On Target

06/01/2010 02:00:00 AM
Vicky Boyd, Editor

Dozens of growers nationwide have had their air-blast sprayers evaluated to ensure they’re putting out the right pesticide rates and aren’t contributing to drift with improper spray patterns.

But the high-tech machines used in the evaluations are expensive and cumbersome to transport. And growers outside of the test regions may not have access to them.

Andrew Landers, a pesticide application technology specialist with Cornell University in Geneva, N.Y., has a solution. He has designed a patternator, which produces results similar to the spray pattern evaluations and only costs growers about $400 to build.

Build your own patternator

A patternator typically is a wall of catch-cups or screens that shows the pattern produced by an air-blast sprayer.

Based on the resulting pattern, the operator decides whether to turn off nozzles on the bottom or top of the sprayer or adjust nozzles that are pointing in the wrong direction.

The goal is to apply the product to the tree and not underspray or overspray the canopy, thereby reducing drift.

After seeing the high-priced models in action, Landers built one out of materials commonly available at home centers and lumber yards.

In a 2004 trial, he pitted his machine against one designed by Emilio Gil, a visiting professor from the Universital Politecnica de Catalunya, Italy, and a $4,000 Italian-built MIBO patternator. Gil’s UPC unit cost about $800 to build.

All of the machines produced similar results.

Landers reports that his unit reduced drift by up to 90 percent and pesticide use by up to 20 percent.

Since he released the original design in 2004, Landers says he knows of dozens of growers who have built their own. He also knows of at least one grower who has modified it to bring the cost down to less than $400.

To download the free plans to build Landers’ patternator, visit http://www.nysaes.cornell.edu/ent/faculty/landers/pdf/Patternator.pdf

Raising drift-prevention awareness

Jon M. Clements, a University of Massachusetts Extension Tree Fruit Specialist based in Belchertown, obtained a two-year, $63,000 grant from the Environmental Protection Agency’s Region 1 to help New England apple growers reduce spray drift.

As part of his efforts, he bought an Italian-made successor to the MIBO patternator that he admits is probably more expensive than most growers could afford.

But he says Landers recommended the unit because it is sturdy enough to haul to field days for demonstrations and to test multiple growers’ sprayers.

Landers’ home-built patternator is fine for use on an individual farm, but it may not withstand road trips and intensive use associated with field days, Clements says.

In addition to the patternator, Clements says he uses a bench-quality pressure tester and a flow meter to measure nozzle output.

Both the pressure tester and the flow meter produce quantitative data whereas the patternator results are more qualitative, he says.

If a nozzle is rated at so many gallons per minute and isn’t meeting that rating, the results are numeric. The nozzle may be worn and is putting out more than the rating or may be clogged and putting out less.

The results of a patternator are more open for interpretation, Clements says.

Although he’s in the first year of his grant and has only conducted a handful of field days, Clements says growers seem more interested in the flow meters than the patternator.

“With the flow measurements, if a nozzle is clogged, you get a very quantitative response,” he says. “There’s more interest in that than in the patternator. With the patternator, there’s no real right or wrong.”

Regardless, he says the demonstrations have raised interest in drift reduction and prevention.

“After you get done doing it with growers, I think they have a much better comprehension about how to do it,” Clements says. “If nothing else, just raising the awareness in both New York and here in Massachusetts, and I did that field day up in New Hampshire. Just exposing growers to it will be helpful.”

Doing a better job

Clements also has enlisted Mo Tougas, owner of Tougas Family Farm in Northborough, Mass., as a grower mentor for the project.

Tougas, who has about 90 acres in fruit, put his sprayer to the test years ago and has continued to make upgrades since then.

He’s added a TeeJet computerized rate controller that adjusts the spray flow as the driver speeds up or slows down.

Tougas also has installed hydraulically powered fans on his spray tower so he can better control the amount of air flow. In addition, he has changed the angle of the fans, pointing them downward so they hit more of the canopy and don’t spray into the atmosphere.

The impetus behind the retrofits has been partly financial and partly environmental, Tougas says.

“The materials we’re using today are much more expensive than they ever have been in the past and much more specific to the targets,” he says. “It used to be the materials were really broad spectrum. We just need to be able to do a better job with the application techniques.”

The need for basic maintenance

The Clovis, Calif.-based Coalition for Urban/Rural Environmental Stewardship, has helped dozens of California growers make sprayer adjustments to reduce drift.

With the help of a $75,000 grant from the State Water Quality Control Board, the non-profit group purchased a Pessl sprayer tester in 2005 and has conducted about 100 sprayer evaluations since then, says Parry Klassen, CURES executive director.

The Austrian-built Pessl Sprayertest 1000 measures individual sprayer nozzle output as well as the overall spray distribution pattern.

After sprayer testing, participants saw an average improvement in nozzle output of 21 percent, Klassen says.

Most of the participants brought their sprayers directly from the field for testing.

A nozzle test stand measured individual nozzle output.

“Often we would find a clogged nozzle or worn out sprayer disc,” he says. “After they changed those, that alone helped improve the efficiency an average of 10 percent. What it revealed was there was a need for basic maintenance.”

A vertical test stand evaluated the spray pattern.

The actual improvement in spray deposition depended on the tree shape and size, Klassen says.

CURES also loaned the test rig in 2009 to Washington State University, where more than a dozen growers had their sprayers evaluated at Integrated Pest Management field days.

Contact Vicky Boyd at vlboyd@at.net or (209) 571-0414.

Comments (0) Leave a comment 

e-Mail (required)


characters left

Feedback Form
Leads to Insight