Practical, science backed strategies to keep pesticides on target to reduce costs.
February is National Pesticide Safety Education Month, making it the perfect time for farmers to review and strengthen on farm spray practices. Pesticide drift is one of the most common—and expensive—issues affecting crop protection, especially on large farms where broad application areas increase the chances of off target movement.
Recent EPA guidance and Extension research reinforce that while drift cannot be eliminated entirely, it can be significantly reduced through proper planning, equipment adjustments, weather monitoring, and use of emerging technologies.
Why Drift Happens
Pesticide drift occurs when droplets or vapours move away from the intended target during or after application. According to EPA Extension resources, up to 70 million pounds of pesticides are lost through drift each year, reducing efficacy and increasing the risk of environmental harm.
Drift risk increases when:
- Droplets are too fine
- Wind speeds push spray off target
- Temperature inversions trap droplets
- Volatile chemistries evaporate post application
Understanding these conditions is essential for safe and effective spraying.
1. Start With the Label - Legally Required
Every pesticide label includes drift prevention restrictions, such as wind speed limits, required droplet sizes, and application cutoffs says the Pesticide Environmental Stewardship website. EPA guidance emphasizes that following the label is the primary required drift mitigation practice.
In addition, new EPA herbicide and insecticide strategies continue to add spray drift and buffer zone requirements, so always check the most current version before applying.
2. Use the Right Nozzles and Droplet Size
Choosing equipment designed for drift reduction is one of the most effective mitigation steps. Many labels allow drift reducing technologies (DRTs) and specify required droplet characteristics. EPA guidance notes that using certain nozzles, hooded sprayers, or oil based adjuvants can significantly reduce drift and, in some cases, eliminate required buffer distances.
Drift reducing adjuvants (DRAs) are also increasingly recognized by regulators. According to the Council of Producers and Distributors of Agrotechnology (CPDA), they improve precision and help reduce off target movement.
3. Monitor Weather Conditions Closely
Every farmer knows that weather is one of the most important factors in preventing drift.
Labels commonly prohibit applications during gusty or high winds, and EPA guidelines emphasize that applicators must avoid conditions that favour drift.
Temperature inversions—often occurring in the early morning or evening—can suspend droplets in the air and carry them long distances. Montana State University advises that applicators must recognize inversion prone conditions and avoid spraying during these windows.
Key considerations:
- Wind: follow label limits
- Temperature: avoid hot, dry, or inversion conditions
- Humidity: low humidity increases evaporation and drift
4. Establish and Maintain Buffer Zones
EPA spray drift mitigation guidelines require buffer zones in many application scenarios:
- Aerial: 0–320 ft
- Ground boom: 0–310 ft
- Airblast: 0–160 ft Buffers help protect:
- Neighbouring crops
- Waterways
- Residences
- Pollinator habitats
In some cases, the use of specific drift reduction technologies can minimize—or eliminate—the need for these buffers.
5. Add Vegetative Barriers and Windbreaks
Shelterbelts, hedgerows, and CRP strips can disrupt airflow and trap drifting droplets. EPA examples show that vegetative areas may partially or fully substitute for required spray buffers, depending on label requirements.
6. Use Digital Tools to Plan Applications
New tools are making drift mitigation easier and more precise.
PALM: Pesticide App for Label Mitigations
Released by the EPA in 2025, PALM helps applicators assess drift and runoff mitigation requirements based on crop type, geography, and application method. It streamlines compliance by converting label language into actionable recommendations.
Modernized AGDISP Model
A modernization project is improving AGDISP—the EPA’s spray drift modelling tool—to better account for new technologies and site specific conditions. It does not help you now, but it will help regulators make more accurate assessments and may lead to more flexible label requirements in the future.
7. Know Surrounding Land Uses
Every farmers knows the area around them the best. It is important to understand nearby sensitive sites before any application. Certain crops are highly susceptible to low level exposure. Aquatic habitats and residences also require special attention.
Good neighbor communication can prevent disputes and reduce liability.
8. Ensure Proper Training for All Applicators
Farming operations often involve multiple employees or custom applicators. Producers must ensure:
- Certified applicators handle sensitive chemistries
- Applicators know sensitive zones and weather risks
- Workers understand nozzles, droplet size, and mixing procedures
Growers may be legally responsible for drift onto other properties, even when using third-party custom applicators.
Pesticide drift can never be completely eliminated, but farm operations can greatly reduce the risk through:
- Careful weather monitoring
- Proper nozzle and adjuvant selection
- Use of vegetative barriers
- Following label requirements
- Incorporating digital tools
Photo Credit: Pexels - North Carolina Farm Bureau