Spray drift WAND tool requires change from cotton growers

Stretching from Emerald in QLD to the Victorian border, WAND towers identify, in real time, whether a hazardous inversion is present, helping operators to inform their decision to spray in accordance with label requirements - and in a way that minimises off-target impacts on neighbouring crops.

Over 2000 cotton and grain growers and spray operators have already signed on, keen to explore how they can claw back more control over the complex decision of when not - or, more critically, when - to spray.

Until now, working out if an inversion is present has come down to guesswork. Visual cues like fog and dust all help to make it an educated guess. But it's still just a guess.

And with 48 per cent of cotton growers reporting spray drift damage to CRDC in 2023, it's evident that we aren't always getting it right.

When we don't, the consequences to other growers (from right next door to tens of km away) can be colossal: an average of $855,000 in lost production per grower in the McIntyre-Balonne region last year. The feedback I've had from growers more broadly suggests that figure is the tip of the iceberg, with losses from cumulative inversion drift events easily running into the millions.

WAND can give us the information we need to avoid sending the rig out during a hazardous inversion. What it can't do, is turn the spray rig for home when conditions have deteriorated. That requires a cultural change.

Growers know that the peak time for spray damage is in the lead up to Christmas. For most operators, 25 December is a hard deadline; staff go on leave and no one wants to be on a spray rig, missing the family Christmas dinner. So the boundaries sometimes get pushed.

But you only have to push the boundaries a little bit to cause a lot of problems - and give your neighbours a pretty ordinary New Years present when the damage rears its head two weeks later.

It isn't just Christmas, of course. Modern farming has created a perfect storm: bigger farms, more cropping and less labour makes growers and operators time poor in a way we've probably never been. And when you've got a quarter tank of chemical left and the wind drops away and an inversion sets in - it's tempting to just spray those last few hectares.

But that's where the damage is done. And that's the culture we've got to change.

WAND can't do that on its own, although it's making a pretty good tilt at it. Taking the guesswork out of identifying hazardous inversions is expanding the spray window by an average four hours per day. And WAND's nowcasting function goes a step further - giving growers and operators a two-hour forecast of whether you're safe to go back and refill the tank to keep spraying, or should knock off until conditions improve.

Updated every 10 minutes, nowcast means we're no longer taken by surprise when conditions change; we can plan for it.

WAND is a great tool, and a credit to CRDC, GRDC and Goanna Ag who've put it in the hands of growers. But it will only be a game changer if we all get behind it - and we all make the cultural change needed to prioritise safe spraying.

I love growing cotton, and like most growers I know, I'm always optimistic that the next season will be better than the last. And the chatter about WAND has me optimistic, too.

More growers are talking about spray drift than ever. More growers are becoming aware of the impacts than ever. And more growers are cottoning on to the fact we all have a role to play in making inversion drift a thing of the past.