The most successful agents in Australian history, namely the cactoblastis moth, cochineal insect and a mealy bug, continue to keep cacti under control; however, not all biological agents attack all cacti.
How to kill Cacti
Different application techniques may be used to treat different cacti. Access™ used at 1 L/60 L of diesel applied as an overall spray gives effective control of most cacti. This is the best treatment for quick and economical control of small (seedling) cacti.
Using Grazon™ Extra at 500 mL/100 L of water as a foliar spray will give slow burn down and regrowth may occur, so follow-up application may be necessary. Tordon™ RegrowthMaster at 2.5 L/100 L of water will give effective control of harrisia cactus.
Herbicides for killing Cacti
* Consult label for details of growth stage and use, especially where range of rates is given.