Pesticide Drift and Communication

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About Jason Deveau (Spray Guy)

Dr. Jason Deveau has been the OMAFRA Application Technology Specialist since '08. He researches and teaches methods to improve the safe, effective and efficient application of agricultural sprays in specialty crops, field crops and controlled environments. He is the co-administrator of Sprayers101, co-author of the Airblast101 Textbook, a slow cyclist and an even slower runner.

See all posts by Jason Deveau (Spray Guy).

When it comes to information about mitigating pesticide drift, it’s plentiful and easily accessed. I have an archive of >30 articles written by Ontario Ministry of Agriculture staff spanning 1999 to present day. Many are on this website. In fact, there’s so much good information out there it feels like there’s nothing left to say. As a connoisseur (and author) of such materials, I have noticed four common themes – see if you recognize any:

  • The Carrot: These articles describe the benefits of reduced drift, like solid neighbourly relations, reduced environmental impact, saving money in wasted pesticide and improved spray coverage.
  • The Stick: These articles feature insurance adjusters or regulators providing statistics from case studies on the financial, legal, and insurance impacts of drift. Not to mention the time it takes to deal with these issues.
  • The Heart: Many articles describe the frustration and emotional impact from the driftee’s perspective. Others chronicle the conflict, irritation and personal insult that come from being accused of drifting.
  • The Facts: Here we have technical specialists laying out math, such as weather models describing spray behaviour, buffer zones and drift reduction technologies like nozzles, shrouds and sprayer calibration.

Beyond the written word there are also videos, PowerPoint presentations, workshops or demonstrations, government fact sheets, marketing brochures, social media content and smartphone apps. And yet, every May-July, the drift complaints seem to roll in regardless. For those that ask “why?” here are a few possible reasons:

Why drift happens:

  • Maybe the sprayer operator is pressed for time and chooses to ignore best practices in an effort to catch up. Haste can lead to mistakes.
  • Perhaps the sprayer operator is new and inexperienced, or falls in that small demographic without ready access to educational resources like ag. meetings or the internet.
  • Maybe the operator is a veteran lulled into false security having successfully sprayed so many acres, for so many hours, for so many years. Why be so diligent when nothing bad ever seems to happen?
  • Maybe the problem stemmed from bad communication. Perhaps the land is rented by one person, to a farmer that isn’t there, who has their fields sprayed by custom applicators, who don’t know what’s around the field.
  • Or maybe even the best-intentioned sprayer operator can have bad luck.

Where can drift take place?

Agricultural spray (i.e. field crop or horticulture) has the potential to move between operations, or onto residential areas, or sensitive environmental areas. A single operation can even drift an incompatible chemistry onto itself.

There are also residential applications (e.g. lawn care) that can negatively affect neighbours. Industrial applications such as roadside sprays can drift to agricultural or residential. Even organic operations spray products that can move outside the treatment area if conditions allow.

It is important to recognize that every single spray application has the potential for off-target movement. That’s why it’s so important to know what and who is around the treated area.

Communication helps

Communication between neighbours can make a big difference, both in preventing drift damage and resolving matters should an incident occur.

Here are two perspectives on the same chemical trespass incident. In the first, the parties do not know, and do not care to know, one another. In the second, the parties have communicated previously. Which scenario will be easier to resolve?

  1. A “field cropper that drives 20 miles per hour in high winds” is contacted by a MECP officer on behalf of a “vegetable grower that’s always complaining about spraying”. Accusations and defensiveness between the two parties prevent them speaking directly. Specialists, adjusters and the officer find themselves acting as mediators. The process is slow and likely headed for court.
  2. Sarah knocks on Kevin’s door and says there might be something wrong with her crop – can he come have a look? She has (rightfully) contacted the MECP to collect samples just in case, and Kevin has all his spray records so they can figure it out. They call in a crop consultant and she contacts a university specialist to solve the problem and prevent it happening again. They follow the crop to yield to determine the impact.

Regarding Scenario 1, it’s not my intention to slander field croppers or horticulturalists; I have actually heard parties involved in highly emotional drift disputes describe one another this way. My intent is to point out that you cannot label an entire industry based on the actions of an individual. When parties see each other in this fashion they are unlikely to work together to resolve the problem. No one will be satisfied with the outcome.

Regarding Scenario 2, I have observed that once each party has a face and a name, it’s so much easier to find solutions. It doesn’t mean someone wasn’t at fault or that compensation isn’t required, but the dialogue facilitates a faster, easier and less emotional outcome. Obviously, in the case of repeated or large-scale incidents, communication may not yield satisfactory results. I’m hopeful, but not naive.

Opening a dialogue

Communication can be initiated from either direction: An applicator can inform a residential neighbour or fellow farmer with sensitive crops when and what they intend to spray. Likewise, the neighbour or sensitive crop grower can reach out to the applicator to let them know they are there and that they are concerned.

There’s no need to wait until there’s a problem. Both parties benefit from keeping one another informed about when sprays go on and the state of any sensitive crops. And, if there is an issue, both parties should begin documenting conditions and suspected damage as soon as possible and over time during the resolution.

Final thoughts

So, the core of this article isn’t how to prevent drift, or what to do if you suspect it. That’s all been said and I’ve listed a few resources for reference at the end. This article is about being aware of drift potential and about opening lines of communication between those that share borders.

So follow the links below to learn more about what you can do to mitigate drift. Then, go introduce yourself to your neighbours. Bring a pie. Everyone loves pie.


  • Article – This link includes four videos and a factsheet about what drift is, how to prevent it and what to do if you suspect it.
  • Article – This link includes a video and a factsheet about surface inversions and drift.
  • Article – Spraying in the wind.
  • Video – The time of day can affect drift potential.
  • Video – Spray quality (i.e. droplet size) and how it relates to drift.
  • Two articles (one and two) on reducing travel speed and employing other means of improving productivity.
  • Article – Drift-reducing nozzles.