GETTING THE DRIFT ON CHEMICAL SPRAYS: Mallee Sustainable Farming held a meeting in Irymple this week to discuss the issue of chemical spray-drift which has the potential to be a costly problem for farmers. Pictured is Agriculture Victoria Statewide Specialist for Chemicals, Steven Field, and MSF CEO, David Bone. Photo: PAUL MENSCH

By JOHN DOOLEY

THE problem of spray-drift was a hot topic of conversation at a meeting facilitated by Mallee Sustainable Farming (MSF) yesterday at the Department of Agriculture’s offices in Irymple.

The meeting was attended by a large cross-section of stakeholders from the agricultural sector, including representatives from the grain-growing industry, table grapes, dried fruits, citrus and almonds, government departments including the Victorian Department of Primary Industry, Biosecurity South Australia, the Mallee Catchment Management Authority and the Grains Research and Development Corporation and Cotton Australia.

MSF CEO, David Bone, said the meeting’s format was an “open-facilitated” discussion which saw input from all stakeholders who put the issues on the table for debate.

“The main thrust of the meeting was to get a better understanding about the problem of spray-drift in the Mallee,” he said. “We need to understand how widespread the issue is, who is being affected, which industry sectors are most at risk, and who is monitoring the spray-drift incidents.”

Mr Bone said that following those discussions the strategies that ensued from the meeting will be implemented to help alleviate the problem.

“The conversation also canvassed how each sector can work together and what the best way to implement an effective, collaborative approach to addressing the problem,” he said.

Spray-drift is considered a big hazard to the agricultural industry, and has been the subject of some massive damage payouts awarded by the courts against owners of properties who have allowed chemical spray to drift onto a neighbouring property, poisoning crops.

In one case, a Mallee farmer was ordered to pay his neighbour more than $7million after poisoning 8000 grape vines with toxic spray-drift.

There are two types of spray drift. One is ‘physical drift’, where the chemical spray simply drifts across to another property, carried by the wind, and the other is known as ‘inversion drift’, which is a more difficult problem to deal with.

“Inversion drift takes place when the chemical particles are lifted into the air-stream as the result of surface temperature inversions, and can be carried up to 150kms away, and it then becomes very difficult to determine what the source of the spray-drift was,” Mr Bone said.

“The good news is that the vast majority of farmers are doing the right thing, they respect their neighbours and vice-versa.

“There are measures that farmers can take to minimise the risk of spray-drift and they include using the right spray nozzle to ensure the droplet size is always above 100 microns, lowering the height of the spray-boom, and most importantly regularly checking the weather conditions while they are conducting spraying.”

December is the time Mallee grain producers implement their summer weed control, which coincides with the most critical time for the development of grapes on the vines. It’s during this time that ‘off-target’ spray-drift creates a potential for damage to be inflicted on horticultural crops.

Both industries are significant contributors to the local economy and need to coexist in the region, and that’s why the meeting held yesterday was seen as vitally important in finding ways for the cross-section of industries to operate side-by-side.

Speaking last year, spray drift expert Bill Gordon said he had been urging farmers to improve their spraying behaviours for many years, but the change has only been gradual.

“The odd large legal case that we have seen recently I think will send a wake-up-call to a lot of growers,” he said.

At the same time MSF chairman, and Ouyen grain grower, Ian Hastings, said better technology was helping farmers reduce spray-drift.

“We’ve now got nozzles which are air-inducted and have far less likelihood of allowing drift,” he said. “However we’ve also recognised the dangers of the alternate crops growing in our region, and the areas you have to remain away from with any herbicide 2,4-D product.”

Agriculture Victoria Statewide Specialist for Chemicals, Steven Field, who attended the meeting, said issues relating to spray-drift are generally weather-related.

“Spraying is weather-dependent, and farmers will go out and spray herbicides when there’s been rain over the summer in an effort to retain the moisture in the ground,” he said.

Mr Field said the main issues tended to be with phenoxy herbicides (2,4D), which are commonly used by grain growers to control summer weeds.

“The issue arises when spray moves off target causing damage to horticultural crops, but equally there is the potential for horticulturalists to cause spray-drift onto the grain crops,” he said.

“There’s more research to do to really understand how this is occurring, and today’s session will hopefully further identify some of the main reasons behind the problem, some of which relate to farming practices.

“There’s no doubt when we are looking at herbicides like 2,4D there are specific instructions on the labels of those products that should be followed to minimise the risk of spray drift.

“Chemical users are required to achieve a very coarse droplet size and not to spray when surface temperature inversions are present, given that almost every night there is a surface temperature inversion present, we would be discouraging farmers from spraying in those conditions.”