A new wave of hungry caterpillars are set to be released as biological control agents for the pest weed Parkinsonia across Queensland.
The program, as a CSIRO/Department of Agricultures and Fisheries joint project aims to mass-rear and release leaf-eating ‘UU caterpillars’ into Parkinsonia infestations within Queensland where it launched in 2013, and the Northern Territory and Western Australia where it commenced July this year.
“Our goal is for establishment of UU to occur at all the initial release sites, and so far we have detected establishment at over half, however there are still more to be monitored which means that number could potentially increase,” a spokesperson of the Department commented.
“The UU larvae do this by eating the leaflets and damaging the leaf parts causing defoliation…this also leaves the plant susceptible to additional attacks from other diseases such as dieback.”
According to the DAF, at least 18 new sites are set to be added to the program and 10,000 pupae will be released over eighteen months.
“The overarching aim of the program is to decrease the reproductive capabilities and spread of Parkinsonia.”
Efforts of researchers at the DAF’s Tropical Weed Research centre have been praised by Minister for Agriculture and Fisheries Leanne Donaldson.
“It’s fascinating to see the results of research into the use of insects as weed control agents,” the Minister said.
Once established, the populations are self-sustaining and able to spread without assistance, making them long-term management tools to aid landholders in tackling invasive weeds on their properties with no direst costs.
“The good news for the community is that UUs are now available free to landholders, councils, national parks and Landcare groups in Queensland to use on large patches of Parkinsonia.”
The DAF states, however, that the use of UU is not without limitations, as although they control the spread of the weed, they are still unable to kill it.
“They are able to help manage the weed but on their own cannot eradicate populations,” the spokesperson said.
“That is why for success to occur UU needs to be used in conjunction with other control methods…therefore, those looking for immediate results to control weeds won’t find it by using biological control agents alone.”
Most mass-rearing programs run for three years however the DAF has gained industry support for additional funding to extend the UU project.
Funding for the program has been granted under the Meat and Livestock Australia and the Federal Department of Agriculture and Water Resources, Rural Research and Development for Profit funding.