A number of prairie farmers are stocking up on chlorpyrifos in preparation for a 2023 ban of the insecticide.
The growers are buying chlorpyrifos (Lorsban) while they can because in December 2022 retailers must stop selling the insecticide in Canada. Health Canada announced a phase-out of the chemical in December 2020.
“(Farmers) have been reaching out to us, they (want) to pre-book the generic version of chlorpyrifos,” said Deepak Chaunkaria, sales agronomist with Johnston’s Grain — a grain brokerage and crop inputs supplier in Calgary.
“Guys are assessing their demand for the next couple of crop years. After that, they can’t use it.”
Chlorpyrifos has been around for more than 50 years and is still effective on a wide range of crop pests, including grasshoppers, cutworms, wheat midge and others, Chaunkaria said.
Hundreds of farmers possibly used it this summer to control a plague of grasshoppers on the Prairies.
“This year (there) was a huge grasshopper outbreak in southern Saskatchewan — south of Regina all the way to the southwestern part of the province,” Chaunkaria said.
Parts of Alberta also had grasshopper infestations.
Chlorpyrifos may be effective, but it is also controversial. For years, environmental groups have called for its ban, saying it’s a threat to human health, birds, mammals and beneficial insects.
Health Canada’s Pest Management Regulatory Agency announced its ban in 2020. A couple of weeks ago, in August, the United States Environmental Protection Agency revoked all “tolerances” for the chemical, which effectively prohibits its use.
“Today EPA is taking an overdue step to protect public health. Ending the use of chlorpyrifos on food will help to ensure children, farmworkers, and all people are protected from the potentially dangerous consequences of this pesticide,” said EPA administrator Michael S. Regan.
The EPA added that chlorpyrifos has been found to inhibit an enzyme, which leads to neurotoxicity, and has also been associated with potential neurological effects in children.
In its decision on chlorpyrifos, Health Canada’s Pest Management Regulatory Agency said the insecticide is an environmental hazard because it creates unacceptable risks for spiders, birds and mammals.
The American Farm Bureau Federation, one of the largest producer groups in the U.S., said the EPA decision was not based on science and “takes away an important tool to manage insects and pests.”
The president of the Michigan Farm Bureau, Carl Bednarski, had harsher comments about the EPA’s ban.
“The safety of this chemistry stands on over 50 years of experienced use, health and safety of workers and applicators, and over 4,000 studies that prove scientifically, the safety of this product to human health, and environmental impact,” he told Michigan Farm News. “The decision by the EPA robs Michigan’s growers of their due process and rights.”
In Canada, some growers are frustrated that Health Canada is banning chlorpyrifos, but farm groups have been relatively quiet about the issue.
In August 2019, Alberta Wheat, Alberta Barley, Alberta Pulse Growers and Alberta Canola sent a letter to Health Canada, reminding the PMRA why chlorpyrifos is an important tool for growers.
“In wheat and barley Lorsban is the only option for controlling both eggs and adults in wheat midge as any alternatives only control adult populations…. In canola, Lorsban is used when necessary to control outbreaks of bertha army worms, cutworms, diamond back moth larvae, grasshoppers, alfalfa looper and lygus bugs. In pulse crops chlorpyrifos is a consistent and effective pesticide for the control of grasshoppers in lentil crops.”
Farmers have other options for controlling grasshoppers and other pests, said John Gavloski, an entomologist with Manitoba Agriculture.
But removing chlorpyrifos from the market is a problem for wheat growers because it takes away one of only two insecticides registered for killing wheat midge.
“If you take chlorpyrifos off the market, that leaves you with just dimethoate…. That does create a shortfall (of options),” Gavloski said.
Wheat growers could opt for varieties with resistance to wheat midge, which offer some protection from the pest.
“I have a feeling there will be much more uptake of the midge-tolerant wheat varieties, once the chemical control options get thinner,” Gavloski said.
When chlorpyrifos is removed from the market at the end of 2023, insect control could become more costly for some growers.
A generic version of Lorsban likely costs around $6 to $8 per acre, Chaunkaria said.
He estimated the cost of replacement insecticides at $15 to $25 per acre.
That explains why western Canadian farmers are stocking up on chlorpyrifos, so they have sufficient supplies for the 2022 and 2023 growing seasons.
“This year, we have ordered containers and containers of this product, to satisfy the demand (from) our growers,” Chaunkaria said.
“Guys (farmers) have a real interest in this product and want to secure it.”