How to kill parkinsonia

Access all the information needed for control of this noxious weed, including weed identification, herbicide application and spray timings.


Parkinsonia description

Parkinsonia identification

  • Parkinsonia emerges as a single thorny stem and matures into a thorny tree with numerous branches and slender drooping green stems.
  • It grows to a height of 6 m and can form dense thickets.
  • Leaves are very thin flattened rachises up to 30 cm long with tiny oblong leaflets in two rows along their length.
  • Sharp thorns 7–12 mm long are present at the leaf nodes.
  • Flowers are predominantly yellow but one petal either has orange spots or is completely orange.
  • There are eight to 12 flowers on each inflorescence.
  • The leathery seed pods are light brown when mature. Pods are 5–11 cm long, each containing two to four seeds.
  • The seed-feeding beetle, Penthobruchus germaini, was released in 1995 and has reduced the amount of viable seed being spread.

Parkinsonia control

How to kill parkinsonia

Parkinsonia is a weed of national significance and is identified as being invasive, having the potential for widespread environmental, social and economical damage. Landowners and land managers at all levels are responsible for actively managing this weed.

The best time to treat for control of parkinsonia is from September through to May as a basal bark or cut stump application with Access, although if conditions allow this treatment can be used year round.

Recommended treatment rate with Access is 1:60 with diesel or Biosafe.

Herbicides for killing parkinsonia

Product#Method of applicationRate*State
Access® Herbicide Basal bark and Cut stump 1:60 with diesel or Biosafe§ All
Access® Herbicide ThinLine basal bark 1:9 with diesel or Biosafe§ All
Grazon® Extra Herbicide Aerial (helicopter only) 3 L/ha + Uptake® Spraying Oil 1 L/ha Qld, NT
Grazon® Extra Herbicide Foliar spray 350 mL/100 L of water + Uptake® Spraying Oil All
Vigilant® II Herbicide Cut stump Apply neat: 3–5 mm layer All

# Note: Preferred product option in bold.  * Consult label for details of growth stage and use, especially where range of rates is given.  § Biosafe – trademark used under licence, Victorian Chemical Co Pty Ltd.

Treatment timing

Timing to kill parkinsonia

Plants should be actively growing and preferably flowering. Field experience has shown that good soil moisture is essential for effective control.

Access® Herbicide
Grazon® Extra Herbicide
Key: Best time to spray/treat Can spray/treat if conditions are suitable Do not spray/treat