BY PHIL SOMERVILLE
“The cochineal insect is proving to be specific to Hudson pear and is having a marked impact on its spread,” continues Andrew. “Biosecurity officers have also reported a significant decrease in the use of herbicides over the last couple of years, due to the impact that the biocontrol agent is having. “NSW DPI has provided face-to-face training to over 50 landholders, and new participants are constantly getting involved. This has included how to safely collect Hudson pear cladodes, how to swap and transport the cochineal biocontrol agent, and how to release it. We are always on the lookout for more participants.” The company InFarm has been contracted to develop an Artificial Intelligence (AI) approach for detecting Hudson pear from aerial imagery, which is being used to assess spread and the impact of the agent over large areas and across inaccessible terrain. “Once this high-resolution imagery dataset is captured, it will be run through a supercomputer with a custom algorithm to determine exactly where Hudson pear is located in a 200,000-hectare area,” explains Andrew. “This data will feed into the Hudson pear management plan.” The Hudson pear biocontrol project is funded through the Federal Government’s Department of Agriculture, Water and the Environment Rural Research and Development for Profit (Round 4) program, and is managed by AgriFutures Australia. l
The not-so-nice Hudson pear
dispersal means it has also spread to an estimated 20 additional sites where it has not been released.” Hudson pear was first detected in Australia in the Lightning Ridge area during the late 1960s. It is believed to have spread from a cactus nursery at Grawin and has since infested around 100,000 hectares of land in the North West. According to mapping by NSW Local Land Services, the Hudson pear cactus has the potential to invade up to 112 million hectares of arid land across Australia.
THUMB S UP
Community members examining a Hudson pear killed by the cochineal Dactylopius tomentosus (lineage californica var. parkeri) at a release site in Grawin, NSW. Photo: NSW DPI.
The Hudson pear is named after a resident of the Lightning Ridge area, Mr Hudson, who first brought the problem to the attention of the then Prickly Pear Destruction Commission. Hudson pear has particularly vicious spines which are capable of penetrating footwear and even vehicle tyres. The spines are encased in a detachable sheath, which can remain embedded in a wound even after the body of the spine is removed. The spines can cause serious injury to humans, livestock and working animals such as horses and dogs, and may present a severe impediment to mustering operations. Hudson pear also poses a threat to native fauna and has been known to cause the death of native animals including koalas. Infestations of Hudson pear cactus can also displace native flora and may have an impact on biodiversity.
JAN - FEB 2022
THE FARMER
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