The Pollen Predicament

GE Contamination Can Be Costly to Minimize

Emily Unglesbee
By  Emily Unglesbee , DTN Staff Reporter
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The low price tag of non-GE corn seed can be tempting, but consider the costs of keeping GE corn pollen at bay first. (DTN photo by Pamela Smith)

ROCKVILLE, Md. (DTN) -- When it comes to keeping his non-genetically engineered corn as pure as possible, western Illinois farmer Mike Stewart knows the drill.

For a dozen years, he and his family have carefully isolated their corn fields near Monmouth, Illinois, cleaned out planters, combines, bins and trucks and delivered grain directly to barge terminals on the Mississippi River. Nonetheless, two years ago, five loads of the Stewarts' carefully stewarded grain were rejected for GE contamination. The culprit?

Pollen -- and the summer winds that carried it.

The Stewarts lost their premium on those loads and the profit edge it gave them on those acres. Contamination is a nagging problem for growers who opt out of the GE traits that dominate the corn market. As demand for non-GE corn has grown in the past decade, many growers have been tempted to switch, lured by less expensive bags of seed and premiums for the additional management such a crop requires.

However, with 92% of the corn acres in the U.S. sporting biotech traits, that premium isn't guaranteed. End users of the grain will reject loads with varying levels of contamination, generally ranging from 0.9% to 5%, and the cost of keeping levels to a minimum falls solely on the grower.

Non-GE growers have a small bag of tricks to choose from when protecting their corn -- buying certified seed, using buffers, planting later, using different maturity groups, cleaning equipment carefully and communicating with neighbors, and surrounding their fields with soybeans. But pollen drift isn't always under their control.


Between 2011 and 2014, USDA surveys found that organic and non-GE corn farmers lost $6.1 million to GE contamination. The biggest problems often surfaced in Corn Belt states like Illinois and Nebraska.

Corn pollen is quite mobile. A 2003 study from Purdue found that a 15 mile per hour wind can carry it up to half a mile in just a couple of minutes. While the majority of the pollen released in a cornfield typically stays in that cornfield, a small percentage almost always sneaks out. In general, research has shown that a buffer of 660 feet (or 264 rows of corn) will drop a field's contamination levels to 1% or under, but even at distances of 1,640 feet, researchers could not consistently keep levels below 0.1%.

Keeping fields clean of GE contamination is the non-GE farmer's responsibility, a long-lived source of bitterness in the organic community. Crop insurance does not cover lost non-GE premiums, and proving responsibility in such an event can be difficult, so in general, farmers do not get compensated for any losses due to contamination.

As a result, prevention must be a priority. Stewart's grain goes overseas, mostly to China and Japan, the latter of which will allow 5% GE contamination. However, Stewart aims for 1% instead.

"We think eventually it will all be a 1% market, if and when labeling is more standardized, and if we get prepared to do that now and have a good plan, we feel that we can capture that market," he told DTN.

For now, domestic market requirements are solidifying around 0.9%. That's the level the Non-GMO Verified Project requires, and it also serves as the trigger contamination level for the investigation of an organic corn operation, said Laura Batcha, executive director of the Organic Trade Association. Domestic users of non-GE livestock feed tolerate slightly higher levels of GE, at 1.5%, she added.


Keeping your corn in line with these levels can be an expensive endeavor, so farmers setting out to grow non-GE corn should do their math carefully. "Basically, we treat it like seed corn," Stewart said of his non-GE corn acres, which can account for anywhere from 30% to 50% of his corn acreage, depending on the state of local premiums.

His premium options have risen above $1 per bushel for food-grade non-GE corn and sunk down into the mid-20-cent range, where they stand now. According to a USDA report, average non-GE corn premiums plummeted from the 50-cent range in 2013 to just 11 cents in 2014 -- only 3% higher than the average GE corn price point.

While it's hard to estimate the total cost of keeping non-GE corn free from contamination, a 2014 survey conducted by the Food & Water Watch and the Organic Farmers' Agency for Relationship Marketing (OFARM) estimated total losses ranged from $6,532 to $8,500 (a median figure), when you factor in buffer strips, delayed planting, GE testing and other measures. The respondents' median acreage was just 334 acres, however, so costs for larger farmers are likely much higher.


Cleaning out planters, combines, bins and trucks, at some of the busiest times of the farm year, is usually the first step in keeping corn clean.

Depending on your neighbor's crops, you might also have to sacrifice cropland to buffer strips. Stewart also sends 24 to 48 border rows (or 60 to 120 feet) of his non-GE corn into the conventional commodity stream, just to be safe. The Food & Water Watch/OFARM survey found that their farmer respondents lost a median figure of $2,500 on buffer strips totaling just 5 acres.

Yield penalties may also occur. Planting your non-GE corn hybrids later than neighboring corn fields can help limit the overlap between the two crops' windows for pollination, said Peter Thomison, an Ohio State University agronomist. You can also opt to plant a different maturity group to further the likelihood that the fields will pollinate at different times. This system isn't perfect; weather and growing conditions can greatly influence hybrid flowering dates, and companies can have different maturity rating systems, Thomison noted. And of course, spring conditions may give you a limited planting window that you simply have to seize.

Even if you dodge that pollination window, expect a yield penalty from planting late. "You will probably take a hit on yield, but that's the risk," Thomison said.

The Food & Water Watch/OFARM survey pegged the median cost of delayed planting for its respondents at $3,312 to $5,280, a figure that would likely be dwarfed by large-scale commercial corn growers' losses.

Stewart said his fields have never yielded lower as a result of these practices. In fact, in 2014, he placed third in the state in the National Corn Growers Association's yield contest -- with a non-GE hybrid.

But those top yields come at a cost of their own. "It requires intensive management," he said. His non-GE fields get a full dose of fungicides, and he sprays an insecticide to control adult corn rootworm beetles, as well. He also applies a full rate of soil insecticides at planting. "We scout everything," he added. "You have to scout and spend more time scrutinizing your crops and your hybrid performance."

Keeping records of every step of your non-GE corn operation, from purchasing seed to delivering grain to the elevator, is wise, said Jim Riddle, a retired Extension agronomist who now works for the Ceres Trust.

Getting seed clean of GE material isn't always a guarantee, so testing some samples of both the seed and harvested grain might be a worthwhile expense, Riddle said. Stewart said he alerts his seed supplier that his grain will be tested for GE contamination, but "there's nobody who guarantees you down to 1%."

For Stewart, whose family has been growing non-GE corn for well over a decade, the cost of controlling contamination isn't too discouraging. Usually, the lower seed costs in addition to the premium produce profit.

"I always keep in mind my per-acre returns [on non-GE acres]," he said. "But because the yield is equal or better, my return is usually higher and I'm usually better off."

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