The first step in solving any problem is knowing if one exists.

That question remains a matter of fierce debate when it comes to dicamba - a weedkiller that has ignited controversy on farms spanning the country's interior as it skyrockets to newfound popularity in the fight against Roundup-resistant "superweeds." The debate is sure to rage on, as last week the Environmental Protection Agency extended approval of the technology through 2020, with certain new guidelines and restrictions in place.

But while university scientists were able to independently catalog thousands of suspected cases of dicamba-related crop damage tracked by state departments of agriculture last year, some say that political pressure has prevented that from happening this year - muddying the ability to gauge how much damage is or isn't happening, as the technology is rapidly adopted.

"I have no patience for the politics part of all this, and it truly has gotten political," said Kevin Bradley, a professor of plant sciences at the University of Missouri. "There are just too many people who were told they can't give those numbers anymore, as estimates."

As a result, "we're really never going to know what happened in 2018 and how bad it was," Bradley says.

Things were more transparent just a year ago.

As dicamba complaints around the country snowballed in 2017, Bradley established himself as a national leader tracking the issue. At regular intervals throughout the summer, he published updated national maps documenting a state-by-state breakdown of how many damage complaints were being investigated by state officials and how many estimated acres of damage affected soybeans - a crop that is highly sensitive to damage from off-target movement of the chemical.

The 2017 totals reported by Bradley climbed to 2,708 official investigations nationwide, and 3.6 million acres of estimated soybean damage - authoritative numbers that were widely cited in a growing national discussion about dicamba.

Bradley resumed his tracking efforts as the summer heat of 2018 arrived, when warm temperatures make dicamba notorious for evaporating - or volatizing - and moving off-target, where it can damage ordinary plants that are not genetically engineered to tolerate it. His initial report in June showed that for a third straight year, Missouri was well on its way to seeing hundreds of suspected dicamba cases in the state.

But after that early-season report, things ground to a halt. People and agencies stopped reporting numbers to Bradley. Even companies went silent about their field observations, he said.

"Seventy percent of the states that used to respond never gave any numbers," said Bradley. "Everybody kind of clammed up. Nobody wants to talk about it anymore. Even farmers who have been hurt."

Meanwhile, he says the year's incomplete numbers began to be misconstrued.

"I found that a lot of people, a lot of companies, were using the maps to show how great everything was. It was just incorrect," he says. "So we stopped."

He attributes much of the withheld data to the mounting political pressure that surrounds dicamba. The chemical has been an incredibly divisive issue, with many farmers insisting that it is a much-needed tool for weed control, and others saying it can't be controlled in a way that safely coexists with other nearby plants and that they feel forced to adopt it for self-defense. Industry influence plays a role in the debate too, with hefty profit margins at stake for the companies, like Bayer, that produce the weedkiller and accompanying dicamba-tolerant seed varieties.

Even in years past, dicamba cases have been underreported, according to Bradley and others. Sometimes farmers don't bother, as many state departments of agriculture are understaffed to handle the wave of damage reports, with occasionally just a single-digit number of statewide inspectors on hand.

"It's not just Missouri. There's a lot of states that just couldn't have anticipated what they were in for with this," Bradley said. "Never before have they had this kind of demand on their workload."

At other times, farmers have their own reasons not to file formal complaints.

Bradley says some who have sustained dicamba damage told him, "'I'm not going to say anything because I don't want to hurt our chances of having this (technology) in the future.'"

Other farmers kept quiet, Bradley said, because dicamba damage is not covered by crop insurance and reporting it could prevent them from receiving financial assistance tied to other problems, like drought.

"If you turn this in as a dicamba injury in the middle of the season and then it ends up being a drought, that has huge implications for what you can get," Bradley said.

Complaints tallied

Overall, the Missouri Department of Agriculture said there were 216 official complaints of dicamba damage this year, compared to 310 a year ago - when the state had the second-most in the country, behind Arkansas.

But Bradley doesn't believe that fewer reports necessarily mean that there was less off-target movement of the chemical.

"From the chair I sit in, I have a hard time saying it was better," said Bradley. "It just shifted to some different areas."

He said that's true in terms of both geography and in the types of plants affected by dicamba symptoms.

For example, the Bootheel region in southeast Missouri had been at the epicenter of dicamba drama in past years. But the area's soybean fields are now carpeted almost exclusively with Xtend, the dicamba-resistant seed variety introduced by Monsanto and inherited by Bayer.

"Ninety-five percent of the soybeans in that geography are Xtend soybeans. So there wasn't that much to be able to drift onto, because everyone has had to adopt the technology," said Bradley. "As more areas of the state started adopting the technology for the first time, we saw the problems move."

More than 50 percent of this year's dicamba cases in Missouri were in other parts of the state, he said, with northwest Missouri home to the largest number of reports.

With half of this year's U.S. soybean crop now converted to Xtend - and Xtend plantings doubling from 25 million acres to 50 million acres this year, overall - the widespread shift means that the crop is no longer as good of an indicator of off-target movement that occurs. Bradley and others report that much of the continued damage affects trees and specialty crops, instead.

This year's damage comes after extensive training and education campaigns were held for dicamba applicators last winter, aiming to cut down on the issue.

"We had to train everybody last year and I don't think there's any question that helped," said Bradley. "But the areas with the heaviest adoption seem to have the worst problems, still. And we still think there's volatility."

Some of Bradley's dicamba concerns were echoed in recent interviews the Post-Dispatch conducted with farmers and other agricultural experts during this year's harvest.

"Dicamba has still been a big issue," said Blake Hurst, the president of the Missouri Farm Bureau. "Fewer complaints this year, but still out there, still a controversy, still causing some damage."

"We've had some damage from dicamba, and here's the thing: A lot of it gets blamed on the applicators and I know of lots of cases where it's not the applicator's fault," said Dale Samp, a farmer in Cairo, Mo. "It's just a very volatile chemical."

"It's a good product. We like the product, but, boy, it's a tricky thing to use," Samp added. "I'd hate to lose it."

That wish, for two more years at least, has been granted.

On Wednesday, the EPA extended the registration of dicamba for two years, calling the chemical "a valuable tool" for farmers. While the move allows continued "over-the-top" spraying on corresponding varieties of soybeans and cotton, it also called for additional safeguards and restrictions.

Perhaps most notably, the agency ruled that "only certified applicators may apply dicamba over the top," and that restrictions would also apply to the timing and frequency of the chemical's use. For instance, dicamba can only be sprayed on soybeans within the first 45 days after planting.

"This continued registration, based on an extensive review, keeps this much-needed weed control tool in the hands of growers," said Ryan Rubischko, Bayer's dicamba portfolio lead, in a statement. Going forward, he said the company would work closely with growers, regulators and others to ensure "continued success" for the chemical's use. It has strongly denied that there are any inherent flaws with the technology.

Some outside experts expressed skepticism as an initial reaction to the EPA announcement.

Bob Hartzler, a professor at Iowa State University who has closely followed dicamba issues, wrote that he saw "very little value" in the seasonal restrictions the agency outlined. He worries that the cutoff date is too late, especially given the later planting dates in northern regions.

"Applications would be allowed into July for much of Iowa's soybean acres," he said. "In 2017, 90 percent of dicamba misuse complaints to (the Iowa Department of Agriculture and Land Stewardship) were associated with applications made after June 15. I believe a date restriction would be more appropriate, (and) a date in mid-June would be my preference."

Hartzler expressed concern in other areas, too, saying that "numbers don't suggest the classification of applicator has a big influence on the likelihood of off-target movement."

"Unfortunately, I don't think these new restrictions will have a significant impact on the problems we've seen the past two years," he concluded. "I was hoping for something similar to what Minnesota did in 2018, a date and temperature cutoff for dicamba applications on Xtend soybean."

States are still able to implement their own additional restrictions - or altogether bans - if desired. The Missouri Department of Agriculture said it was too early to determine whether it would pursue further actions.

Bradley said instead of continued fights about the volatility of the product, his research has shifted its focus to learning how to minimize it, by examining the effects that the pH of soil and spray tanks can have on the chemical's tendency to move.

"We no longer are going to waste our time arguing whether there is volatility," he said. "We feel confident that there is volatility occurring so we started looking at what we can do to minimize it. ... You'll see more of that stuff coming out to minimize the problem that we believe is there."

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