THE late break to the season has made post-emergent spraying problematic.
But it's a job that has to be done in the absence of a normal pre-seeding knockdown program.
And John Deere said it has made it a little easier with the addition of its optional Exact Apply intelligent nozzle control system.
Last week, AFGRI Equipment, Geraldton, delivered a new John Deere 4060 self-propelled boomsprayer to a northern Wheatbelt farmer, fitted with ExactApply.
And the company's precision ag specialist Craig Harris oversaw the delivery and fitment of the system's components.
ExactApply is based on a Pulse Width Modulation (PWM) system - spraying at a constant set pressure and droplet size, regardless of the sprayer speed and application flow rate.
The operator has the ability to automatically vary the rate across the entire boom, ensuring the uniform application of chemical, even while turning.
The system also reduces the number of nozzles needed because of the increased range on each nozzle and as added bonus, LED lighting on each individual nozzle improves visibility of the spray pattern in low-light conditions.
But like all computerised systems, it's the degree of how much information is accurate that determines the efficiency and 'knowledge' of a computer - the old garbage in, garbage out principle.
Boomsprayer consultant Bill Campbell said that while the ExactApply system was "very clever" providing the ability to "mix and match" (spray nozzles with pressure, water volumes and speed), he was insistent that attention to set-up was vital to produce a desired result.
"The basic principles of spraying technology haven't changed," Mr Campbell said.
"Smaller droplets never make it, bigger droplets give poorer coverage.
"So you should always be aiming for sweet spots."
According to Mr Harris, ExactApply provides sprayer operators with a solution that maintains consistent droplet size and pattern through a wide range of speeds, while reducing the potential for overlaps, skips and drift.
"And the PWM system offers three times the pulsing frequency of traditional PWM systems on a wide variety of nozzles," he said.
There's also the ability to switch spraying between two pre-selected nozzles with the push of a button to increase the range of application to achieve consistent droplet size.
ExactApply is fully integrated with the GreenStar 2630 Display and SprayStar, making it compatible with the entire suite of John Deere precision and data management products.
One major benefit is that operators have full variable-rate and shut-off functionality at the nozzle level (every 38-50cm), which is an improvement over sprayers equipped with John Deere Section Control.
The R4060 itself features a 6000 litre stainless steel tank, a 40m (130ft) carbon fibre boom.
Powered by a 258kW (346hp) 9 litre Deere Powertech engine, linked to a hydrostatic transmission, it is capable of a road speed of 56km/h and also can be optioned with Boom Trac and JDLink.
The R4060 also comes with an optional Solutions Command System, which has been completely re-designed to allow for quick and easy operation at the load station with a 12-button keypad.
The system also features a micro-display, which provides real-time feedback on the system operations, as well as the ability to select a rinse method and the ability to monitor progress during the automated rinse function.
