Parkinsonia aculeata (parkinsonia) is a Weed of National Significance that has an impact across the rangelands of Northern Australia. Parkinsonia was introduced in the Australia as an ornamental species and for its potential value as a hedging and fodder plant. It has since spread to occupy over 8000 km2 of the rangelands of northern Australia, and is capable of significantly greater spread based on the suitability of the climate of the northern Australia. Parkinsonia forms dense thickets in floodplains and grasslands, and along water courses and bore drains. It has negative impacts on the pastoral industry and rangeland production systems through limiting pasture growth, restricting stock access to water and impeding mustering. It also has impacts on the environment through providing refuges for feral animals like pigs, increasing evapotranspiration, contributing to soil erosion, and impacting wildlife habitat. At present widespread prickle bushes like parkinsonia can have control costs between $2‐$300/ha/y depending on the density of infestations. Cost‐effective management methods are therefore needed for this weed; biological control is one such method.

The initial CSIRO’s work on parkinsonia biological control was funded by contributions from Meat & Livestock Australia and the Cattle Industry Funding Scheme of the Department of Agriculture and Food Western Australia. A subsequent collaborative project between CSIRO and QDAF from 2016-18 was supported by funding from the Australian Government’s Department of Agriculture and Water Resources as part of its Rural R&D for Profit Programme. Current funding for integrated management and development of additional agents is from Meat & Livestock Australia 2020-23.