Weevil Control Wasp Must Head West
NEW ZEALAND - Increasing clover root weevil populations are being seen on the West Coast, but the AgResearch-introduced biocontrol is hot on its tail.AgResearch entomologists Dr Scott Hardwick and Mark McNeill, based at the Lincoln Campus in Canterbury, have been tracking the spread of clover root weevil (CRW) in the South Island, so that they know if and where to release the Irish wasp, a very effective biocontrol agent for this serious pest of white clover.
?Sampling last winter and early spring for the DairyNZ-funded biocontrol project has revealed that the weevil is now present through much of the northern parts of the West Coast.
AgResearch is now asking southern West Coast farmers who suspect they may have the weevil to get in touch, so they can be sure the wasp keeps apace of the problem.
In 2006, AgResearch scientists, supported by DairyNZ, Beef + Lamb NZ and AGMARDT, made a breakthrough in CRW control by releasing a potential biocontrol agent, a tiny parasitic wasp from Ireland.
The first trial releases were made in Waikato, Hawke’s Bay and Manawatu, and within just 18 months the wasps’ performance had exceeded the expectations of even the most optimistic scientists.
Dr Hardwick says they found potentially damaging populations of the weevil from Greymouth north through to Karamea but in spite of extensive sampling south of Greymouth, they only discovered a single infested site in Waitahi.
“The good news is that clover root weevil has brought its own destruction with it. The Irish wasp has been confirmed at many localities including Little Wanganui, the outskirts of Westport, Cronadun, and Greymouth,” he says.
TheCattleSite News Desk