The loss of markets, key chemicals and consumer confidence are some of the risks the cropping sector faces if it doesn't tackle the growing problem of spray drift.
That was the message from a range of speakers at an open and honest spray forum hosted by Grain Producers SA at Freeling on Thursday.
GPSA grower chair John Gladigau said chemical stewardship had been among the most discussed topics during his three years on the board.
He said the grower group was looking at all options to stop spray drift, saying it was not only impacting farmers but communities as well.
"We have a problem and that problem is we're seeing an unacceptable level of off-target chemical damage across our state," Mr Gladigau said.
"Despite our best efforts, the damage is increasing not diminishing and we need to work out why and we need to make changes.
"We need to do it before others put unacceptable changes on us."
Among the efforts being made to cut through to farmers are the organisation's spray pledge, 'don't spray your dollars away' campaign and a recently-commissioned project to analyse farmer attitudes to the issue and review industry best practice.
One event that brought the issue into focus last year was a PIRSA investigation into dozens of reports of off-target spray damage on roadsides and in gardens on the Yorke Peninsula.
No penalties eventuated, but an auditing program was conducted on nearby farmers and more surveillance of spraying activities conducted during inversion conditions.
IT'S NOT JUST A FEW COWBOYS: O'BRIEN
Spray drift expert Mary O'Brien, O'Brien Rural Services, Dalby, Qld, told the forum that lack of regulatory action was one blockage to spraying practice change and that was often caused by industry.
Contrary to some opinions, Ms O'Brien said spray drift was often a cumulative effect and not just the result of a few bad operators.
"I used to think it was just a few cowboys, but I don't believe that anymore," she said.
"Even people trying to do a good job with a good nozzle, setup, boom height and speed can still add to the problem.
"I call that community drift, the little bit coming from everybody. If you were the only person spraying there'd be no dramas, but there's 20 other people in the district spraying and everybody adds those 1pc driftable fines."
Misunderstanding or lack of knowledge about wind conditions is often the cause of those driftable fine chemical droplets travelling tens of kilometres and leading to off-target damage, Ms O'Brien believes.
During inversion conditions, which often last from late afternoon to the following morning, Ms O'Brien said buffer zones "go out the window" and spray can travel tens of kilometres.
During those times wind moves parallel to ground and there is no turbulent air movement to drag chemical back to the ground.
She said a common myth is that inversions are unlikely to be in place if the wind speed is between 3 and 15 kilometres an hour
"It's not about the speed of the wind, it's about how it moves," Ms O'Brien said.
"Under inversion conditions, wind will move like water along the landscape. It's very unpredictable and it's hard to know where those fine droplets will end up."
She advised farmers pay attention to how air is moving before spraying, and adopt responsible boom heights, droplet sizes and sprayer speeds.
"Everything that makes your drift worse, reduces your efficacy."
Typical signs of an inversion include fog, mist or dust hanging in the air, sounds becoming clearer, and frost or dew.
LOSS OF SOCIAL LICENCE A BIG RISK: PRESTON
The loss of key chemicals like 2,4-D and even the loss of social licence, meaning growers could no longer apply crop protection products at all, are major risks the industry is running according to University of Adelaide weed management professor Chris Preston.
"I'm out talking to the urban community and they're becoming increasingly skeptical about pesticide use in agriculture and that's a problem," he said.
Very rare instances of miniscule amounts of ag chemical found in food should be the least of the public's concerns, Mr Preston said, and he could defend the industry against that, but there was no defending against spray drift.
"Spray drift is now starting to be recognised as a concern by the community," he said.
"One of the things we've really got to worry about moving forward is how do we keep the community with us and I think we can only keep the community with us by doing the right thing."
While it is often the first message delivered when talking about any agricultural chemical, all forum speakers said label instructions had to be followed and a lackadaisical attitude towards following those had to come to an end.
"If farmers had actually followed exactly what was on the label, we would have limited incidences of off-target damage from Overwatch," Prof Preston said.
"All the information a farmer needs to get it right is on the label."
