USDA is ready to say that one corn variety and two soybean varieties resistant to the herbicide 2, 4-D should be deregulated for commercial use.
Before that can happen, however, USDA’s Animal and Plant Health Inspection Service must open up a 45-day public comment period for people to review APHIS’ study of the environmental impacts of corn and soybean crops resistant to 2, 4-D.
A petition by Dow AgroSciences seeks to deregulate the seed traits. If the petition is granted, APHIS would no longer require permits to grow or ship the seeds across the country.
On Friday, APHIS released its 204-page draft Environmental Impact Statement on the impacts of deregulating the seeds, as required by law. The gist of the report is the seeds themselves would not pose a plant risk, but increased use of 2, 4-D could mean more weeds would be resistant to that herbicide in the future.
With the draft report, USDA opened up a 45-day comment period for people to comment on the findings of the EIS.
Farmers are more interested in possible 2, 4-D varieties specifically because of herbicide-resistant weeds. APHIS noted different varieties of herbicide are needed because the “nearly exclusive use of glyphosate over the past 15 years” led to the development of glyphosate-resistant weeds.
APHIS stated markets for 2, 4-D corn and soybean seeds would strongest in southern states and fringes of the Corn Belt.
The herbicide 2, 4-D is already an active ingredient in hundreds of other herbicide mixes, commonly used in lawn-care products, APHIS noted. It is the third most-widely used herbicide, behind glyphosate and atrazine.
Corn carries some natural tolerance to 2, 4-D in early stages of growth. The Enlist traits allow farmers to apply the herbicide when the corn is more mature, APHIS stated.
Soybeans, however, are sensitive to 2, 4-D, so the herbicide can only be applied at least 30 days before planting the crop. Enlist soybeans allow farmers to apply the herbicide postemergence. “Consequently, Enlist soybean will be valuable to control the many weeds that begin to grow later in the season after the soybean has begun to grow,” APHIS stated.
The APHIS regulatory notice posted in June has not garnered significant opposition. Only 48 total comments have been posted on the APHIS action. Most of those comments also focused on the herbicide itself, not the seed trait. The herbicide is actually regulated by EPA. Some concern was raised that expanding the use of 2, 4-D would speed up the development of weed resistance to the herbicide.
When commercialized, the Enlist Weed Control System will use Enlist Duo herbicide — a proprietary blend of glyphosate and 2,4-D choline. Dow AgroSciences will recommend a program approach to weed management that includes Enlist Duo and a residual herbicide in soybeans.
APHIS has concluded in its preliminary studies that the Enlist corn and soybean varieties are unlikely to pose plant pest risks. Thus, APHIS has preliminarily concluded that the best alternative would be to go ahead and deregulate the Enlist corn and the two soybean varieties. APHIS stated in the report this is the preferred option because neither the corn nor the soybean seeds are considered to be a plant pest.
APHIS added that deregulating the Enlist seeds likely will cause farmers to change management practices. Thus, 2, 4-D would become a more popular herbicide.
