Spraying Secrets Unveiled: A Deep Dive for Graingrowers
Spraying is an art, and getting it right is crucial for effective weed control. But here's where it gets controversial: there's no one-size-fits-all approach, and finding the right balance is key.
In a recent GRDC and Facey Group workshop, application specialist Bill Campbell shared his insights with grain producers and operators from Wickepin and Narrogin. And this is the part most people miss: it's not just about the equipment, but understanding the principles behind effective spraying.
Campbell emphasized the importance of coverage, droplet size, and techniques for different situations. "The key is achieving good coverage," he said. "For most Australian broadacre graingrowers, medium-coarse spraying is the sweet spot."
But here's the catch: there are factors beyond our control when it comes to drift. "Spraying is like a chain; break one link, and you risk drift or poor efficacy," Campbell explained.
He highlighted a test he conducted with the Mullewa farming group, where they compared spraying methods using drones, aeroplanes, and self-propelled sprayers. The results? Aeroplanes struggled with excessive evaporation, and drones didn't fare much better.
So, what's the solution? Campbell stressed the need for regular nozzle replacement. "My rule of thumb is to change nozzles every two seasons if you're spraying 5000 hectares annually," he advised.
The workshop also featured a practical demonstration on Luke Landsdale's 3000-hectare property. Landsdale, a Wickepin graingrower, allowed his paddock to be used for a spraying demo, providing a real-world application of the theories discussed.
The verdict? The first sprayer passed with flying colors, but the second needed some adjustments. "We found the nozzles were worn, which affected droplet size and coverage," Campbell explained.
So, what's the takeaway? Effective spraying is a delicate balance of technology, technique, and understanding the principles behind it. And for Australian graingrowers, medium-coarse spraying seems to be the way to go.
What do you think? Is there a better approach to spraying? Share your thoughts and experiences in the comments below!
