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All Opuntioid cacti species in Australia are introduced and are Weeds of National Significance (WONS) and declared under the Landscape South Australia Act 2019 (except O. ficus-indica). Significant time, money and effort has been spent trying to control infestations using herbicide and physical removal. Despite this, Opuntioid cacti have resisted control efforts and continued to infest rangelands. Since 2016, with the support of Biosecurity Queensland (Queensland Department of Primary Industries), we have developed an Opuntioid cacti biocontrol program. The biocontrol agent we use is cochineal, species of mealybugs that are cactus specific. As a res ult, we have biocontrol agents that assist in controlling 12 of the 15 species of Opuntioid cacti found in the SAAL LB region (Map of infestation locations included). Cochineal has been a game changer in helping to get on top of some of the worst infestations of Opuntioid cacti in our region. Before and after photos in this paper demonstrate how successful this biocontrol has been. Biosecurity Queensland have provided cochineal species, that SAAL LB previously didn't have, that were suited to many species of Opuntioid cacti in our region. In return, we have provided samples of cactus and cochineal that they have used to further develop their Opuntioid cacti biocontrol program through trials and DNA testing of cochineal. The SAAL LB have also been supported by the Port Augusta City Council who agreed to house the SAAL LB Cochineal Nursery on their Australian Arid Lands Botanic Garden site. The Cochineal Nursery was established in 2021 and breeds four species of cochineal, which work on six species of cacti. Cochineal from this facility has been used on infestations on numerous properties in SAAL and other Landscape Boards.