The resolution of Wu-Smart’s mystery, however, opened the door to a bigger one, and it put her back in the hot spot of neonic controversy that she’d once hoped to avoid. The scandal at AltEn, once it broke, turned a spotlight on the risks of pesticide-treated seeds when they’re used exactly as intended.
Every year, those seeds are deposited in more than a hundred million acres of American cropland. The insect-killing coatings on these seeds are taken up by plant roots and migrate into pollen and nectar; they wash into streams, or persist in the soil. Their effects on the ecosystem are often subtle, but as scientists look for them, they’re finding more and more of them, starting with pollinators like native bees.
A kind of mental and regulatory blind spot once shielded the routine use of pesticide-coated seeds from scrutiny, just as it left state officials in Nebraska oddly uninterested in the thousands of truckloads of seed corn arriving at the AltEn plant. Judy Wu-Smart’s bees helped bring those risks out of obscurity. The battle over what to do about them, though, is just beginning.
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Neonicotinoid-coated seeds spread through American farming twenty years ago. The amazing thing is how long it took for people to pay attention to them. I missed it, too. I interviewed dozens of seed company executives and scientists during this period, and combed through their reports to investors, but neonics never crossed my radar. Like a lot of people, I was focused on a much flashier phenomenon that was transforming the seed industry—the arrival of genetically modified crops.
GMOs didn’t just divert people’s attention. They helped ease the entry of neonics. Companies suddenly could charge top dollar for seeds with novel genes that fought off insect pests and made killing weeds easy. According to USDA statistics, the average cost of an acre’s worth of corn seed soared from $32 to $82 between 2001 and 2010. And as a result, farmers barely noticed, or at least didn’t mind, the extra few dollars they paid for a coating of neonicotinoid insecticide.
“It’s really cheap insurance, like extra insurance in our back pocket,” said Bryon Chvatal, who grows corn, soybeans, and hay in eastern Nebraska. “We put the seed out there hoping for the best, but we’ve got to try and do the best we can to help that seed out.” Applying these treatments, he said, is practically “a no-brainer.”
Before around 2000, relatively few corn or soybean seeds went into the ground accompanied by insecticides. Today, neonics cover the overwhelming majority of corn seeds in the country, and probably half of all soybean seeds.
“It was like, they didn’t exist, and then a few years later they were everywhere,” especially in corn, said Maggie Douglas, an entomologist at Dickinson College.
Curiously, they flooded the market without much hard evidence that farmers actually needed them. The products promised to protect seeds and young plants from pests like wireworms, maggots, or aphids. But they’ve delivered unimpressive results in field trials carried out by scientists at universities, with non-industry funding. Most soybean trials show negligible economic benefit from neonics. In corn, treated seed boosts farmer income in some experiments, but not in others. The difference, in any case, isn’t so dramatic that it would convince so many farmers, practically overnight, to buy seed treatments.
In reality, farmers weren’t really doing the choosing. Seed companies were. In the case of corn, their biggest and most valuable product, the companies simply ran all of their seed through centralized processing plants, covering each kernel with neonics. It became part of the standard corn package, like tires on a new car.
It also left the companies with an expensive hazardous waste problem. According to industry executives, about 10 percent of treated corn seed often remains unsold at the end of the year. Seeds are perishable products, and that unsold, pesticide-coated seed eventually has to be sent to landfills or incinerators.
To understand what drove the neonic phenomenon, I spoke to Mac Ehrhardt, co-owner of Albert Lea Seed in southern Minnesota. Ehrhardt has deep roots in the seed business, but he also looks at it critically, the way an outsider might.
“Do we need to treat all the seed? I think the answer is: No, we don’t,” he told me. Seed companies do it anyway, because of competition: each one is constantly trying to convince farmers that its seed offers bigger, more consistent yields. “You’ve had, in the seed industry, an arms race to maximize seed protection,” he said.
His company is a minor player in that arms race. About two-thirds of the corn seed he sells is organic. But most of the rest is coated with insecticides, just on the off chance that this year might bring an infestation of seed corn maggot or some other pest. “I’m not proud of that,” Ehrhardt said. “But that’s the market that our conventional non-GMO seed competes in.”
Measured by the total area of land affected, neonics are today the most widely used insecticides in the country. “The pattern of neonic use in the United States today is really a 1950s, pre-Silent Spring approach,” Douglas said. “It says, let’s take this incredibly powerful insecticide and use it, in the case of corn, on virtually every single acre, regardless of what pest might be out there.”
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In the fall of 2010, soon after Maggie Douglas started graduate school at Penn State, she went looking for bugs that would eat slugs. Slugs chow down on freshly sprouted crops, and they can be a big problem for farmers. They’re a particular problem for environmentally conscious farmers who are trying to build healthy soil, rich in humus and microorganisms, because it makes good slug habitat, too. Douglas hoped to find natural enemies of slugs that could help keep the pests in check. She set up a small, terrarium-scale experiment with soybean seedlings, slugs, and beetles that she was auditioning for the role of slug predator.
“I came back a couple of days later, and most of the predators were dead,” she said, when I visited her this summer in her office in Carlisle, Pennsylvania. “I started thinking through what might have happened. And realized, ‘Oh, those seeds that I planted in these little terrariums, they were, like, bright orange.” That dye signaled the presence of pesticides, including neonics.
Douglas wondered: Was that chemical coating really so powerful, that it could kill all the beetles? The question led, eventually, to a large field study with a stunning result. Slugs that fed on sprouting soybeans accumulated neonics in their bodies. Being mollusks, not insects, they were relatively unharmed. But it made them poisonous to beetles that do, in fact, feed on slugs. In this experiment, fields in which soybean seeds were treated with neonics had fewer beneficial beetles, more slugs, and produced smaller harvests than similar fields in which seeds were untreated. Neonics were hurting the crop, not helping it.
Meanwhile, researchers were linking neonics to piles of dead bees at hives in Germany, Canada, and the US corn belt. The bees were dying during the spring planting season. Christian Krupke, an entomologist at Purdue University, discovered that widely used planting equipment that employs air pressure to move seeds through the mechanism was blowing dust from seed coatings into the air. He found neonic-laden dust on flowers where bees were foraging, and neonic residues inside bee hives.