A species of minuscule spiders will be released in the ACT this month in an effort to kill control environment weeds, according to ACT Parks and Conservation Service.Gorse spider mites feed exclusively on Gorse, a plant native to western Europe which is now listed as a weed of national significance in Australia due to its invasive nature. The spiders, which are almost too tiny to see, have piercing and sucking mouthparts that pierce individual cell walls of gorse foliage and extract the cell contents. Extensive feeding pressure can kill shoots and reduce plant growth.
Steve Taylor of ACT Parks and Conservation Service says the mites have been introduced to a site at Bruce, where it is hoped they will eat through a significant amount of Gorse and establish a colony population so they can be used in other sites.
“Gorse weeds invade bushland, threatening the survival of native plant species, and provides shelter for other pests, such as rabbits and foxes. In the ACT, Gorse infestations are localised and cover small areas, as it has been controlled with a rigorous herbicide program,” Steve says.
“While a lot of the work in controlling this pest species is done with selective herbicides and mechanical removal, the mite is used to further weaken the plant. There are a number of sites across the ACT where mites have been introduced to control weeds, including Scotch Broom mite, which was released earlier this year in Williamsdale. The plan is to establish about half a dozen other sites for Gorse spider mite in the ACT.
“Importantly the mites do not feed on any other plants. Bio-control agents, such as Gorse spider mites, are only released from quarantine after rigorous testing over a number of years to ensure they do not affect other species. It was provided to the ACT free-of-charge as part of a partnership with the CSIRO and Victorian Department of Environment and Primary Industries.”
For more information on weed control work in the ACT visit www.tams.act.gov.au or call Canberra Connect on 13 22 81.