A single application of Exirel® insecticide produced long-term control for canola growers last season, at Geraldton, in the mid-west region of Western Australia.
Darcy McDonald, of Great Northern Rural Services at Geraldton, said the region typically had shorter seasons and would often be first in the state to be inundated with bugs. He said the majority of farms were also quite large, so scouting across paddocks and recommending products for the situation could be challenging.
“Last year we had a late break with the first rains at the start of June. We were sweeping the earliest crops and weren’t finding many bugs, and it seemed good.”“Then at the start of September we had some easterly winds. The first two or three paddocks we checked after a week of easterly winds showed massive amounts of Heliothis, and then we started to find Diamondback Moth (DBM).”
“I kept sweeping and just finding more and more. We were getting 200 Heliothis and over 200 DBM in a sweep. I’d been there the previous week, and the pressure just went bang so quickly.”
Mr McDonald said he sat down with the team at Great Northern Rural Services to determine the best options to address the situation. SP or OP insecticides were not considered, with concerns about insect resistance which left just two viable products to tackle the problem. He said they looked at both options, taking into consideration the expected length of control and the benefit of keeping beneficial insects in the crop.
“Exirel® seemed the most logical, smartest and cost-effective option to go in first. “We didn’t have enough on the shelf to do all the farms with Exirel® but the growers that used it were really happy with the product.”
“Most of the applications were made at about 30 per cent to 50 per cent flowering and it got us well and truly to the end of the season. We got at least four to five weeks residual benefit, and I didn't see another bug in the paddock after application.”
“Whether it’s keeping the beneficials in the paddock or it’s the translaminar movement of the product, it worked really well.”
Last season was challenging for canola, however, crops still had projected yields of 1.8 to 2.3 tonnes per hectare and were well worth trying to protect from the onslaught of pests.
“Growers could use an economical product like Exirel® to protect a crop and not worry about coming back. It was a big relief for a lot of growers that were walking through their paddocks with snake sized grubs hanging off pods and coming back at harvest and most of their canola, if not all, was still there.”
The enthusiasm for Exirel® carried through to 2025, with growers keen to utilise it again.
“A couple of our growers at the start of this year bought Exirel® with their pre-emergent order. So that shows you how confident they were in using the product and how well it worked”.
“I tried to advise them not to buy it because I thought we might not get DBM but they said this is gold so I'm going to get it on farm.”
Exirel® was applied by boom spray and also out of a plane and Mr McDonald said, even at an aerial application of 30 litres per hectare, they had excellent results.
He said there weren’t too many aphids detected last season, but he was considering using a high-quality oil, such as Parachute®, in conjunction with Exirel® for that pest.
“We're not excited to see aphids, but I'm excited to see if we can control the aphids with Exirel® and a bit of oil,” he said.