Project :

Loan of portable spray unit to control infestations of Paterson’s curse for PHBG landholders wanting to treat plants early to break the germination cycle


Paterson’s curse is a declared weed and is one of the PHBG’s priority pests. Patterson’s curse is a weed of agricultural land as well as roadsides and degraded bushland. It invades farmland and outcompetes pasture species, reducing the productivity of paddocks as well as posing a risk to livestock as it contains pyrrolizidine alkaloids, which are toxic to stock, especially horses.

In the south west agricultural zone, Paterson’s curse has recently returned to the spotlight after seasonal conditions prompted a large germination during 2021. Paterson’s curse can be difficult for landholders to control as it can grow undetected amongst pasture until it flowers, sending up bright purple flower stalks. Once flowering, undertaking control is less successful as Paterson’s curse generally sets seed early. The optimal time to control Paterson’s Curse is when the plant is actively growing, during its ‘rosette’ growth stage.

The early detection and treatment of the plant before flowering is necessary to increase the success of control efforts. Through this project the PHBG will purchase a boom sprayer unit which will only be available to landholders during the optimal treatment time to yield the best possible results. The boom sprayer unit will enable landholders to apply selective herbicides, to paddocks containing Paterson’s Curse, to treat infestations across large areas during it’s rosette growth stage.

The PHBG offers specialty equipment free of charge to landholders within its operational area. The PHBG will undertake a seasonal media campaign to encourage uptake, as well as directly inviting any landholder that receives a ‘Landholder Alert Letter’ for Paterson’s curse to participate in the project.


IN (i.e. what the PHBG will be doing …)

  • Encouraging control of Paterson’s curse to lessen its negative impact on neighbours, assets and the environment

  • Servicing landholders inside PHBG operational area

  • Purchase of spray unit and accessories, to be loaned free of charge

  • Work vehicle and trailer for delivery/pickup of equipment

  • Seasonal media campaign

  • Letters to landholders who have received a letter regarding an infestation on their property

  • On-line equipment booking system

  • Delivery and pickup of equipment, direct to landholder

  • Instructions on use of equipment

  • Maintenance of spray unit and any accessories (unless negligent damage by landholder)

  • Maintenance of vehicle and trailer

  • Record keeping

OUT (i.e. what the PHBG will not be doing …)

  • Achieving complete eradication of Paterson’s curse from the region due to current economic, institutional and technological barriers outside the PHBG’s influence and control

  • Servicing landholders outside the PHBG operational area

  • Herbicide (landholders to supply)

  • Control (landholder to use equipment supplied)

  • Cleaning and triple rinsing equipment (landholder to undertake)


  • Seasonal control report (December of each year for 2022, 2023, 2024)

  • Project summary in annual report (April of each year for 2023, 2024, 2025)

  • End of project report (March 2025)


    • Offer landholders timely access to a portable spray unit to control their Paterson’s curse when plants are at a rosette growth stage (i.e. before flowering).

    • Guide landholders on the best use of the portable spray unit for the effective control of Paterson’s curse.

    • Increase the number of landholders undertaking Paterson’s curse control using PHBG resources and equipment.


  • February - Purchase of equipment (initially one unit, to be reviewed after each control season)

  • April - Confirmed date of launch event

  • April - Advertising Program and Event

  • May - Host Event

  • May - Online booking system set up

  • May - September - Delivery of equipment, landholder engagement

  • October - Report and media release


  • Number of landholders who self-nominate into the project.

  • Number of landholders who are invited into the project (with a reported & validated infestation).

  • Number of landholders who participate in the project.

  • Number of landholders who provide feedback.

  • PHBG workflows completed to a satisfactory level (e.g. Job Safety Analysis, Vehicle Safety Checklist, Equipment Maintenance Checklist, Landholder Handover Checklist)

  • Landholder satisfaction with equipment and PHBG support.

  • Number of reports completed on-time.