New EPA Restrictions of Herbicide Dicamba, Prone to Drift, Criticized as Not Stopping Major Crop Damage
(Beyond Pesticides, October 20, 2017) Last week, the U.S. Environmental Protection Agency (EPA) announced that label changes to the herbicide dicamba would be made to try to minimize drift that has left thousands of acres of crops already damaged this season. The label changes include making dicamba “restricted use,” which allows only certified applicators to apply the chemical. Dicamba drift has been damaging farmers’ crops for at least two years due to the approval of new dicamba-tolerant genetically engineered (GE) crops. Advocates says that the new changes do not ensure that drift will be eliminated.
According to EPA, the agency reached an agreement with the makers of dicamba, (Monsanto, BASF and DuPont) to restrict its application. This comes after hundreds of official complaints of crop damage related to dicamba across 17 states this year alone, leading to questions about the new formulation of the chemical used in genetically engineered (GE) crop productioon. New GE crops developed by Monsanto must be paired with specific formulations of dicamba, and thus led to a vast increase in dicamba use over the past couple growing seasons. Dicamba-based herbicide use has climbed dramatically as farmers have adopted, especially, Monsanto’s GE soybean seeds; in the 2017 season, 20 million acres of them were planted with the seed.
Farmers who do not use GE seed have seen dire impacts on their crops in the last two seasons, including stunted growth, and wrinkled, cup-shaped leaves. This happens in large part because the herbicide can easily volatilize after being applied and drift via the wind onto neighboring fields. In 2017, more than 3 million acres of soybeans and other crops suffered damage from the chemical.
Beyond the crop damage, pesticides are widely used without, in many cases, rigorous vetting for safety, health, and environmental impacts when used in combination with other pesticides. For example, Monsanto rolled out another iteration of its GE soybean seed in 2015, which is tolerant of both glyphosate and dicamba. Some farmers now use those seeds and “stack” applications of glyphosate on top of early treatment with dicamba, without adequate evaluation of synergistic impacts of the use of both compounds. This also increases the overall amount of pesticides used, and presents an opportunity for organisms that may develop resistance to both compounds — advancing the entropic trajectory of pesticide use. Further, potential synergistic effects of the combination use of these herbicides on non-target species (including critical pollinators) is not typically evaluated by EPA. However, a study has shown that the combination caused damage to the DNA of a toad species.
Until now, many believed the dicamba drift incidents were the result of illegal formulations of the herbicide being applied to fields. But, the extent of damage now being observed contradicts this theory, raising more questions as to whether the new dicamba formulation is actually the cause of the widespread drift damage.
Those who planted these GE soybeans in 2017 must use one of the newer, “low-volatility” versions of the herbicide and follow application directions, but the 2017 season shows that these newer formulations have not solved the drift problem. University and agricultural extension experts report extreme damage in hundreds of fields in their territories, and say that these new formulations remain sufficiently volatile to cause such damage. Non-GE growers have become increasingly angry and vocal about the effects of the chemical, from nearby sprayed fields, on their own crops.
Impacts have been the most extreme in Missouri, Arkansas, Illinois, Mississippi, and Tennessee, where state agencies have fielded thousands of complaints. A map of dicamba-injured soybean acreage shows the most-affected states; several have either instituted bans or tightened restrictions on the use of dicamba. EPA is more than aware of these issues. It held at least three conference calls this past summer with experts and state regulators on potential steps to prevent such damage in coming years. According to North Dakota State University’s Andrew Thostenson, who was on one of those calls, EPA officials said clearly that such damage is unacceptable, and that there would need to be significant changes to the rules on usage of dicamba if it were to be permitted in 2018 (or beyond). The recent announcement on voluntary labeling and protocols is the EPA response. Previously, Missouri and Arkansas have taken limited action against dicamba use.
Now Monsanto and others, after proposing the label changes themselves, are voluntarily agreeing to make the changes for all “over-the-top” (application to growing plants) dicamba products to be used next year. These include:
- Classifying products as “restricted use,” permitting only certified applicators with special training, and those under their supervision, to apply them; dicamba-specific training for all certified applicators to reinforce proper use;
- Requiring farmers to maintain specific records regarding the use of these products to improve compliance with label restrictions;
- Limiting applications to when maximum wind speeds are below 10 mph (from 15 mph) to reduce potential spray drift;
- Reducing the times during the day when applications can occur;
- Including tank clean-out language to prevent cross contamination; and
- Enhancing susceptible crop language and record keeping with sensitive crop registries to increase awareness of risk to especially sensitive crops nearby.
EPA states it will monitor the success of the label changes “to help inform our decision whether to allow the continued “over the top” use of dicamba beyond the 2018 growing season.” However, the fundamental root of the problem continues to go ignored. Restricting dicamba application to only ‘certified applicators’ and other modest changes to applications will not eliminate drift. Continued dicamba use inevitably leads to dicamba drift and environmental damage.
Meanwhile, the chemical companies blame the crop damage on farmers’ misuse, claiming they do not follow directions on application labels, use contaminated equipment, or buy older formulations of dicamba that are cheaper but more prone to drift. Scott Partridge, Monsanto’s vice president of global strategy, insists that drift is not the problem — that “if the label is followed, the product will not move far, including through volatilization.” Of the EPA’s “restricted use” announcement, he said, “We’re very excited about it. It directly address what we found to be the causes of the off-target movement in 2017, and we think it sets the stage for all growers and applicators to have a positive experience in 2018.”
Larry Steckel, PhD, a row crop weed specialist and plant science professor at the University of Tennessee, and Mark Loux, PhD, a professor of horticulture and crop science at the Ohio State University, both suspect that the products’ volatility is the issue. “When you get three or four farmers spraying thousands of acres and it moves and shows the wide-ranging damages we’ve seen, that suggests volatility,” says Dr. Steckel (and Dr. Loux agrees), saying, “It is volatilizing for sure.”
It is no coincidence that with the deregulation of GE dicamba-tolerant varieties by the U.S. Department of Agriculture (USDA) under the Plant Protection Act increased dicamba use, and now increased incidences of drift and damage to other non-tolerant crops. Dicamba has stirred up fights between neighbors in a number of agricultural communities. Bader Farms, which grows over 110,00 peach trees on over 1,000 acres in Missouri, is suing Monsanto after its insurance company issued a refusal to pay for damages caused by off-label dicamba drift from surrounding farms. In June of this year, University of Arkansas’ agricultural research station had over 100 acres of soybeans ruined from nearby dicamba use. Monsanto has defended its new dicamba product, Xtendimax with VaporGrip Technology, resorting to blaming growers for using older versions of dicamba or not following directions on the new product label.
The rise of GE crops has led not only to the proliferation of hard to control, resistant weeds but also increased pesticide use. Pesticides, like dicamba, are highly volatile and drift for miles affecting vegetable and fruit crops that are not tolerant to dicamba. There are reports that the latest dicamba formulation that is used on GE dicamba-tolerant crops (Xtend, Eugenia) is responsible for some cases of drift, and preliminary tests have found that the new formulation does volatilize enough to drift. Until this reliance on hazardous chemicals for food production, especially a reliance exploited by the failures in GE crop technology, is addressed by EPA, more occurrences of increased pesticide use, drift and subsequent environmental and human damage is expected.
Beyond Pesticides has long advocated a regulatory approach that prohibits hazardous chemical use and requires alternative assessments to identify less toxic practices and products under the unreasonable adverse effects clause of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). An approach that rejects uses and exposures deemed acceptable under risk assessment calculations, like acceptable levels of pesticide drift, is needed that instead focuses on safer alternatives that are proven effective, such as organic agriculture, which prohibits the use of toxic chemicals. By strengthening on-farm resources, such as soil fertility, pasture and biodiversity, farmers can minimize and even avoid the production challenges that most GE organisms have been falsely-marketed as solving.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.