The timing of the two factors was “coincidental and unfortunate,” Bayer said, underscoring that the cancellation of the project was part of a plan to save cash to pay for its expensive legal battles. At last count, the Leverkusen-based group was fighting 125,000 lawsuits alleging that its glyphosate-based weed killer Roundup acquired with Monsanto causes cancer.

In early June, a three-judge panel of the 9th US Circuit Court of Appeals in California ruled that the EPA had “substantially understated the risks related to the use of dicamba,” which is sprayed on soybeans and cotton crops that have been genetically engineered to resist the chemical. Farmers had sued over drift, which they claim damaged their crops.

The EPA only partly complied with the ruling, allowing existing stocks of the agrochemical made by Bayer, BASF and Corteva to continue to be sold for the current planting season, which ends officially on Jul. 31. Some state and local rules offer special opt-outs or mandate that use must be phased out sooner, however.

Meanwhile, the EPA has asked the appeals court to dismiss a motion filed by a group of farm and environmental organizations to hold it in contempt for partly overriding the initial decision. The agency’s argument is that vacating the registrations does not technically affect use of the now-unregistered herbicides.

Ending use of dicamba at the beginning of the in-season spray activity "would have draconian effects on the US agricultural system," the environmental watchdog, whose mission has been recalibrated under the administration of US president Donald Trump, asserted.

The plaintiffs had argued that the EPA's order to allow up to 16 million pounds of dicamba-containing herbicides to be sprayed over the top of cotton and soybeans through Jul. 31 “could cause widespread off-target injury again,” a phenomenon they noted was instrumental in the judges' decision to vacate the registrations.

Both Bayer and BASF have filed motions with the appeals court defending the EPA against the emergency motion that would halt use of dicamba immediately.

Lending the herbicide manufacturers a helping hand, reports said, are seven US commodity and agriculture trade groups that have filed "friend of the court" petitions defending the EPA’s decision.

Groups listed by the Reuters news agency include CropLife America and a coalition of US growers’ groupings, among them the Corn Growers Association, the National Association of Wheat Growers, American Farm Bureau and the National Sorghum Producers group.

US and Brazil slam Thai crop protectant ban

Separately, Reuters reported that the US and Brazil have lodged separate protests with Thailand over its ban on paraquat and chlorpyrifos earlier this month, saying the “restrictive” and “serious” move could hurt key agricultural exports.

Thailand added the herbicide and insecticide to its list of “most hazardous substances” on Jun. 1, citing a need to protect human health. The move triggered another health regulation banning imported food products containing residues of prohibited chemicals.

The ban could hit US and Brazilian exports of wheat and soy worth more than $1 billion annually year, according to United Nations data cited by the news agency.