Teagasc has confirmed that the spend incurred on spray-applied products on modern crop farms can range from €150/ha to €300/ha and therefore choosing the correct spray nozzle is very important.
Given this level of investment, it is important to ensure that agrochemicals are sprayed in the most effective way possible.
Choosing the correct spray nozzle
Research officer with Teagasc, Dermot Forristal said:
“The role of the sprayer is to get these products applied to the crop as evenly and as accurately as possible.
“On the sprayer itself, probably the most important component is the nozzle tip.
“The selection of the nozzle will determine the correct water application rate, the correct application rate of the chemical being used and the correct spray distribution on the crop itself.”
According to Forristal, the label of the product being used is the first port of call when determining the actual spray nozzle to be used.
“This will give guidance on the required water quality per acre and the required spray size distribution,” he said.
“It’s then a question of picking the nozzle to meet the requirements of the job to be undertaken.”
All spray nozzles today are colour coded.
Flat fan vs low drift nozzle
“For most growers the choice normally boils down to that of using a standard flat fan nozzle or a low drift nozzle,” Forristal continued.
“Air induction nozzles, because of their mode of action, produce much larger droplets that are less prone to drift.
“Air induction nozzles can be used in most situations. But where the target is very small, for example spraying grass with a herbicide, the use of a standard nozzle is advised.”
The Teagasc representative went on to point out that growers should attach both nozzle options to their sprayers.
The decision as to which one can be used for a specific job can be taken on the basis of prevailing weather conditions and crop type.
“But the nozzle will only work if everything else is right,” Forristal added.
Sprayer gauge
Experimental officer with Teagasc, Brendan Burke, stressed the need for the gauge on the sprayer to be working correctly.
He explained that one quick way of checking the pressure gauge, which must be fully visible from the tractor cab, is to attach an O3 nozzle to the boom. When operating at two bar of pressure, this nozzle will deliver 1L of spray in one minute.
“Checking the forward speed of the tractor is also important. All the filters on the sprayer should also be checked on a very regular basis,” he said.