Health Canada’s April decisions on three neonicotinoid insecticides won’t change much for growers this year — but it also won’t be the last word on the subject.
Producers will still have access to most imidacloprid, clothianidin and thiamethoxam uses following the April 11 ruling.
In 2016, the federal government announced plans to phase out imidacloprid over three to five years, based on unacceptable risks to aquatic insects.
Proposed crackdowns on clothianidin and thiamethoxam, which Health Canada found posed a similar risk, quickly followed. Both pesticides were also slated to be phased out.
Health Canada later separated the debate between aquatic insect and pollinator risk.
The resulting stream of 2017 and 2018 proposals — based around pollinator risk — gave a more lenient tone.
Why it matters: Three neonicotinoid pesticides have final decisions from Health Canada, and both beekeepers and crop growers seem happy, but another round of decisions with heavier consequences is yet to come.
Health Canada proposed to cancel clothianidin for strawberry and orchard use and limit application on crops like melon and squash, but left other agricultural uses largely unchanged.
Thiamethoxam was slated for cancellation on foliar application in orchards and soil use for berries, melons, squash and fruiting vegetables — as well as a ban on foliar spray on berries, legumes and fruiting vegetables during bloom.
Imidacloprid, meanwhile, would be cancelled for some foliar applications (pome fruit, some tree nuts, most small berries and fruit) and soil uses (legumes, herbs, berries), but maintained its use for strawberries and potato, except during bloom. All three had added label requirements for cereal or legume seed treatments.
Those decisions largely echoed Health Canada’s final word on pollinator risk on April 11. The April decisions will have no impact on canola growers or seed treatment in potatoes, and foliar application in potatoes will still be allowed, although not while plants are in bloom. Thiamethoxam and imidacloprid, likewise, will still be allowed for seed treatment in soybeans and peas, although not for foliar treatment during bloom and thiamethoxam is limited to foliar use after soybeans are done blooming.
“Bloom is a little bit of a hazy term with potatoes,” Leonard Rossnagel, a retired potato agronomist and previous director with the Manitoba Seed Potato Growers Association, said, pointing to varietal differences in bloom.
Very few neonicotinoids are sprayed on a growing crop of potatoes anyway, he said.
Manitoba’s beekeepers say they’re happy canola growers skirted restrictions.
“One of our fears was that canola growers were not going to be planting as much canola,” Manitoba Beekeepers Association president Mark Friesen said. “That’s always a concern. This won’t be a hindrance to them.”
“Not to say that we don’t want to see less pesticides on a crop,” he added. “We always want to see less pesticides on a crop.”
The beekeeping association also praised new changes in application timing.
There’s little pollination impact between bees and potatoes, according to Friesen.
“That being said, potatoes are the No. 1 overspray risk for crops in Manitoba and other areas,” he said, although he noted that improved practices have limited bee loss on potatoes.
Growers aren’t celebrating just yet.
While final, Health Canada has said that the April 11 decisions are based only on risk to pollinators and are separate from risk to aquatic insects, one of the main concerns that prompted the proposed phase-out in 2016.
Decisions based on aquatic insect risk are expected in January 2020.
“These final decisions will not replace the pollinator decisions announced on April 11, 2019,” Health Canada said in an emailed statement. “If mitigation is required (e.g. cancellation of uses or restrictions to applications), it will be in addition to the cancellations and changes required to protect pollinators.”
Those 2020 decisions may yet curb most agricultural use of those chemicals. The department released proposed changes based on aquatic insect risk in August 2018. Those changes would cancel all outdoor crop use of thiamethoxam and clothianidin. Health Canada has said imidacloprid is also still up for cancellation for most agricultural uses, based on aquatic insect risk.
“Until that decision comes through, I don’t think the industry is breathing too much of a sigh of relief,” Rossnagel said. “We might call this one a hurdle.”
Impact so far
The debate over imidacloprid is unlikely to hobble the potato industry, Rossnagel said. The chemistry has become unpopular in potato use, although clothianidin and thiamethoxam are widely used as seed treatments.
Both are key in Colorado potato beetle control, something that has been of increasing concern in Manitoba, although producers have noted resistance issues with those chemistries.
Manitoba’s U-pick, fruit and vegetable farms may be harder hit by the April 11 decisions. Health Canada maintained its proposal to cancel foliar use in apple orchards for all three pesticides, as well as soil use for many berry crops and fruiting vegetables. The changes also cancelled foliar application of clothianidin in strawberries, and banned foliar use for many crops during bloom.
The decision will impact vegetable and fruit growers, the Canadian Horticultural Council says. It added that it will be working with growers during Health Canada’s two-year transition period.