Pesticides and food: It’s not a black and white issue

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FIRST ARTICLE: Has pesticide use decreased over the last 40 years?

Myth busting: Do farmers ‘drench, douse or slather’ crops in pesticides?

In many articles critical of modern agriculture the narratives about pesticides tend to use terms like “slathered,” “drenched,” or “doused.” These are alarming images and foster consumer fears about the role of pesticides in the food supply. Those actually involved in the control of pests on farms know that these are extremely misleading impressions of how farmers manage their crops. It is useful to make some visual comparisons to provide perspective.

A good example of what it means to “slather”
A good example of what it means to “slather”

“Slather” is a term we use to describe the process of applying a heavy dose of sunscreen. Putting 1/2 ounce of sunscreen on just your face (57 square inches) would amount to 0.009 ounces/square inch. If an acre of a farmed crop were “slathered” to that same degree, that dosage would be more than 54,000 ounces per acre. Most crop protection products are applied in the range of 3 – 64 oz. per acre. That means that the sunscreen slather image is exaggerated by a factor of 850 to 18,000. The use of the term “slather” is completely inappropriate when describing the use of pesticides in agriculture. “Petroleum distillates” (essentially mineral oils) are organic-approved pesticides that are applied at rates up to 1792 oz. per acre. Even that wouldn’t qualify as “slathered” in comparison to the sunscreen.

One reason people may imagine high pesticide use rates are the images of the spraying process. Most pesticides are delivered in a water spray. The actual amount of pesticide involved might range from a few ounces to a few pounds per acre, but is diluted in much more water. To get good spray coverage of something like an orchard crop, it might be necessary to use 100 to 400 gallons of water per acre. To be clear, that spray is almost all water. For something like an herbicide application to a row crop, the “spray volume” might be only five gallons of water per acre, again delivering a few ounces to maybe two quarts (64 oz.) of actual pesticide. How does a farmer’s use of five to 400 gallons per acre of water compare to the emotive terms “drenched” or “doused?”

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What “drenched” really looks like
What “drenched” really looks like

If you get caught in a sudden thunderstorm you might say you got “drenched.” If you were not in the rain too long that drenching might represent five one-hundredths’ of an inch of rain. On an acre that amount of rain would represent 1,358 gallons – far more than even the largest volume used for a crop protection spray.

When you put milk on your breakfast cereal (say ¼ cup to a bowl that is six inches across) you might say you “drenched” it. If that kind of volume were put on an acre of land, it would represent 3,465 gallons – eight to 700 times more than the water volumes in agriculture. Again, “drenched” is a seriously misleading way to describe what farmers do when they spray.

The strange tradition of “dousing” the winner of a race with Champagne
The strange tradition of “dousing” the winner of a race with Champagne

There is a tradition of “dousing” a winning race car driver with Champagne. That seems like a waste of good Champagne, but let’s assume only half of the bottle actually goes on the winner’s head. To apply that sort of volume to a farmed acre would represent 16,148 gallons. So what a farmer might ever apply should really not be described as “dousing” the crop.

Farmers don’t have any incentive to spray more crop protection agent than they need – these products cost money. A farmer also has no incentive to spray with a bigger volume of water than is needed to get the agent effectively delivered.

So when you hear or read about farmers “slathering,” “drenching,” or “dousing” their fields, remember that these emotive terms and mental images are at best, misleading, and frequently, manipulative.

This article originally appeared on Putting Pesticides in Perspective here and was reposted with permission of the author.

Steve Savage is an agricultural scientist (plant pathology) who has worked for Colorado State University, DuPont (fungicide development), Mycogen (biocontrol development), and as an independent consultant. His blogging website is Applied Mythology. You can follow him on Twitter @grapedoc.

21 thoughts on “Myth busting: Do farmers ‘drench, douse or slather’ crops in pesticides?”

  1. Thanks for that article. My personal favourite torture of the English language in the cause of spreading misinformation is using soaked. That one might be applicable to rice fields when they are flooded, but most other crops can’t survive being underwater for too long.

    • Well, we were supposed to be metric by 1995. Then 2015. Now 2025. See where I’m going with this?
      In all honesty, I wish the US would go metric already. Had they started using metric side by side with imperial 20/30 years ago, we could have transitioned by now. There is this fantasy that one day we’ll just go from imperial to metric, which isn’t realistic.

      • Yeah, we’ve been using both systems for about 40 years now. Metric is still akin to a poorly spoken second language for us around here, and probably always will be. Why? Well, we all grew up with inches, feet, ounces, pounds, degrees Fahrenheit, bushels, tons (not tonnes), acres, sections, miles, mph, mpg…

        Converting our legal land measurement to hectares, our metes and bounds to meters and kilometers…oh, whew, that makes me break out in hives just to contemplate it. As it is most of our land deeds and titles go back to when they were measuring in acres, chains & links and rods…from this stone pile to that sycamore tree (both of which are long gone by now). And now we’re gonna convert the whole contentious mess on a parcel-by-parcel basis to hectares and meters? Uh, no, I think not, thanks anyway.

        We live in a land where, for many of us, the seasons are very, very real and temperatures range from intensely hot to intensely cold, with a unique experience in store for us on a daily basis. From childhood, each of us has our built-in thermometers calibrated in degF when doing our outdoor chores. Sure, metric sets itself at “zero” at the freezing point of water, but the point at which puddles crust over isn’t all that special for us. Out here we relate to how deep the cold bites and to exactly what to expect when cranking a John Deere 4430 or a Mack R model E-6 at minus 10 deg F or how it feels to be scouting crops at 85 deg F on a clear day.

        Give me a perfectly reasonable temperature in Celsius and I’m fumbling around with 9/5 fractions and adding 32 (give or take) in my feeble old head, all too often coming up with a comparable Fahrenheit temperature of 113 deg F or some equally absurd result. Damn, then I don’t know which jacket to wear or if I need to hunt up jumper cables and starting fluid or if the field crew will need gatoraide before lunchtime or just what the hell. It’s what I’ve always imagined it must feel like to have a stroke or Alzheimer’s or something.

        You know what they say about old dogs and new tricks. Why willfully set yourself up for disappointment?

        • Back in the 80’s, there was a real push to get us kids to learn metric, which worked fine for me. I’ve grown so accustomed to using both, it doesn’t matter to me either way though I admittedly prefer metric. As far as I know it, they’ve backed off on the teaching of metric to students. There is going to come a day when we finally do, probably around the time the last baby boomer in congress finally keels.
          (side note: why is it drug dealers manage to conduct business in metric, have for years)

          • Yeah, I agree metric will eventually displace our American standard system. Eventually.

            By way of encouragement, Mike, I can report that here on the farm we’ve done our part and have pretty much completely converted from measuring in firkins, stones, furlongs, fortnights, cubits (but we do still measure horses in hands), barleycorns, and poles. So you see, there’s hope. I agree that metric is more logical but that doesn’t make it any easier or practical in everyday use around here. It’s still an exercise in discrete trial and error for many of us when in the farm shop shoulders deep in some dark cavity of some machine to guess correctly whether that’s a 5/8ths or 9/16ths, an 8mm or a 10mm cap screw. ‘Course mixing the two socket sets together in the bottom of a 5 gal bucket of tools doesn’t help, either (heh, see that, even the bucket is rated in gallons). If we were working in a laboratory here the metric system would be the official system, though.

            As for the drug dealers, yeah, they seem to be all in with the metric system, even to the point of preferring 9mm to, say .357 calibre office equipment and routinely cutting kilos into grams, and all that. I think it is because some of ’em aren’t exactly Einsteins, and they at least can catch a glimmer of the concept of tenfold. Oh, and I’m guessing most of ’em are not sentimentalists, all clingy around tradition, or anything. Plus, it seems like most of our illicit drugs, except meth, are imported from places where the metric system has long been the law of the land — hmmm…now that makes me wonder…

          • “but we do still measure horses in hands”
            Even the Brits haven’t given that one up. That may never die. :wink

          • “Mixing two socket sets on the bottom of a 5 gallon bucket of tools”. Jeez don’t I know that. Drives me nuts. LOL.

    • I-19 from Tucson to the Mexican border has been metric for years. It was a first step way back when but exceptional US citizens decided metric was “tooo hard.”

  2. I don’t completely dismiss that the image of actual spraying is of a shower of liquid falling on the crop (and you are right, most of that will be water and very little of the spray is active ingredient), contributes to a perception that people describe as drenching, dousing, etc. However, I believe the common charge that crops are “drenched”, “doused”, “unundated”, “marinated”, “designed to withstand massive amounts of pesticide” (pick your hyperbole of choice) is a logical conclusion that people extrapolate about the herbicide tolerant trait, and not necessarily a graphic description of the act of spraying itself.

    The mental model is this: If crops are genetically engineered to not be killed by a herbicide, then there is no natural barrier to farmers applying as frequently and wantonly as they want to. Theoretically, a farmer could now apply unlimited amounts of herbicide anytime they want to. Therefore, if the trait removes any barriers to the amount and timing of herbicide application, then the purpose for the trait must have been to allow and encourage farmers to apply unlimited amounts. Add to that ht traits are often coupled with a specific proprietary herbicide also sold by the seed company, people are even more inclined to believe that ht traits are a clever, devious means for a company to sell more of its herbicide products by facilitating farmers’ excessive use.

    I suspect most commenters who use those terms are generally clueless about herbicide use prior to ht traits, and vastly underestimate the amount and toxicity of herbicides applied prior to ht traits. They assume prior to ht, relatively little was applied and now, logiocally, quite a bit must be being applied. But, even the most damning indictments of papers such as by Benbrook that attempt to quantify any increase in use does not find doubling, tripling etc of pesticide applications post ht. Even Benbrook claimed maybe 1/3 more than would have been applied without ht. What has most changed is the methodology and timing, i.e. when and how herbicides are applied, and the types of herbicides applied, not whether herbicides are applied.

    Also, the public vastly overestimates the amount and types of products applied post ht traits. As the article points out, the public overlooks that there are both regulatory and economic barriers to excessive pesticide use. I think most commenters do not consider or purposely ignore that there is a point of diminishing returns (if one application of a herbicide provides a benefit in excess of the cost, it does not necessarily follow that a second application provides double the benefit, three applications three times the benefits, etc. If applying 1 lb of active ingredient per acre in an application is effective, it is not necessarily true, and likely not true, that applying 2 lbs / acre is twice as good, that 3 lbs / acre is three times as good, etc.) But I don’t think the public actually calculates an amount, or even associates their hyperbole with spraying imagery. They just think they know that there is nothing stopping someone from applying as much as they want, as often as they want, and therefore logically, the amount applied must be a large amount.

    There was an article by environmental working group about 6 months ago that had a map estimating the amount of active ingredient applied per acre annually. Their map was alleging numbers in the neighborhood of 2-3 thousand lbs of active ingredient per acre annually. Anyone near farming easily recognizes this is wildly inaccurate, similar to if someone told you their car gets 1000 miles a gallon. The cost of applying that amount of active ingredient per acre would be more than the value of the crop, and after at most a couple pounds, anything beyond that would be both agronomically and economically pointless. But to EWG folks and their audience, they perceive no limitations to how much herbicide is applied to ht crops and could believe 1000 lbs per acre. And to them, how close to actual amounts applied their numbers were, even if off by a factor of 10, 100, 1000, was not important because conceptually it was accurate, that ht crops facilitated a dramatic increase in herbicide application.

    • Rick, you’re not being accurate either by such hyperbolic statements as “Theoretically, a farmer could now apply unlimited amounts of herbicide anytime they want to.” That’s not true at all. The amount of herbicide that is permitted (by U.S. pesticide law) to be used on any particular crop is governed by the product label, which is regulated by the U.S. Environmental Protection Agency. Using any amount above the maximum label limit could result in the harvested commodity exceeding the residue tolerance level, thus exposing an offending grower’s crop to impoundment and destruction, as well as civil penalties levied against the grower. Moreover, any grower that gets cited for excessive residues in his crop becomes an immediate pariah in the commodity trade, and a target for future enforcement action. No buyer would deal with him from that point on, and he would be very soon face bankruptcy. Any repeats would result in jail time. These are not trivial matters, and it is irresponsible to suggest that there is “unlimited” usage of herbicides on herbicide tolerant crops. You are correct that growers do not use excessive amounts of pesticides because they are costly, but there are other, equally pressing reasons that they do not, such as I have described.

      • Whoa. That is not my point of view. Read what I wrote again. Maybe I wasn’t: clear, but I was trying to explain my theory of the thought process behind those who allege that farmers drench, douse etc crops with herbicides. The statement you quoted was me paraphrasing what a gmo opponent might think. It was not my thinking. Read that sentence in context with everything else I wrote, including this sentence, ” As the article points out, the public overlooks that there are both regulatory and economic barriers to excessive pesticide use.”

        I agree with every point you made. You and I understand these restrictions. Others may not.

    • I too was perplexed by the hyperbole in your second paragraph. Farmers will not apply more than they need to accomplish the job because weed control is not inexpensive no matter how you look at it.

      One other quibble. You can’t really compare herbicide use from one period to another by looking only at lbs of activity per acre, especially in soybeans. When RR soybeans were launched I believe the imidazolinones had the leading market share and the dose of activity of imi’s per acre is quite a bit lower than Roundup.

      • See my response to Good4U. The author, proposed the theory that people say ge crops are ‘drenched”, “soaked” etc as a hyperbolic description of the act of spraying. I proposed an alternate theory that it is the existence of ht traits that inspires the belief that there are no barriers to how much and how often farmers apply herbicides. When they use those terms, they are not talking about the method of application, but their belief ht traits opened the barn doors to farmers applying wantonly and recklessly.

        The second paragraph was me trying to articulate the mental model people have that leads to them saying crops are ‘drenched, marinated etc. The remaining paragraphs are me explaining why I believe that mental model is faulty.

    • Lot’s of good information in this entire comment thread and all the replies, especially for a lay person like myself, thanks!

      Another issue I see occur frequently is that most people just don’t have a feel or sense for the scope and scale of industrial processes.

      They think that requiring changes to labeling laws, for instance, is a trivial thing. Tell that to the packaging crew that has to perform the retooling for the printing of the labels.

      Or even the idea that farmers can or would just arbitrarily apply huge amounts of pesticide or herbicide now that some seeds are engineered to be resistant. After all they can go to the garden supply store and get a gallon of Round-up for just a few bucks. They don’t get that the “just a few bucks” for a gallon translates to thousands of dollars for the hundreds of gallons they want to accuse farmers of spreading around. This in a business with a tiny profit margin (and don’t get me started on how people don’t understand just how small profit margins on most products are).

  3. In Canada we have gone metric, BUT all of western Canada was laid out on a grid of one mile by one mile, 640 acres per square mile or 1 section. Before the era of big equipment fields were farmed by the quarter section or portions there of. Turn it into hectares but we are still stuck with the confines of the grid system.

  4. Unfortunately, when it comes to cattle and other stock, many products are known as “drenches”, although more recently the tram “pour-on” has become common, and it is a far better word.

    Sheep formerly were dipped – in very toxic chemicals – to kill mites. The areas around the dips are now arsenic-poisoned, but in terms of the land area involved, this may be no more than 1/10th of an acre in a property of ten thousand or much more acres.

    So, drenches and dips are becoming history. Here’s hoping that these words will soon have meaning in an agricultural and stock sense, only when describing historical practice, not current.

    Regarding fruit crops, I’d prefer terms such as fogging where they better describe the reality of the situation.

    This transition is probably best and only driven by the manufactures and sales folk – they change and the others will follow.


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