Good Fruit Grower / March-1st 2008 / Evaluating spray ­patterns

 Email  Print  Feed

Evaluating spray ­patterns

Growers can build their own spray patternators.

Researchers use vertical patternators to measure the spray profile and pattern of orchard sprayers, but for growers to purchase their own, the $5,000 to $6,000 price tag has been a bit spendy—until now. Cornell University's Dr. Andrew Landers recently developed plans for growers to use in building their own inexpensive patternator.

The use of vertical patternators is common in Europe because numerous countries require mandatory spray testing each year, Landers said. Vertical patternators work by using a tall mast to collect a spray of water simulating a pesticide application. The spray collectors show how high the spray reached and the symmetry of the left and right side of the sprayer. Dye is used in water to visually evaluate the spray pattern.

As part of Landers's pesticide application technology work, Cornell University has used a MIBO vertical patternator in sprayer trials to evaluate nozzle orientation and spray deposition. Landers has also used the patternator to learn about spray pattern variability of different ­growers' sprayers. In those trials, he has found great variability between different types of sprayers, with many overshooting the tree target.

Improving efficiency

While researchers gain valuable insight when evaluating a sprayer with the patternator, Landers believes it has value for growers who want to improve their spray ­efficiency.

For example, Rod Farrow of Lamont Fruit Farms in Albion, New York, used Cornell's patternator to test the spray efficiency of their tri-fan sprayer, a new type of sprayer from New Zealand. The patternator showed that the sprayer was losing 20 percent of the spray because it was going over the trees. After adjusting the direction of the nozzles to ensure that they were pointed toward the trees, Farrow also turned off 20 percent of the nozzles. This reduced their pesticide costs by $8,000 in a 95-acre block, reported Landers. The nozzle adjustment saved pesticide expenses without affecting fruit packout or quality.

"The patternator can show growers how to adjust nozzles, and it's a great research and teaching tool," Landers said. "But it's too expensive for most growers to buy. So, we developed a patternator that you can build at home."

For about $450, growers can build their own patternator with window-screen material or funnels and 4-inch by 2-inch boards or funnels to collect the spray. Cornell ­University has available plans for two different types of patternators.