Its critically important to minimize drift when applying crop protection materials.
Alan James is a Technical Services Agronomist with Mid Valley Agriculture Services, based in Linden, in Stanislaus County. James noted the usual drift issue.
“We get called out all the time by the growers themselves, ‘What are those spots on my leaves?’ and eight times out of ten, it’s drift from the herbicide application they put on, on their own. There is always a little bit, you can’t eliminated drift, you can minimize it,” said James.
James points out some practical strategies in minimizing drift, and not just the obvious of not spraying during heavy wind.
“They need to think about the type of nozzles, the 800 nozzle produce fewer finds than the 110 nozzles, and they came out a few years ago with an extended range, T-Jet extended range nozzle, which allowed you to work at lower pressure and still the coverage,” said James. “And since then there has been at least 2 types of air induction nozzle, where you draw air in, and produce droplets that are bigger because they are wrapped around a little bit of air, and they tend to settle quicker,” he added.
Low pressure is the key, says James.
“You get a good pattern with 15-20 PSI, which produces much fewer finds if you are up at 30-40 PSI. and sometimes they think the higher the pressure the better ill drive it down into the weed, and that has nothing to do with that, it just producing more finds.” said James.
James comments on the scenario of worn out or missing nozzles.
“Every year, you ought to start out with a new set of nozzles, and make sure they are all the same. That is the other thing, when they have weed sprayers got 8 nozzles across the boom, and one plugs up, they have to put in the that plugged one, whatever they got in their pocket. which may or may not be the right size.” said James.