The last thing pesticides or fertilizers touch is the nozzle tip—and a wrong or worn nozzle can cause lost dollars and poor performance.
“Nozzle selection is more critical than it was a few years ago with new herbicides—getting the right nozzle is essential to avoid drift,” explains Tim Stuenkel, Tee Jet global marketing communications manager.
Before your team jumps in the sprayer, ensure they are using the right nozzles for the job and each and every nozzle is in peak working condition.
“Remember, it’s not a one-size-fits-all solution—sprayers have nozzle bodies that hold three to five nozzles for a reason,” says Will Smart, president of Greenleaf Technology. “If you’re going to buy a half-million dollar sprayer and expensive chemicals you want a nozzle that will provide maximum effectiveness.”
Pick the right nozzle for the specific conditions and product.
“Getting the right nozzle tip is the heart of accurate applications,” says Dave Mulder, John Deere product marketing manager. “First, consider what you’re applying and what your goals are from an efficacy standpoint. Also what does the product label require—some more universal chemicals may provide variability but your target pests, diseases and label rate guidelines matter as well as crop type in choosing the best nozzle.”
Follow these steps from Virginia Tech and nozzle experts to avoid confusion and select the right nozzle.
- Read The Label. Taking time to check the label keeps you legal from a stewardship standpoint and can narrow down nozzle options, rate capacity, droplet size and spacing.
“Select the proper type or design of nozzle, which is dictated by the mode of action on the products you’ll use,” says Bob Wolf, owner of Wolf Consulting and Research LLC. “The first two things to check for are if you’re seeking drift control like we are with dicamba or more coverage like what you need with glufosinate.”
- Define Operating Conditions. “Applicators need to know what speed they plan on running—we like a range (say 5 mph to 10 mph) versus just saying 10 mph because speed varies,” says Steve Fischer, inside sales rep and precision expert with Fertilizer Dealer Supply of Boonville, Mo. “Also know how many gallons per acre you want to put on.”
Find your nozzle spacing and spray volume (keep within label requirements), which is especially critical because it influences drift, coverage, droplet size, acres per tank and product efficacy. Then you’ll need to figure operating pressure and an acceptable droplet size. The pesticide influences many of these decisions.
- Calculate Nozzle Discharge. For correct orifice size, consider spray volume, spacing and travel speed. Virginia Tech uses this equation:
Nozzle discharge (gal. per minute) = (travel speed x nozzle spacing x spray volume) ÷ 5940
where: travel speed = miles per hour
nozzle spacing = inches
spray volume = gal. per acre
Today there are a number of apps or websites you can use to enter this information and determine nozzle options—to skip the math.
- Study Options In The Nozzle Catalog. Review spray patterns (such as flat-fan, cone or flood) to determine what’s best for the job. In some cases, you’ll have several nozzle options. In that case, find mid-range discharge rates so the nozzle tips don’t shut off at lower speeds or underapply at faster speeds. This also allows for a range to fine-tune. Greater operating pressure creates smaller droplets, which increases drift potential. If discharge rates aren’t in the catalog you can calculate them with this equation:
psi1 = psi2 x (gpm1/gpm2)2
where: 1= the desired condition
2= the known catalog specifications
Once you narrow down the nozzle size, select the right spray pattern and droplet size, which play a critical role in drift management.
“For example, at Wilger, the 05 style tip has five droplet sizes to go with it,” says Craig Bartel, sales manager at Wilger. “You can adjust your tip style based on the chemicals going through it—that way even if your sprayer needs size 05 tips you can get what you need to spray fungicide or dicamba, which require different tips.”
Droplet sizes vary from fine to coarse. You’ll get better coverage with fine sprays but be more prone to drift. Coarse droplets reduce your risk of drift and could potentially penetrate the canopy better because of their size and weight.
It’s not just droplet size that comes into play. A certain spray pattern will work best for the pesticide or fertilizer you’re applying. Patterns range from flat-fan, which is used for 80% of applications, to more specialized fan, flood and cone-type patterns.
“Application pattern is related to how it covers the plant,” says Dale Kleinschmidt, parts and service location manager for Heartland Ag in Marshall, Mo. “Some liquid fertilizers, for example, recommend a cone for better coverage than a fan spread. Each tip style has its own use.”
Chances are there isn’t one type of nozzle that works for all application jobs—especially as your team has to quickly change out for a variety of chemicals or fertilizers. Maximize the sprayer’s and chemical’s performance by using the optimal tip for each application.
“Everyone seems to be getting new tips for dicamba—that’s because the coverage and flow rate are different,” Fischer says. “It’s different than what they used for Liberty, which recommended a better coverage tip than that of Roundup. Most people just try to keep to two or three tips and only change when forced to—that’s not always the best strategy.”
Make sure you have nozzle tips that fit all of your needs.