Don't let pesticides drift off target

Joel Kangiser
Pesticide Management

Para español

Measuring nozzle output, as practiced in a WSDA training
for pesticide applicators. 

As crop-planting and growing season gets into full swing, now is peak time for applying pesticides across Washington agriculture country. Pesticide applicators are responsible for assuring that pesticides do not drift off target.

Last year, WSDA’s Pesticide Management Division investigated 165 incidents involving potential violations of the state’s pesticide laws and 60 of those involved allegations of pesticides drifting onto neighboring property. So far this year, WSDA has received four complaints of pesticide drift and most involve potential human exposure. All are currently being investigated. Though this number is lower than previous years, the late spring will bring on more spraying with the potential of drift.

To ensure that pesticides do not drift beyond the intended treatment area, WSDA offers the following suggestions to reduce the risk.
• Read the label on the pesticides being applied and abide by all precautions and restrictions on safe handling, necessary protective equipment, buffers, the effect on crops and more.
• Pay special attention near sensitive areas such as highways, homes, schools and other occupied dwellings or where workers are present.
• Properly calibrate equipment, using the proper nozzles and pressure to keep the spray on-target.
• Based on the amount of foliage and tree size and shape, optimize your sprayer by using the appropriate volumes of water and air, and the correct pressure and nozzle size.
• Scout the areas bordering the place that’s being treated.
• Evaluate conditions such as wind speed, wind direction, and temperature. Do not spray during a temperature inversion.
• Stop applying immediately if conditions change in ways that increase the risk of drift to unsafe levels or if anyone approaches the area without proper protection.

Illustration of the steps to calibrate a sprayer, from a
WSDA training presentation for pesticide applicators.

WSDA licenses about 28,000 pesticide applicators, dealers, consultants and inspectors. Licensees are trained to apply pesticides safely. If problems do occur, WSDA will investigate complaints that allege the state’s pesticide laws have been violated -- including cases of drift, worker exposure, or environmental harm.

If you need assistance calibrating and configuring your airblast sprayer, please contact WSDA’s Technical Services and Education Program at: (509) 249-6939 or  by email.

To file a complaint, email pesticide compliance or call toll free to 1-877-301-4555. When you call, have as much information as possible ready to share with the investigator.

The state Department of Health investigates potential cases of pesticide illnesses. Visit their website for more information.