TRIPLE rinse your sprayer tank as well as your empty pesticide packs to minimise the risks to crops and people.
That is the advice from Bill Taylor, field research co-ordinator for sprayer manufacturer Hardi International.
Freshwater flushing tanks and tank wash systems do a good job and can be retrofitted to sprayers. Using them to flush out the sprayer tank and booms in the field as soon as a job is finished means contaminated waste is not taken back to base, notes Mr Taylor.
When using sulfonyl-urea-based products adding an additive, such as all Clear Extra or Tanksafe, and following manufacturer instructions is important. But such cleaning agents could be equally useful for cleaning other pesticides and oily deposits from tank, boom, hose, filter and nozzle.
But take care not to mix ammonia-based cleaners with those containing a bleach or chlorinating agent.
"It is also important to avoid spilling undiluted product on aluminium alloys, zinc or galvanised surfaces. Using an induction filling bowl will minimise this risk," points out Mr Taylor.
"Remember, sprayer and boom contamination is not only internal – the outside fabric gets a build-up of pesticide after several jobs too. It is good practice to regularly clean the outside of the sprayer as each job is completed."
In the field, ensure an area of the last treated crop receives less than the full permitted product dose.
When spraying is finished, one-third of the flushing water and the recommended rate of cleaning agent can then be thoroughly circulated and sprayed out on the crop.
Another third can then be introduced, circulated and sprayed out. Lastly, the last third is used to wash down the sprayer, booms and rear of the tractor – using a dedicated sprayer hose with a long handled car wash brush or a flushing flat fan spray lance. *