Another growing season is just around the corner, and farmers who want to make the most efficient use of pesticides should pay close attention to sprayer maintenance, said an Ohio State Extension expert.

Erdal Ozkan, an agricultural engineer and spraying technology expert with Ohio State University Extension and the Ohio Agricultural Research and Development Center (OARDC), recommends following 10 common-sense tips that will help farmers improve sprayer performance:

1. Calibrate. Applying chemicals with a sprayer that is not calibrated and operated accurately could cause insufficient weed, insect or disease control, which can lead to reduced yields, Ozkan said. Check the gallon-per-acre application rate of the sprayer. This can only be determined by a thorough calibration. Use clean water while calibrating to reduce the risk of contact with chemicals. Read OSU Extension Publication AEX-520 for an easy calibration method: http://ohioline.osu.edu/aex-fact/0520.html

2. Mind the nozzle. How the chemical is deposited on the target is as important as the amount applied. Know what kind of nozzles are on your sprayer and whether or not their patterns need to be overlapped for complete coverage. Make sure the nozzles are not partially clogged. Clogging will not only change the flow rate; it will also change the spray pattern. Never use a pin, knife or any other metal object to unclog nozzles.

3. Avoid streaks. In addition to clogging, other factors such as nozzle tips with different fan angles on the boom and uneven boom height are the most common causes of non-uniform spray patterns. They can all cause streaks of untreated areas that result in insufficient pest control and economic loss.

4. Check the boom. Setting the proper boom height for a given nozzle spacing is extremely important in achieving proper overlapping. Conventional flat-fan nozzles require 30-percent to 50-percent overlapping of adjacent spray patterns. Check catalogs for specific recommendations for different nozzles.

5. Know actual travel speed and keep it as steady as possible. Increasing the speed by 20 percent may let you cover the field more quickly, but it also cuts the application rate by 20 percent. Similarly, a reduction of speed by 20 percent causes an over-application of pesticide by 20 percent — an unnecessary waste of pesticides and money.