Limnocharis

Limnocharis is a declared Class C weed.

Other names for this plant are yellow burrhead or Limnocharis flava.

If you think you may have seen limnocharis, or have this weed on your property, do not attempt to control it. Contact the Weed Management Branch immediately for assistance.

Identification

You should use this as a guide. There may be other plants or weeds that look similar.

If you are unsure, contact the Weed Management Branch.

Habit

These features describe the habit of this plant:

  • erect, perenial, anchored, aquatic plant
  • grows to 20 to 100cm tall.

Limnocharis - habit 

Stems and branches

These features can identify the stems and branches:

  • distinctive, triangular leaf and flower stalks
  • succulent
  • rooted in the mud.

Limnocharis - stems and branches 

Leaves

These features can identify the leaves:

  • petioles 5 to 75cm long
  • leaf blades 5 to 30cm long and 4 to 25cm wide.

Limnocharis - leaves

Flowers

These features can identify the flowers:

  • ‘octopus’ like groups of five to 15 flowers
  • individual flowers are small with three yellow lobes
  • cup shaped
  • at the end of long stems
  • held up while flowering but bend and droop back into the mud or water after fruiting.

Limnocharis - flower

Fruit and seeds

These features can identify the fruit and seeds:

  • spherical, compound fruit
  • 1.5 to 2cm diameter
  • contain many dark brown horseshoe shaped seeds
  • 1 to 1.5mm long.

Impact

Limnocharisposes a significant risk if it was to become established in NT waterways.

Limnocharis can have all of the following impacts:

  • replace native plants
  • form dense choking infestations.

Habitat and distribution

The native range of limnocharis extends from Mexico to Bolivia, Paraguay and northern Argentina. From its native range, limnocharis has moved into parts of south-east Asia, Africa and the south Pacific.

It is thought that limnocharis may have been spread inadvertently through contaminated imports of rice and intentionally for ornamental purposes. Limnocharis has now entered northern Australia. 

There are no known infestations of limnocharis in the NT, but it has occurred in ornamental ponds several times in the past and is known in several locations in Queensland.

Limnocharis presents a serious agricultural and biodiversity threat to northern Australia and has the potential to invade wetlands, rivers and dams displacing native aquatic plants and animals. 

Specifically limnocharis colonises shallow freshwater wetlands and margins of deeper waterways.

There are no known occurrences of Limnocharis in the Northern Territory. 

Infestations in northern Australia have generally been limited to ornamental ponds, however there are three known infestations in natural waterways in Queensland. The level of threat posed by Limnocharis has triggered a call for national eradication.

Control

If you think you may have seen limnocharis, or have this weed on your property, do not attempt to control it. Contact the Weed Management Branch immediately for assistance.

Last updated: 27 June 2017