Heart-leaf poison bush

Native to tropical Australia, heart-leaf poison bush is a woody perennial shrub. It is found from Western Australia's Hamersley Range through the Northern Territory to Cape York Peninsula and Queensland's central highlands.

Heart-leaf poison bush is poisonous to stock, requiring pastures with this plant to be fenced. It is known as desert poison bush in central Australia and wallflower poison bush in Western Australia.

Heart-leaf poison bush is not a prohibited or restricted invasive plant under the Biosecurity Act 2014.

Scientific name

Gastrolobium grandiflorum

Other names

  • Desert poison bush, wallflower poison bush

Description

  • Native woody perennial shrub up to 1–2m tall.
  • Stems are woody, grow from lignotuber or bulb below ground level.
  • Leaves are greyish green, thick, stiff, usually opposite, 2.5–6.4cm long, 1–2.7cm wide.
  • Leaves have prominent yellow veins, are tapered at base.
  • Flowers are dark red to purplish, pea-shaped, 2–2.5cm long.
  • Pods are small, yellowish-brown, hairy, pointed at tip, usually contain 1–2 seeds about size of sweet-pea.

Habitat

  • Occurs sporadically, mainly in creamy to red sandy clay soils in eucalypt woodland.

Distribution

  • Central highlands.
  • Cape York Peninsula.

Life cycle

  • Germinates during wet season.
  • Flowers December–April.

Affected animals

  • grazing stock

Impacts

Environmental

  • Poisonous to grazing animals.
  • Contains high levels of monofluoroacetic acid (1080 poison).

How it is spread

  • Seeds spread by flowing water, animals, machinery and vehicles.

Control

Physical control

  • Dig up small infestations by roots, allow to dry out, then burn.

Herbicide control

  • Spraying the plant with diesel will stop stock from feeding on it. This treatment can kill the plant but it will regrow in some circumstances.
  • Herbicides that can be used for control are Tordon TCH, Garlon 600 and Velpar. Although these herbicides are not registered for control of heart-leaf poison bush, they are registered for use in pasture situations.
  • Plants may be sprayed at any time of year, but results are usually best when plants are actively growing and not under stress. A single treatment will destroy most bushes but follow-up in subsequent years is necessary to destroy seedlings.
Large infestations
  • Fence off infested areas to minimise stock loss.
  • Herbicide control can be used, as above.

Biological control

  • No known biological control agents.

Legal requirements

  • Heart-leaf poison bush is not a prohibited or restricted invasive plant under the Biosecurity Act 2014. However, by law, everyone has a general biosecurity obligation (GBO) to take reasonable and practical steps to minimise the risks associated with invasive plants under their control.
  • Local governments must have a biosecurity plan that covers invasive plants in their area. This plan may include actions to be taken on Heart-leaf poison bush. Some of these actions may be required under local laws. Contact your local government for more information.