How to manage weeds and off-target movement
Spraying has never been an easy job. Still, it used to be more clear-cut. Just calibrate your sprayer and spray your fields for weeds, fungal diseases, or insects.
That’s changed. City commuters, vineyard owners, and vegetable producers are popping up in your neighborhood. They aren’t going to be keen on having any chemical drift over to their homes or grapes or vegetables. There’s also the possibility of herbicides drifting over to crops that aren’t tolerant of those herbicides. For example, that could include Liberty drifting over on Roundup Ready crops, or vice versa.
Our October 2012 cover story, "Double down on weeds," dealt with the challenge is getting sufficient chemical on to control pests without drifting onto neighboring farmsteads or farm produce.
Bob Wolf, co-owner of Wolf Consulting and Research in Mahomet, Illinois, has developed the On Target Application Academy in partnership with BASF and TeeJet Technologies. He’s conducted workshops with training aids that simulate nozzle patterns and pressure in the field.
Check of spray patterns
A regular check of spray patterns can turn up a scene like this. A poor pattern like this can overapply chemical in some areas and underapply them in others. This can lead to both poor weed control and crop injury issues. Although modern nozzles last longer, poor patterns like this can still result if a sand grain sticks in the orifice of a nozzle.
Uniformly applying chemical through a problem-free nozzle like this one can help slice drift potential and boost pest control. Wolf notes there have been challenges in meeting both goals, but it can be done.
Wolf gives these best application practices for minimizing drift.
-Always read and follow label directions.
-Develop proactive weed resistance management plans.
-Evaluate environmental factors before you spray.
-Select the proper nozzle for best results.
-Calibrate your sprayer.
-Be aware of sensitive crops.
-Keep proper records.
Strategies to reduce drift include:
-Selecting nozzles to increase drop size.
-Increasing flow rates for higher application volumes.
-Using lower pressures.
-Using lower spray boom heights.
-Avoiding high application speeds and rapid speed changes.
-Avoiding adverse weather conditions like high winds.
-Considering use of buffer zones.
-Considering use of new technologies.
Here are some tips for getting sufficient chemical on to control pests without drifting onto neighboring farmsteads or farm produce.