Raising the curtain on the “spraying” part of spot spraying...figuring out controller rates! - Part 6

It has been quite a journey and I have ruffled a few feathers along the way in my quest to bring some accuracy and precision to the complex art of setting up a sprayer for isolated nozzle operation, that is to say Single-Spot Spraying.

Yes we are all familiar with the WEED-IT and WeedSeeker which existed until recently in their own bubbles. The manufacturers of both have understood the importance of nozzle angles, boom heights and spray widths from the beginning. That is not surprising because that is what they are, dedicated single-spot sprayers plain and simple. Nothing multi or side safetying to see here.

The era of the ‘camera’ sprayers has changed everything. This is marvellous technology for sure and especially the green on green bit, but, and it’s pretty big BUT, simply strapping a camera system onto your boom does not, even if it has the potential to do so, instantly make it into a Single-Spot Sprayer.

Most of the big OEM’s fitting camera systems have failed to do their homework on the spraying part of spot-spraying.

Typically, they will deliver the systems to customers only with nozzles suitable for multi nozzle applications. This is blanket spraying folks, NOT spot-spraying. The configuration and specifications for isolated nozzle application (single-spot-spraying) is completely different!

Quite simply, the blanket rate nozzles supplied are typically too wide and too small for a spot rate application.

Be advised that when you flick the switch to go single-spot, you will be applying a rate/ha less than what you think and wasting most of it anyway due to the unnecessarily wide nozzle angle.

So, in order to get with the program, here is what I am recommending you do;

• Get over it that multiple blanket rate nozzles and isolated single spot nozzles are completely different angles and sizes!
• Find a single spot calculator that will calculate the correct rate/ha for isolated nozzle applications.
  Fantastic Nozzles Spot-Spray Calculator
  It will recommend a suitable spot-spraying nozzle for you. That would be 40° nozzle on 25cm, and 80° nozzle on 50 cm spacings.
• Buy them and fit them up, then
• Set your spray controller at the blanket rate from the calculator (that will have you scratching your head ;) and/or fix the minimum pressure required from the calculator (3BAR), and
• Go spot-spraying in the knowledge that you are doing it correctly ;)

Summary

By now, I thought that the people selling and setting up the majority of these very expensive camera based systems would get it. Some have to a degree but still recommend 80° nozzles on 25cm spacings which as far as I am concerned is wasteful, inefficient and a long way from precise.

And if it's a matter of twists and turns or excessively windy conditions, that is what side safety should be for anyway. Not a thing in itself!

On a positive note, I do have the pleasure of working and conversing day to day with many spot-spraying customers. That certainly helps to balance all the negative stuff I still have to keep taking about.

I will continue to soldier on and spread the gospel according to Dave. Toss away your 110° nozzles for starters and if you do have 80° nozzles on 25cm, set them aside for side safety or blanket applications.

Let’s all get with the program and elevate the spraying part of camera based spot-spraying into realms of precision application where it belongs.

Regards,

Dave

Disclaimer - There may be other systems under development in Australia or information about potential improvements from manufacturers about which I am unaware. If any such information is available, please contact me and I will share it.