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Thursday March 22, 2018

Why farmers use pesticides

From news reports on the possible link between farm pesticides and the mysterious disappearance of bees to the continual publicity machine hyping Environmental Working Group's Dirty Dozen pesticide guide for shoppers, your customers are flooded with assumptions about the use--and potential risks--of pesticides in food production. If the issue of farm pesticide use is so pressing, why do farmers continue to do that?

  • First things first, understand the broad term "pesticides" encompasses a huge variety of products that farmers generally more typically call "crop-protection" and "pest-control" tools, from weed killers to bug killers to animal-parasite controls to fungus-control products; even rat poison is considered a pesticide. Those products range from relatively harmless compounds like natural soaps and mineral oils to potent chemical poisons. (Indeed, some natural pesticides are used even on organic crops and animals.)
  • With that said, why do farmers use them? In all fairness, what the critics say is true, to an extent: Pesticides are used because they're often the most economical method to control the disease organisms, weeds and insect pests that attack farm crops. Farmers spend billions, literally, on pesticides annually, and the direct dollar return on that investment has been estimated to be from $3 to $5 for every $1 spent. But, in equal fairness, it's not all about crass commercialism, either: It's been estimated that food crops must compete with 30,000 species of weeds, 3,000 species of worms and 10,000 species of plant-eating insects, not to mention countless diseases, according to Canada's crop chemical manufacturers' association. In many circumstances, modern pesticide choices are not only the safest way to control those pests--they are the only way. Before the "green revolution" of the mid 20th century, crop protection tools usually included heavily labor intensive mechanical removal of weeds, a few synthetic organic chemicals, and dangerous toxic inorganic materials, including lead and arsenic. Today's arsenal of an estimated 2 billion pounds of chemical pesticides used around the world annually are highly targeted and regulated products that have been heavily researched to attack specific pests with specific doses through a known biological mechanism, and their availability and use is heavily regulated on farms. Herbicides, insecticides, and fungicides reduce crop losses both before and after harvest, and increase crop yields.
  • Because they are the most economical means to protect crops, that economic benefit transfers directly to your food shoppers. The Food and Agriculture Organization of the United Nations estimates between 20 percent and 40 percent of the world's potential crop production is already lost annually--even with the use of pesticides--because of  weeds, pests and diseases. Even after harvest, crop protection products used in stored products prolong the viable life of produce, prevent huge post-harvest losses from pests and diseases and protect food so it is safe to eat. Croplife Canada estimates these crop losses would double if existing pesticide uses were abandoned, significantly lowering food supplies and raising food prices. It's difficult to put an exact dollar figure on the importance of pesticides to making sure enough food is available at affordable prices, but together with fertilizers, improved hybrid seeds, and mechanization, pesticide technology helped increase U.S. farm productivity about 250 percent from the 1940s to 1996.
  • Pesticides also directly help improve both animal and human health by preventing disease outbreaks through the control of rodent, insect and parasite populations and by disinfecting premises like barns, food-handling and manufacturing facilities.

Why consumers are primed to fear food technology

Over the long history of food technological improvements, writes Oklahoma State ag economist Jayson Lusk in a recent issue of the journal Annual Reviews in Resource Economics, consumers and citizens have tended to celebrate, not denigrate, the results. From the discovery of vitamins in 1905 to improvements in rail and truck that moved food better from farm to table, from canning to refrigeration, all those industrial improvements were met with enthusiasm by upper- and middle-class consumers who could be better fed at relatively lower prices as a result.

Today, those same consumers seem to have turned on the technological hand that feeds them, Lusk notes, even to the point of forgoing obvious benefits that are the fruits of that technology. What's happened to change society's attitude? Lusk and his fellow researchers review the scientific literature to make a few educated generalizations:

Risk/benefit analysis has become subjective. Or perhaps it always was, and we've only come to fully recognize that reality. But Lusk notes the old economic model in which consumers and society coldly weighed the benefits of new technology against its risks seems to have broken down in the case of food. People may still weigh the risks, but they do so often blinded to scientific reality by intuition, guesswork and buzz-words.

Complexity necessitates shortcuts. Today's food and farming technology has become so complex, the consumer-behavior research argues, that the average consumer is incapable of either understanding it or of investing the time and effort necessary to think about it rationally. As a result, they substitute emotion, belief and guesswork, often provided by third parties like activists and media and colored by the culture through which they view it.

Consumers apply risk assessments inconsistently. Even in applying those shortcuts to understand relative risks and benefits of technology, current psychological research shows people are wildly scattershot in how they apply that process. Key trigger aspects, like risks that naturally invoke dread because they are uncontrollable, involuntary and potentially catastrophic, can lead them to apply fuzzy math when calculating risk, until a technology that seems completely benign in the cool light of science becomes unacceptably frightening in their hearts (think the very real hazards of organic cigarettes vs. the imagined ones of GMO soy milk, for instance).

Symbolism matters. Even if a new food technology is harmless or low-risk, it often today becomes suspect because it stands for something bigger and scarier. Like a nuclear accident that results in little or no death or sickness but still frightens the public into a harsh anti-technology response, technology like GMO farming can serve as symbol reminding consumers they have little to no control over their food, a similiarly frightening vision.

Any of the research's theories about why consumers distrust food tech could be applied equally well to any new technology, Lusk writes. But they are aimed particularly at food technology today, he believes, because humans have been "hard-wired" through evolutionary development to be skeptical of new foods. "When one is living in an environment where eating an unusual berry or mushroom can kill, nature rewards caution," he writes. For future researchers--and those who apply that research to produce and sell high-tech food--it will be important to better study people's beliefs and how they evolve, how to better communicate risk and benefit within those beliefs and cultural lenses, how sensory input impacts beliefs-based food decisions, and how stated aversion to food technology really translates into buying decisions.

Is organic really more energy efficient?

In her 2010 Diet for a Hot Planet, food-sustainability eco-promoter Anne Lappé predicts a coming "climate crisis" caused by the food system, unless the developed world adopts her seven principles for a climate-friendly diet, including a reversion to old-style farming that replaces petrolium-based energy for more organic forms.

"Implementing climate-friendly solutions--including agroecological and organic methods," promises Lappe, "creates even more beneficial ripples: preserving biodiversity, improving food security and people's health, strenghtening communities, and reducing reliance on diminishing oil reserves."

Then again, maybe not so much, according to a new review scheduled for publication in an upcoming issue of the journal Renewable Agriculture and Food Systems.

The review of about 50 published scientific journal articles showed organic leaves a lot to be desired when it comes to rescuing modern agriculture from oil use:

  • Granted, organic agriculture does consistently show lower energy use than conventional agriculture, writes the study's lead author, British green-food professor Adrian Williams. More than eight out of 10 of the studies he reviewed showed lower energy use associated with organic production. However, that stark difference only appears when you do the math based on the amount of energy used per unit of land. That's all well and good when you're measuring non-market products of agriculture, like biodiversity. But if you're comparing farming systems based on production of goods for market, like food, fiber and fuel, a more meaningful measure is one that compares energy used based on units of production.

  • What happens when you do compare organic vs. conventional farming based on energy consumed per unit of production? The results become "more variable," in Williams' words. "This is to be expected," he writes, "due to the lower intensity of production on most organic holdings, resulting in fewer inputs, and a reduced yield." In other words, organic trades lower energy use for lower yield. Only when researchers create an elaborate accounting system that, in essence, measures the amount of stored solar energy in an entire farm's output, both harvested and standing, does organic begin to approach the energy efficiency ratio of conventional on a pound-per-pound basis. Otherwise, conventional production was found to have the highest levels of net energy production. It's this false organics economy of trading lower use of fertilizer and pesticide for lower food production that has led critics to argue organic cannot sustainably feed the world by meeting current and future demands, Williams grudgingly concedes.

Energy demands of livestock productionEnergy use of organic vs. conventional produce and cropping

Despite remaining an apparent organic advocate because of its promised overall environmental benefits and his conclusion that global petrolium supplies are running out, Williams nevertheless concludes, " their current form, organic systems do not offer a radical alternative to the fossil-fuel reliance of modern agricultural systems. The reduced use of energy in organic production and increased energy efficiency compared to conventional production is often marginal. These systems often still depend on the same sources of (fossil) fuel for tractors, machinery and buildings, etc. While organic production can make a contribution to a more resource-efficient agriculture, in its present form it does not provide a complete solution."

Organic and climate change: A lot of hot air?

Farmer Goes to Market has cautioned before: Blindly following organic food companies onto thin marketing ice by repeating questionable health claims risks the grocer's reputation. In response, critics of modern food technology point to organic as a cure for the environmental pollution caused by modern agriculture, including increasing greenhouse gas emissions and water pollution.

But how well does that claim stand up to scrutiny?

University of Oregon environmental sociology doctoral student Julius McGee tested the relationship between the recent growth in organic agricultural production and greenhouse gas emission that could be traced specifically to agriculture. His study, in the June 2015 issue of the journal Agriculture and Human Values, is one of the first large-scale empirical analyses of certified organic farming and agricultural greenhouse gas emissions. In it, McGee offers the surprising and contrarian conclusion that not only has organic farming not helped reduce greenhouse gases and global warming, it has in fact increased climate change. He believes the rise of certified organic farming has increased both the total amount of greenhouse gas emitted from agriculture and the amount of greenhouse gases emitted per acre of farmland. In addition, he argues that some organic crops--tomatoes, for example--actually produce more greenhouse gases than their conventional counterparts when produced on a similar scale.

How can this be?

McGee calls it a classic example of the "displacement paradox." Rather than replace high-input consumer consumption that may contribute to global warming, organic production simply gives consumers another outlet for purchasing. Organic farming as an alternative to conventional agriculture does little to reduce the consequences of farming practices overall, and organic farming fails to earn its marketing claim as a ‘‘more sustainable’’ form of agricultural, because a link has yet to be established between organic farming and carbon banking that helps reduce levels of greenhouse gas.

"What these findings ultimately suggest is that organic farming is not working as a counterforce to greenhouse gas emissions stimulated by agricultural production," McGee concludes.

Recent news reports have brought the issue of how farmers house their mother pigs, or sows, back into the spotlight. Here are some answers to common reader questions about the use of "gestation crates" or individual stalls for sows.

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