N.S. researchers study drones for pesticide spraying, but Ottawa strict on regulation

A surveyor drone is shown at the Dalhousie University agricultural campus in Truro, N.S. on Dec. 17, 2025. THE CANADIAN PRESS/Emily Baron Cadloff

HALIFAX — As a drone glided across farmland on a December day in Truro, N.S., its robotic voice called out, “enable spraying.” Two nozzles on the bottom of the drone opened and released a vortex of liquid — just water that day, but other times it’s coloured dyes.

Dalhousie University student Chloe Toombs hopes one day that liquid will be a pesticide.

Toombs, a master’s candidate in the faculty of agriculture, is researching how plants absorb liquid released overhead by a drone. It’s still early, but results suggest drones could be just as effective as traditional equipment in applying chemicals to farmers’ fields.

That’s good news for farmers, Toombs says, because drones are much less destructive to some plant life compared to sprayers that drive on land; using the flying machines to spray fertilizer, she adds, could also potentially help cut costs. The bad news, however, is that the use of drones for agriculture in Canada — particularly for spraying pesticides — is tightly regulated and restricted.

Toombs and the rest of her research team at Dalhousie hope their findings will influence the federal government to loosen some of its rules and help make farming more efficient and less costly.

Toombs’s research involves wild blueberries, a staple crop in Nova Scotia that tends to populate in forested areas or abandoned farmland — and very sensitive to soil conditions. Using a traditional sprayer on a wild blueberry crop is difficult, Toombs says, because the sprayer repeatedly drives over tracks in the soil, compressing the ground and damaging the plant’s ability to grow.

“In a blueberry field, you’re driving through your crop. And you’re doing this multiple times per season.”

Using a drone could help. “Based on preliminary results from a study I’m doing, you’re losing pretty near all of your yield (under the sprayer) tracks. If you move the application to aerial, you’re going to keep that yield,” Toombs said.

Using a drone to spray fertilizers could also help reduce costs. Statistics Canada says the price of fertilizer jumped 80 per cent from 2021 to 2022. Prices stabilized somewhat in 2024, but started rising again in 2025 after tariffs from the U.S. caused the agriculture market to buckle.

Instead of covering an entire field with fertilizer, a farmer could use a drone to determine the specific areas that need to be fertilized, and apply the chemical as a spot treatment, says Hammad Farooq, Dalhousie PhD student in Environmental Sciences.

It’s not a practice that has been widely adopted in Canada yet, but Farooq says his initial test results are promising.

“We did four fields recently, and saved around 50 to 60 per cent in fertilizer, as compared to the uniform application,” Farooq said.

But for now, the techniques are stuck at the research level because of federal regulation, particularly regarding pesticides. Health Canada says any pesticides used by drones must be labelled for “remotely piloted aircraft systems.” Additionally, most drone operators need to be certified through Transport Canada and also receive any required provincial or territorial certifications.

In an email, officials from Health Canada said the agency “requires scientific evidence to demonstrate support that spraying pesticides through drones does not pose unacceptable risks to individuals and the environment.”

That’s part of why Toombs is logging so much data. She’s studying whether liquids sprayed from a drone travel beyond the field, further than when they are sprayed from a traditional land-based machine, or have other adverse effects.

The issue, Dalhousie researchers say, is the vast majority of pesticides don’t explicitly say “remotely piloted aircraft” on their label — only that they can be used for aerial application.

Other countries have varying levels of drone legislation in agriculture. In the U.S., the regulations are slightly more relaxed, says Travis Esau, director of the Atlantic Institute for Digital Agriculture at Dalhousie. “In most states, as long as it says on the pesticide label that it’s approved for aerial application, (that pesticide) is grandfathered in for drone use.”

Esau says traditionally, aerial application involved a helicopter or fixed-wing aircraft used in old-school crop dusting. In Canada, unless the pesticide companies specifically say the chemical can be applied with a drone, it’s not allowed.

Health Canada says only seven products on the market in Canada are properly labelled to support drone application so far. However, some of them are only approved for industrial use, meaning on areas without food crops. But they are not widely available for commercial agriculture.

Though Health Canada stated in an email that the agency has consulted with counterparts in the U.S. and Australia on drone regulations, ultimately, “regulatory decisions in Canada are made independently and within Canada’s own legislative and regulatory framework.”

Farooq is also using drones to create detailed prescription maps, which look almost like heat sensor images. The drone inputs images as it flies, allowing farmers to build real-time maps of their fields and know exactly which areas need more attention.

“Our end goal is not to replace farmers’ knowledge, but to support them better,” Farooq said. “If we are using the same traditional methods (to farm) we will not compete in the world.”

Emily Baron Cadloff, The Canadian Press