Showing this is just around the corner, Drone Spray founder Jono Scott gave a demonstration of his XAG P100 Pro drone in an event organised by a Foundation for Arable Research (FAR) grower group.
Built for spraying and seeding, the drone has a 50-litre tank and can cover up to 14 hectares an hour.
When he started his Christchurch-based business two-and-a-half years ago, his first drone only had a 16l tank.
Mr Scott said broadacre applications such as arable spraying would become more common as drones became larger.
"Drone spraying is on the rise across all sectors and agriculture is no exception," he said in a statement.
The FAR event held at the Dunsandel rugby grounds was focused on future-proofing farm systems. Goalposts, sports floodlights and a surrounding hedge were no obstacle for the flying drone.
"Lower water rates are a key factor to the efficiency of spraying by drone. For some applications we can spray as low as 25% of the water rate of a helicopter operator. This is due to the even droplet size of the atomising spray nozzles and precise, even application.”
In the future, he expected drones and their capacity to get larger as batteries improved. Drones would have more smart technology for applications such as spot spraying of weeds.
Arable farmers will continue to use ground spraying rigs and drones were expected to provide an alternative for aerial spraying.
Drone spraying has the advantage of navigating paddocks with hedges, trees and high wires or when crop or land damage is best avoided. They can also be used at night.
"It is a similar pricing to a helicopter, but more accurate, particularly around the edges."
Before a job is started, an automated flight path is prepared which sets a pre-planned route, boundary limits and no-go areas around obstacles. Height, width, speed and nozzle spray settings can be adjusted during flight.
Mr Scott and his Methven-based colleague Scott Rix can spray a width of 5 to 8 metres, depending on the height the drone is operating.
Drones operate at a height of about 3m for general crop spraying and about 5m on hilly terrain for woody weeds such as gorse and wilding pines, and roof spraying.
The strong downwash from propeller blades ensures the spray reaches the target area.
A spreading and seeding attachment is available for slug baiting, spreading and hill seeding.
FAR technology manager Chris Smith said drones offered another tool in the toolbox and were particularly useful in challenging areas for a ground sprayer.
"While drones have their place and are becoming a commonly used method of application, they may require changes to application rates, which in turn may impact on agchem efficacy and the risk of resistance in pathogen, pest and weed populations. Currently, chemical labels are unable to keep up with technology.”
FAR plans to explore spraying with drones at its Future Farms Systems demonstration site at Chertsey to reduce vehicle use.
A drone is expected to be used on one half of the site adopting a more experimental future-focused approach, while a ground-based boom sprayer will continue on the best practice conventional side.
Mr Smith said water sensitive paper would be used to analyse differences in spray coverage.
Agchem efficiency would also be monitored where possible, he said.
