Last week, the U.S. Environmental Protection Agency approved the use of a new herbicide program, Enlist Duo, to fight chemical-resistant “superweeds” in several states, including Ohio. Many say it will help corn and soybean crop yield significantly, while others worry it also will create stronger superweeds, along with increased human health and environmental problems. Here are some of the things to know:
1. How superweeds came to be. Weeds compete with food crops for nutrients in the soil. In order to control them, especially on vast farms, farmers started planting genetically modified corn and soybeans that were resistant to certain weed killers. Then they could spray to kill weeds without killing the food plants.
But weeds adapted, developing resistance to the herbicide. New GMO crops were developed to resist a stronger dose of weed killer. Now that chemical mix, Enlist Duo, is being allowed in six states, with ten more states being considered. Farmers are expected to start using it this spring.
2. Superweeds are spreading. Earlier this year, Ohio State University Extension sent out a notice that superweeds or “pigweed on steroids” were marching into Ohio, possibly as far north as Columbus. In some species, one plant can produce more than a million seeds. Some extreme infestations in other states have caused entire cotton and soybean fields to be mowed down, said OSUE weed expert Mark Loux.
“I don’t think we can be too alarmist about these weeds,” he said. “They could make our current problems seem relatively minor.” He recommended monitoring for early intervention, using herbicides correctly and everything from tilling to mowing to “pulling the plant out by hand.”
3. Some farmers welcome the new weed killer. Tests on Enlist Duo were done in several states, including Ohio, with many farmers hailing it as effective. “It does what it says it’s going to do,” Delaware farmer John Davis said in a Dow Chemical video. An Ohio Country Journal story said farmers were happy with the product but at least one – who may or may not have been the same John Davis – said he was unhappy that it took several years to get approved. The cost of that testing and legal testimony, will likely be passed to farmers, he said.
4. Some groups oppose it. They say introducing a stronger herbicide will only create stronger superweeds. Other, more organic methods of farming are recommended. Scientific American said in an article last week there has been broad opposition to the product’s approval, with more than 400,000 comments to EPA.
“Critics say use of 2,4-D (a component of Enlist) has been linked to a range of health problems, including reproductive problems, non-Hodgkin’s lymphoma and Parkinson’s disease,” the magazine reported. Enlist Duo also includes glyphosate, the main ingredient in the widely available weed killer, RoundUp.
Ohio Ecological Food and Farm Association, the leading organic advocacy group here, opposed both the GMO corn and soybean seeds resistant to Enlist Duo, and the herbicide itself. “The definition of insanity is doing the same thing over and over, and expecting a different result,” said Amalie Lipstreu, policy coordinator for OEFFA. “We must stop this dangerous chemical treadmill, which is threatening public health, our environment, and the future of agriculture.”
5. A lot has yet to be resolved. The EPA has given permission for the use of Enlist Duo, but only with several first-time conditions. Dow must monitor and show weeds are not becoming resistant to the herbicide. Farms must supply a 30-foot “no-spray” buffer zone around application areas and not apply it in winds more than 15 miles an hour.
The EPA will review its approval of the chemical in six, rather than the usual 15 years. Doug Doohan, a Wooster-based researcher for OSUE, told Ohio Country Journal that the conditions applied by the EPA were significant. “However,” he added, “I don’t believe that these developments eliminate risk, and I predict that incidents of damage to sensitive crops will increase, at least during the first few years. My guess is that settlements will be harsh on the offenders and, over time may, bring the incidents of drift (the chemical moving through the air) back down.” The U.S. Department of Agriculture has also announced programs to educate farmers about weeds, and about more holistic methods of dealing with them.