'Think twice' about chemical

National Working Party on Grain Protection chair Gerard McMullen said it was his job to "look after market access in relation to chemicals being used on crops" and that carbendazim, which is often used by farmers for snail control, was "under scrutiny" in international markets.

"[The International standard for chemical residues] Codex late last year recommended the withdrawal of all carbendazim MRLs," he said.

"The regulator here in Australia, the AVPMA, reviewed it in 2014, while the European Union have said that they're going to drop their MRLs for carbendazim on all commodities early next year, so any residue detection will be a violation.

"A lot of Middle Eastern markets, South East Asian markets, where we send our red lentils, also don't have a carbendazim MRLs so any detection is a violation.

"So if you're thinking of using carbendazim in the future, I'd think twice."

Mr McMullen was a guest speaker on a panel with GRDC pests manager Leigh Nelson and Grower Supplies agronomist Jake Rademacher at the grains research conference.

The group discussed snail management, including challenges, recent research and carbendazim usage.

"One of the challenges surrounding growing crops and using chemicals is the ongoing use of the word 'sustainability', which is basically about minimising chemical usage," he said.

Mr McMullen said Australia had a fantastic reputation for complying with market requirements, but residues, like carbendazim, were still being picked up on some crop commodities.

"So while we're good, there's always room for improvement," he said.

"Technologies in picking up chemical residues are always improving, down to the parts per billion, so following label directions is vital.

"If grain deliveries don't have the appropriate MRLs that means it's a misuse, and if it's against label directions, it's against regulations.

"If we don't comply, that puts greater scrutiny on us in terms of the markets wanting to push back and getting more involved in what growers are doing on-farm.

"So it is important we comply with their requirements."

Mr Rademacher said the snail burden wasn't getting any better.

"With the long growing season in 2022, snails got out of hand quickly," he said.

"Then with the extended harvest into early 2023, it limited summer control methods of cabling or rolling, where we can get up to 60 per cent control of snails.

"It also meant summer baiting strategies weren't on time either. Thankfully, there's some real exciting research being undertaken."

RELATED READING: Farmers must advocate in sustainability space: Barr

Ms Nelson highlighted some research projects that looked into pinpointing the timing of snail movement to predict when to bait, making cabling "more of an efficacious practice" and the use of parasitic flies on troublesome conical snails.

"One project is looking at enhancing biocontrol, as it was observed that there was up to 58pc parasitism of conical snails where flies had established well," she said.

"But it was noted that the flies need floristic resources to get protein to complete their lifestyle.

"So this program looks at revegetating alongside cropping areas and at receival sites, to then measure the effect that revegetation has on the parasitism rates of conical snails in those areas."