations can be removed by mechanical excavation. Care must be taken to avoid damage to the structure of the waterway.
  • Excavated material should be dumped well away from the water at a site where it can dry out and kill all plants.
  • Repeatedly cutting all leaves at 50-150 mm below the water surface can be used to control small infestations. First cut when the flowering period is well advanced (around January), with follow up cuts at 4 to 6 weekly intervals.
  • Most plants will die in the first year using this cutting method. A second year of treatment should finish off any plants which survive the first treatment.


  • If low water levels permit, an alternative to excavation may be to cultivate the site in autumn.
  • This brings root and rhizome material to the surface to dry out.
  • This method gives good control over small infestations, and can reduce the size of large infestations to manageable levels.

Chemical control

Use herbicides in accordance with label. Refer to APVMA permit PER13160 where herbicide is to be used in non-cropping and bushland areas

Application method

1. Foliar spraying

  • Stage of growth - Actively growing
  • Suggested herbicide -  Roundup®Biactive™.

Derwent Catchment Project

PO Box 22 Hamilton TAS 7140  |  Phone (03) 6286 3211  |