California growers are under increasing pressure to control off-site movement of applied pesticides from their farming operations. A number of new or draft state and federal regulations are targeting crop protection products and spray drift, particularly if they are applied near surface waterways or schools and other sensitive sites.

IN ORDER TO reduce spray drift, farm advisors suggest spray rigs drivers should not exceed 2 mph during application, which also increases spray efficacy.

The Environmental Protection Agency recently released new draft language for spray drift on pesticide labels, marking the third time in the last decade that EPA has tried to change label language related to spray drift.

This new language would expand the definition of drift to include any off-site movement, and enhance enforcement powers related to drift onto sensitive sites. Based on the comments received, EPA may make revisions before finalizing the language that will be standardized across all labels.

In addition, to comply with the Endangered Species Act, EPA recently announced variable buffer zones to avoid drift of three organophosphate pesticides (chlorpyrifos, diazinon and malathion) to protect endangered salmon and steelhead in California, Washington and Oregon. The buffer zones for these three OPs apply to any waterway that can reach salmon-containing waters, including irrigation ditches, canals and tributaries. This currently includes waters leading to the Sacramento River, but could also include the San Joaquin River if endangered salmon runs are restored as expected under a recent federal agreement.

A new concept is the requirement for growers to visit a Web site (epa.gov/espp/litstatus/wtc/uselimitation.htm) to calculate the required buffers and growers must retain documentation verifying that they reviewed the Web site prior to application. The size of the buffer will depend on the rates applied, size of the waterway, droplet size, etc. The new labels are expected to be out this season.

At the state level, the Department of Pesticide Regulation is holding informal public discussions about how to reduce the level of pesticides that end up in surface waters. Among the proposed remedies being discussed are mandated buffer zones of 150 feet for airblast sprayers.

The Almond Board of California (ABC) continues to support resources and research to help almond growers control off-site movement of applied pesticide through drift. Production research over the last 30 years has helped growers transition to integrated pest management and reduced risk compounds. The ABC’s Environmental Committee has been supporting the proper calibration of aerial sprayers, and ABC continues to support outreach on reducing spray drift through groups such as the Coalition for Urban/Rural Environmental Stewardship (CURES).

Through these types of efforts, best management practices for reducing spray drift have been developed, which can be found on the ABC Web site at almondboard.com.

Among the specific factors we know almond growers can and are taking into account to reduce spray drift:

• Wind speed. Pay attention to wind speed. Avoid applications in winds over 10 mph.

• Droplet size. Use the largest droplet size possible to the extent the application will still be effective.

• Tractor speed. Farm advisors suggest spray rig drivers not exceed 2 mph during application. (This also increases spray efficacy.)

• Calibration. Make sure the spray rig is calibrated so that nozzles are properly aimed at their target.

• Sprayer technology. Use smart spray or other technology to reduce material use and direct it at the target where possible.

• Awareness. Watch for sensitive sites, such as surface water, and avoid spraying from the inside out of the orchard. Also be sure that nearby flowering plants, houses, humans, or other sensitive areas are protected from spray drift.

• Communication. Train and communicate with the spray rig driver so he knows to take the above precautions into account before operating the rig.

The good news is there have been a number of successes to show that these best management practices can pay off. CURES has made a concerted effort through the East San Joaquin Water Quality Coalition to visit with individual growers who farm land along waterways where water quality monitoring has detected pesticide levels in exceedance of current standards.

Growers there have taken steps to keep applied pesticides out of waterways, and as a result, recent routine water sampling shows marked improvement in water quality. The hope is that despite regulatory pressure, these successes will help ensure growers continue to have important crop protection tools available to them to control pests in the orchard as needed.

For more information on water quality, go to almondboard.com.